CN109428544A - The switching method that photovoltaic module is accessed or removed is realized in battery strings group - Google Patents

Abstract

The present invention relates to the switching method that photovoltaic module is accessed or removed is realized in battery strings group, battery strings group includes the multiple photovoltaic modulies being connected in series, each photovoltaic module, which is each equipped with, switchs the removal that the access that photovoltaic module is coupled in battery strings group switchs and shields photovoltaic module from battery strings group.Transient state is shorted the tandem voltage of the offer of battery strings group belonging to one or many to be switched photovoltaic modulies, whether the processor detecting battery strings group of to be switched photovoltaic module configuration, which occurs transient state, is shorted event, by the transient state that detects be shorted event as judge from battery strings group will photovoltaic module access or removal foundation, can control assembly switch between the removal mode of the operating mode or shielding that normally access.

Description

The switching method that photovoltaic module is accessed or removed is realized in battery strings group

Technical field

Present invention relates generally to field of photovoltaic power generation, specifically, are related in the applied field containing photovoltaic cellThe switching module turned on and off in conjunction using controllable photovoltaic module, can determine that switching module is being connected according to the actual situationSwitch between the normal access operating mode of component or the removal mode for shielding photovoltaic module etc..

Background technique

Individual photovoltaic module output is often not enough to provide actual power demand, it is therefore necessary to the structure in a manner of series and parallelMeet design requirement at photovoltaic module array.When choosing photovoltaic module forming array, it will usually encounter due to series-parallelThe electrical parameter of various components is inconsistent or string group occurs part or the factors such as intermittent masking or aging and causes series-parallelOutput power afterwards is less than the case where the sum of single component output power, and technical term is referred to as mismatch loss, with photovoltaic electricIt stands the increase of the operation time limit, it is by the different degrees of actual power generation that must influence entire power station.Traditional centralized photovoltaic power generationSystem due to by surrounding building, cloud position, adjacent barrier the unpredictable factors such as size, will lead to photovoltaic groupThe power of part array causes incalculable damage.Therefore, recent domestic scholar is directed to the light that above-mentioned local shades generateThe research and probe that the problem of photovoltaic array power multimodal has carried out a variety of global maximum power points achieves some significant achievements, but stillIt can not so make all photovoltaic module work at respective maximum power point, not solve thoroughly because of local shades occlusion issue bandThe loss of the overall power for the string group come.For concentrating photovoltaic generating system, since only one energy conversion link is from direct currentVoltage to direct current is converted, and when control should consider to track solar panel maximum power point, guarantees the width of power grid output voltage againIt is worth phase and sine degree, controls complex inverter multichannel input and use the same MPPT, cannot identify series-parallel branch lightThe difference for lying prostrate component, will be greatly reduced generating efficiency, therefore discreteness or solar radiation condition for photovoltaic module parameterDifference caused by energy loss be helpless.Meanwhile if electric current mismatches when being connected in series, array work will causeWhen under a certain state, individual photovoltaic modulies are in reverse bias and form hot spot in array, if voltage is not in parallel connectionMatch, when will cause assembly array work under a certain state, forming circulation hot spot and circulation in array can all make to couple in series and parallelIn individual elements be in the state of consumption power, and assembly life-span may be damaged, especially when photovoltaic module array can not workUnder uniform illumination, the mismatch loss of generation is just bigger, and component can will be worked by the connection of by-pass diode in terminal boxAbnormal battery strings bypass, part reduces the electric current between battery or component and mismatches bring power loss, but can not eliminateBecause of current matching problem brought by the battery component of any one block of low current in battery strings group.

The power generation of power optimization device is promoted and the actual conditions in power station have much relations, is such as hidden in flat ground clearThe large-scale power station of gear and the promotion ratio of both photovoltaic power stations are different, the photovoltaic plant just to have put into operation and grid-connected fortuneIt is also different that row, which has the promotion ratio of the power station installation power optimizer of certain year, it is therefore necessary to pass through actual fieldScape is tested, and accumulation data carry out string group analysis, can provide beneficial reference for the optimization in power station operation.Increase optimizerAnnual photovoltaic power output gain afterwards, the ratio promoted under different irradiation are different.Since the photovoltaic module in array is specialProperty is inconsistent to be easy to cause current mismatch problem, and the whole generating efficiency of system is caused to decline to a great extent.Industry to solve this problemThe array architecture of distributed photovoltaic power optimization device is proposed, inside to solve the problems, such as that the current mismatch of photovoltaic array series component mentionsNew approach is supplied.Power optimization device can directly be integrated into matched complete electric power when battery component dispatches from the factory with battery componentEquipment, power optimization device can also be individually separately on being installed to battery component.For industry, newly-built photovoltaic plant is adoptedCost is saved with the project plan comparison that power optimizer and battery component integrate, the upgrading for already existing old photovoltaic plantTransformation then needs extraly to install additional power optimization device up in original component.Secure operating mode or maximum power pointTracking mode or suspend mode are problems in need of consideration, either overhaul situations such as still powering on or install for the first time, requireSwitching is between normal mode of operation and safe mode with the safety of safeguard work personnel or owner.

Summary of the invention

In an optional non-limiting embodiment, this application discloses a kind of power optimizations for photovoltaic moduleThe method that device switches between different working modes, it is characterised in that any one battery strings group includes the multiple of series connectionPhotovoltaic module, each photovoltaic module are each equipped with the power optimization device for executing maximum power point tracking, each batteryRespectively corresponding power optimization device is connected in series and constitutes a link to provide tandem voltage each photovoltaic module in string group；

The method includes: that transient state is shorted link belonging to the power optimization device of any one to be switched operating mode and is providedTandem voltage；Whether detecting link, which occurs transient state, is shorted event, and the power optimization device of the to be switched operating mode is being detectdIt measures when transient state is shorted event and is switched to another operating mode from a kind of operating mode.

Above-mentioned method, it is characterised in that: transient state is shorted belonging to the power optimization device of any one to be switched operating modeLink provided by tandem voltage；Detecting by link that transient state is shorted because of the predetermined finger that tandem voltage is short-circuited and is inducedTarget variable quantity；When the variable quantity meets preset change condition, the power optimization device of to be switched operating mode is from one kindOperating mode is switched to another operating mode.

Above-mentioned method, it is characterised in that: the desired indicator includes at least the transient state for flowing through the link being shorted by transient stateShort circuit current and/or include by transient state be shorted link tandem voltage transient changing rate.

Above-mentioned method, it is characterised in that: the operating mode of power optimization device includes at least: the output electricity of power optimization devicePressure is consistently less than the safe mode of input voltage；Power optimization device makes the photovoltaic module matched with it work in maximum power pointPowerinjected method mode.

Above-mentioned method, it is characterised in that: the safe mode of power optimization device includes at least: make the output of power optimization deviceVoltage and input voltage ratio are clamped down on lower than a preset ratio relationship.

Above-mentioned method, it is characterised in that: the power optimization device as switched-mode power supply exports paired photovoltaicComponent implements the output voltage after DC voltage conversion；The power optimization device of to be switched operating mode switches from a kind of operating modeMode to another operating mode includes: to change the switch operation of the pulse width modulating signal for driving power optimizerFrequency or duty ratio, the switching operating frequency or duty ratio of the pulse width modulating signal under two kinds of different working modes are different.

Above-mentioned method, it is characterised in that: in link tandem voltage be short-circuited and the desired indicator that induces further include: tandemThe statistics number that voltage is short-circuited in preset period of time meets anticipated number.

Above-mentioned method, it is characterised in that: each power optimization device includes being coupled to a photovoltaic module positive and negative anodesFirst, second input terminal and including providing the first, second output end of output voltage, output capacitance is connected to first, secondBetween output end；In the link that multiple power levels optimizer is connected in series, the second output terminal of previous stage power optimization device is coupled toFirst output end of neighboring later stage voltage conversion circuit；The respective output capacitance of multiple power levels optimizer is connected in series with each other,The tandem voltage that link provides is equal to the superposition value of the voltage in it in the respective output capacitance of multiple power levels optimizer.

Above-mentioned method, it is characterised in that: the first first order power in link in concatenated multiple power levels optimizer is excellentChange and is coupled with control switch between the first output end of device and the second output terminal of the afterbody power optimization device at end；Transient stateIt is shorted the mode for the tandem voltage that link provides are as follows: disconnect after connecting control switch or disconnect rapidly, do not allow to be continuously turned on.

Above-mentioned method, it is characterised in that: transient state is connected rapid again after the one instruction time of control switch when being shorted linkDisconnect control switch；Meet preset change condition in the variable quantity for detecting desired indicator and meets preset change conditionWhen duration is identical as the instruction time, the power optimization device of to be switched operating mode just executes the switching of operating mode.

In an optional non-limiting embodiment, this application discloses a kind of power optimizations for photovoltaic moduleThe method that device switches between different working modes, wherein battery strings group includes the multiple photovoltaic modulies being connected in series；EachPhotovoltaic module is each equipped with the power optimization device for executing maximum power point tracking；Each photovoltaic group in each battery strings groupThe corresponding power optimization device of part, which is connected in series, constitutes a link to provide tandem voltage；

The method includes: that transient state is shorted the offer of link belonging to the power optimization device of one or many to be switched operating modesTandem voltage；It is shorted event by whether the power optimization device detecting link of to be switched operating mode occurs transient state, by detectingTo transient state be shorted event as the foundation for being switched to another operating mode from a kind of operating mode.

Above-mentioned method, it is characterised in that: detecting transient state be shorted event mode include detecting tandem voltage be short-circuited andThe variable quantity of the desired indicator of induction；When the variable quantity meets preset change condition, the power of to be switched operating modeOptimizer is just switched to another operating mode from a kind of operating mode.

Above-mentioned method, it is characterised in that: the desired indicator includes at least the wink for flowing through the link being shorted by transient stateState short circuit current and/or include by transient state be shorted link tandem voltage transient changing rate.

Above-mentioned method, it is characterised in that: the operating mode of power optimization device includes at least: the output electricity of power optimization devicePressure is consistently less than the safe mode of input voltage；And power optimization device makes the photovoltaic module matched with it work in maximum powerThe powerinjected method mode of point.

Above-mentioned method, it is characterised in that: the safe mode of power optimization device includes: to make the output of power optimization deviceVoltage and input voltage ratio are clamped down on lower than a preset ratio relationship.

Above-mentioned method, it is characterised in that: the power optimization device by being used as switched-mode power supply exports paired lightIt lies prostrate component and implements the output voltage after DC voltage conversion；The power optimization device of to be switched operating mode implements different working modesThe mode of switching includes: to change for driving the switching operating frequency of the pulse width modulating signal of the power optimization device or accounting forEmpty ratio, so that the switching operating frequency of the pulse width modulating signal under two kinds of different working modes or duty ratio are different.

Above-mentioned method, it is characterised in that: it further includes limiting that detecting transient state, which is shorted event: tandem voltage is in preset period of timeThe statistics number being short-circuited meets anticipated number.

Above-mentioned method, it is characterised in that: each power optimization device includes being coupled to a photovoltaic module positive and negative anodesFirst, second input terminal and including providing the first, second output end of output voltage, output capacitance is connected to first, secondBetween output end；In the link that multiple power levels optimizer is connected in series, the second output terminal of previous stage power optimization device is coupled toFirst output end of neighboring later stage voltage conversion circuit；The respective output capacitance of multiple power levels optimizer is connected in series with each other,Total tandem voltage that link provides is equal to the superposition value of the voltage in it in the respective output capacitance of multiple power levels optimizer.

Above-mentioned method, it is characterised in that: the first first order power in link in concatenated multiple power levels optimizer is excellentChange and is coupled with control switch between the first output end of device and the second output terminal of the afterbody power optimization device at end；To chainThe tandem voltage that road provides implements the mode that transient state is shorted are as follows: disconnects rapidly after connecting the control switch.

Above-mentioned method, it is characterised in that: detecting transient state be shorted event mode include detecting tandem voltage be short-circuited andThe variable quantity of the desired indicator of induction；And it connects and disconnects control switch after the one instruction time of the control switch rapidly again；FromAnd the variable quantity for detecting desired indicator meet preset change condition and transient state be shorted event duration with it is describedWhen indicating that the time is identical, the power optimization device of to be switched operating mode just executes the switching of operating mode.

In an optional non-limiting embodiment, this application discloses one kind to be realized in battery strings group by photovoltaicSwitching method component access or removed, in which: battery strings group includes the multiple photovoltaic modulies being connected in series；Each photovoltaic groupPart is each equipped with the switch of the access for coupling photovoltaic module in battery strings group and is used for photovoltaic module from battery stringsThe removal switch shielded in group；

The method includes: the tandem that transient state is shorted the offer of battery strings group belonging to one or many to be switched photovoltaic moduliesVoltage；Whether the processor detecting battery strings group of to be switched photovoltaic module configuration, which occurs transient state, is shorted event, by detectingTransient state be shorted event as judge from battery strings group will photovoltaic module access or removal foundation.

Above-mentioned method, it is characterised in that: detecting transient state be shorted event mode include detecting tandem voltage be short-circuited andThe variable quantity of the desired indicator of induction；When the variable quantity meets preset change condition, to be switched photovoltaic module just fromAccess or remove one of pattern switching to another kind mode.

Above-mentioned method, it is characterised in that: the desired indicator, which includes at least to flow through, is shorted induced wink by transient stateState short circuit current and/or include be shorted by transient state caused by tandem voltage transient changing rate.

Above-mentioned method, it is characterised in that: it further includes limiting that detecting transient state, which is shorted event: tandem voltage is in preset period of timeThe statistics number being short-circuited meets anticipated number.

Above-mentioned method, it is characterised in that: realize the switching that each photovoltaic module is accessed or removed from battery strings groupModule includes: the first, second input terminal and the first, second output end；First, second input terminal is corresponding to be respectively coupled to corresponding lightLie prostrate the positive and negative anodes of component；Access switch is coupled between first input end and the first output end or the second input terminal and second exportsBetween end；Switch is removed to be coupled between the first output end and second output terminal；When multistage switching module is connected in series, before anyThe second output terminal of level-one switching module is coupled to the first output end of neighboring later stage switching module；To multistage switching moduleThe total tandem voltage provided is equal to the first output end of first first order switching module and cutting for end afterbody in itChange the mold the superposition value of the voltage between the second output terminal of block.

Above-mentioned method, it is characterised in that: whole photovoltaic modulies in battery strings group are given by respective removal switchBypass be shorted when or at least part photovoltaic module by respective removals switch bypassed be shorted when, photovoltaic module fromRemove pattern switching arrive access module mode are as follows: in battery strings group generation potential difference and into battery strings group Injection Current,Access module is restored to when the processor of photovoltaic module configuration senses Injection Current.

Above-mentioned method, it is characterised in that: any one switching module is in its first output end and previous stage switching moduleSecond output terminal between be coupled with current divider for sensing Injection Current；Or any one switching module is second defeated at itThe current divider for sensing Injection Current is coupled between outlet and the first output end of rear stage switching module.

Above-mentioned method, it is characterised in that: any one photovoltaic module is equipped with a storage capacitor as the processing of its configurationDevice power supply is charged from the anode of photovoltaic module by the diode of one-way transmission to storage capacitor.

Above-mentioned method, it is characterised in that: first of the first first order switching module in concatenated multistage switching moduleControl switch is coupled between the second output terminal of the afterbody switching module at output end and end；Battery strings group is providedTandem voltage implements the mode that transient state is shorted are as follows: disconnects rapidly after connecting the control switch.

Above-mentioned method, it is characterised in that: detecting transient state be shorted event mode include detecting tandem voltage be short-circuited andThe variable quantity of the desired indicator of induction；And it connects and disconnects control switch after the one instruction time of the control switch rapidly again；FromAnd the variable quantity for detecting desired indicator meet preset change condition and transient state be shorted event duration with it is describedWhen indicating that the time is identical, the switching of to be switched photovoltaic module ability execution pattern.

Detailed description of the invention

To keep above-mentioned purpose and feature and advantage more obvious and easy to understand, specific embodiment is done with reference to the accompanying drawingDetailed explaination, read it is described further below and referring to the following drawings after, feature and advantage of the invention will be evident.

Fig. 1 is that photovoltaic module is first connected into battery strings then by battery in series and parallel to the schematic diagram of inverter power supply.

Fig. 2 is the example schematic that multiple photovoltaic modulies are connected in series with each other in the same battery strings group.

Fig. 3 is the corresponding example schematic that power optimization is carried out by a voltage conversion circuit of a photovoltaic module.

Fig. 4 is the schematic diagram that the link with multilevel voltage conversion circuit is executed once or repeatedly short circuit connects.

Fig. 5 is that the link with multiple power levels optimizer is short-circuited the schematic diagram for generating short circuit current in the loop.

Fig. 6 is the logical schematic that the power optimization device of to be switched operating mode switches between different working modes.

Fig. 7 is that photovoltaic module utilizes the concatenated schematic diagram of switching module that access or removal photovoltaic module can be achieved.

Fig. 8 is the corresponding example schematic for being accessed or being removed by a switching module of a photovoltaic module.

Fig. 9 is the schematic diagram that the link with multistage switching module was short-circuited and generated in the loop short circuit current.

Specific embodiment

Below in conjunction with each embodiment, clear and complete elaboration is carried out to the solution of the present invention, described embodiment is onlyIt is the present invention with the embodiment used in illustrating is described herein and not all embodiment, based on the embodiments such as this, the technology of this fieldScheme obtained belongs to protection scope of the present invention to personnel without making creative work.

In switch power supply system, power supply is usually to use power semiconductor as switch element, passes through periodicityOn-off switch, the duty ratio of control switch element adjust output voltage.Switching Power Supply mainly by input circuit, translation circuit withAnd the composition such as output circuit and control unit.Power conversion is its core, is mainly made of switching circuit, and certain occasions are alsoIt has been applied to transformer.In order to meet high power density requirement, converter needs work in high frequency state, and switching transistor will adoptWith the crystal arm that switching speed is high, the turn-on and turn-off time is short, typical power switch has power scr, power field effect brilliantBody pipe and insulated type bipolar junction transistor etc. are a variety of.It is mixed that control mode is divided into pulse width modulation, pulsewidth modulation and frequency modulation(PFM)It is a variety of to close modulation, pulse frequency modulated etc., commonly uses pulse width modulation mode.Switched-mode power supply SMPS is according to outputting and inputting voltageThe difference of form is divided into AC to AC (AC/AC) converter such as frequency converter, transformer；It is also divided into AC-to DC (AC/DC)Converter such as rectifier；And it is divided into direct current to exchange (DC/AC) converter such as inverter etc.；Be divided into DC to DC(DC/DC) converter such as voltage changer, power pack.The switched-mode power supply being applied in the application is mainly direct currentTo the electric pressure converter of direct current.The switching noise generated caused by switch operation when Operation switch mode power can makeElectromagnetic interference is generated in the electronic equipment for including switched-mode power supply.Switching noise is indicated due to configuration switched-mode power supplyThe switching operating frequency of power switch and the noise component(s) occurred and certain harmonic components.When electromagnetic interference occurs, includingThe operation of the periphery electronic device of the electric device of switched-mode power supply is interfered.It is usual for inhibiting electromagnetic interference to occurMethod is to change the method for modulation switch operating frequency.But warbled method can be generated and be modulated according to switching operating frequencyOutput voltage ripple, which is added on the output voltage ripple component as caused by the ripple of input voltage,To generate bigger output voltage ripple.

In switch power supply system, the application makes full use of the voltage changer for being considered as the DC to DC of power optimization deviceThe characteristic of this Switching Power Supply itself is produced voltage conversion circuit by the way that inductive/capacitive element is added in voltage conversion circuitRaw switch operation institute's output voltage is coupled to the input terminal or output end of circuit itself, is further transferred to total for providingOn the public direct-current transmission line of tandem voltage.

Power optimization device is the buck-boost type voltage changer and a unimodule rank of a DC to DCBattery maximum power tracing power equipment.After power optimization device carries out maximum power optimization to unimodule, it is transferred to terminal inversionAfter device carries out direct current to the processing of alternating current, the local online that uses or generate electricity is supplied.Terminal inverter usually can be no maximumThe pure contravariant equipment of powerinjected method or contravariant equipment equipped with second level maximum power tracing.The power optimization device of mainstream is broadly divided intoSeries FPB and parallel FPB, topology are also slightly distinguished, for example BUCK or BOOST or BUCK-BOOST circuit.

The power optimization device of tandem type using fixed voltage design concept.In simple terms, inverter control plate rootThe voltage that a stable DC bus is determined according to exchange end voltage summarizes the maximum power that each concatenated optimizer is collected, intoAnd calculate bus current and by wirelessly or electrically power carrier-wave transmission to optimizer.The voltage etc. of each optimizer output end at this timeIn collected component maximum power power divided by bus current.After when component is blocked the case where, the optimizer meetingRedefine peak power output value according to volt-ampere curve, by by wirelessly or electrically power carrier-wave transmission to inverter control plate.?Under the premise of maintaining DC bus-bar voltage constant, control panel recalculates bus current (becoming smaller) and feeds back to each optimizer.ThisWhen the power of component that is blocked reduce, which can also be depressured to confirm that output electric current is up to standard.Other groups not being blockedThe optimizer of part, which can then boost, carrys out output electric current up to standard.If component is blocked excessively serious, power optimization device will be bypassedFall the component of the serious shielding until its be restored to can working condition, this adjusting is the process that a voltage is supplied in fact, fromAnd the DC terminal busbar voltage for being supplied to the most stable of inverter and optimizing.

The power optimization device of parallel connection type is equally using fixed voltage mode.Inverter is according to direct current and alternating currentClose ring determines busbar voltage, and each optimizer boosts to respective output end voltage specified numerical value, input at this time inverseBecome the summation that the electric current of device is equivalent to maximum power that each optimizer is collected into divided by electric current after specified voltage.Due to spissatusThe voltage influence of layer blocked for component is little, and the main electric current for influencing output, parallel optimizer is substantially not in frequencyNumerous voltage mispairing is adjusted, and due to being parallel relationship, the electric current of output will not affect one another again, so this can be regarded reallyMake advantage of the parallel optimizer compared to tandem.If individual elements can not be started boosting and be set by serious block simultaneouslyStandby, optimizer disconnects automatically and sends error signal, and restarts until occlusion issue removes.However compared to stringConnection topology, topology in parallel similarly have the defects that as Miniature inverter that boosting span is larger.Relatively more universal at presentComponent open-circuit voltage is about 38 volts, and operating voltage is about 30 volts, and voltage raising and reducing range is all control to series topology under normal circumstancesSystem is between 10%-30%, and in undertension, variation range is promoted between 10%-90%.However it is in parallel topological and miniature inverseBecome device to require a component input voltage and boost to quite high numerical value, about 400V or so, it is clear that this be equivalent to 10 times withOn promotion amplitude.This for not use transformer occasion, but only by switch control booster apparatus be one ratioThe more challenging duty cycle.

One maximum topological feature of power optimization device is exactly that component and inverter functionality are separated, this is different from traditionPhotovoltaic system.It seems component and inverter is accessed by optimizer, in fact component is used only to starts optimization device, and optimizerIt is cooperated after the maximum power of collection assembly and gives inverter function.Because the technology of fixed voltage not only solves photovoltaic hairThe problem of partial occlusion of electric system, for the system of multiple groups string, each group string component count does not need equal or even a string same yetEach component in group is the same towards also not needing.For tandem type optimizer, the open-circuit voltage after open circuit is only as 1VSmall voltage, for parallel connection type optimizer, open-circuit voltage after the open circuit at most namely open-circuit voltage of component, so for hairThe security performance and reliability of electric system are also the progress of a great-leap-forward.

In addition to circuit topology is in the advantage of structure, power optimization device also has elder generation on maximum power point tracking algorithmIt advantage.The tracing algorithm of traditional maximum power point is substantially based on two kinds: climbing method and logic method of determining and calculating.Advanced pointBack tracking method these also use combined techniques: such as climbing method binding constant area method cooperates the full scan method of Fixed Time IntervalTo find maximum power point；Also have in conjunction with slope polarity method and conductance increment method, cooperation detects paces control methods to find maximumPower points.For these algorithms under ideal test condition, accuracy rate can reach 99% or more, and current maximum challenge in fact isMore wave crests and illumination increase situation suddenly.More wave crests mean to go out in the power-current or power vs. voltage curve figure of an arrayMultiple power peaks are showed.The reason of it is formed is varied, one of them is because members are because block and forward biasTurn bypass diode, causes the battery of one third to be bypassed and the operating voltage of string group is caused to reduce, and then array occurVoltage mispairing and there are more wave crest situations.Or it because blocks and bypass diode is still in the inactive shape of reverse deflectionState, and current mismatch occur in same group of string caused by more wave crest situations.More wave crests and illumination increase suddenly for many maximumsPower points algorithm has tremendous influence, since its is uncontrollable and variability, can obscure judgement of the tracker for detection directionIt and which peak value to be the judgement of maximum power point for.The basic reason of this problem in fact, the component exactly accessed are too many?.Just think and only connect a component if each optimizer, each component only has two to three bypass diodes, and inter-moduleIt is independent of each other, the analysis of maximum power point and tracking difficulty can be greatly reduced in this, simultaneously for the logic of controllerEditor is also very succinct and accurate.Because only one 38 volts and 8.9 peace IV curve graph, the maximum power of optimizerPoint tracking does not need to track maximum power point with traditional algorithm, it is current it is general there are two types of, be point of contact back tracking method first,The method that resistance control methods and voltage control method followed by equipped with second level tracking combine.It is based on this advantage, just may be usedTo allow optimizer to there is 30% or so production capacity to be promoted compared to traditional inverter.In addition different from the limited of Miniature inverterAC power, power optimization device can transmit the power being collected into inverter completely.

Power optimization device is not only compatible with all crystal silicon battery plates, can also be matched in the hull cell system of part,Industry is also making great efforts that optimizer is allowed to possess broader compatibility range.However most of Miniature inverter can not be compatible with or oneselfBody functional grounding causes it that can not match with the component of a part of mainstream currently on the market.Meanwhile the input of power optimization deviceVoltage range about between 5 volts to 50 volts, this assures even component in the case where serious cover, optimization circuit according toStarting state can so be kept and worked on.Power optimization device can be matched with third party's inverter, pass through additional controlBox carries out the communication with third party's inverter and the regulation to system.Power optimization device or voltage conversion circuit are substantially straightThe converter for flowing to direct current, such as BUCK, BOOST and BUCK-BOOST circuit.It must be, it is emphasized that being directed to photovoltaic electric in the prior artAny scheme of the maximum power tracing in pond is equally applicable to the voltage conversion circuit of the application, common maximum power tracing methodThere are constant voltage process, conductance increment method, perturbation observation method etc., how the application no longer executes maximum power to voltage conversion circuitThe scheme of tracking MPPT is repeated.

In field of photovoltaic power generation, photovoltaic module or photovoltaic cell PV are one of the core component to generate electricity, solar panelIt is divided into single crystal silicon solar cell, polycrystalline silicon solar cell, non-crystal silicon solar cell etc., large-scale collection in the direction of mainstream technologyThe substantial amounts for the battery component that Chinese style photovoltaic plant uses, the battery component that small-sized distributed residents small hydropower station usesQuantity it is relatively fewer.Since silion cell is generally up in the service life that this field requires more than 20 years service life, so rightThe chronicity and durability monitoring of solar panel are essential.Many inside and outside factors can all lead to the hair of photovoltaic moduleElectrical efficiency reduces, such as the manufacturing variation or installation difference or shadow occlusion or maximum power tracing adaptation between photovoltaic module itselfEtc. factors can all cause inefficiency.By taking typical shadow occlusion as an example, such as fruit part photovoltaic module by cloud or building orAfter the similar situations such as the shadow of the trees or dirt are blocked, this members will be become to load and no longer produce electricl energy, photovoltaic group by power supplyPart may be higher in the serious local local temperature of generation hot spot effect, and some is even more than 150 DEG C, leads to component regional areaThe permanent damages such as blackening, solder joint thawing, encapsulating material aging, glass rupture, corrosion are burnt or are formed, to the length of photovoltaic modulePhase safety and reliability causes hidden danger greatly.Photovoltaic plant/system urgent problem to be solved is exactly: can see in real timeExamine the working condition of each piece of mounted photovoltaic battery panel, can excess temperature to battery, over-voltage, overcurrent and output end be shorted etc.Abnormal conditions carry out early warning, and it is ten that this, which takes similar to active safety shutdown or other emergency measures the battery being abnormal,Divide significant.Either centralized photovoltaic plant or distributed small hydropower station, based on the work for photovoltaic module acquisitionThere are the component of potential problems is very necessary for judging and identifying those for supplemental characteristic.

In field of photovoltaic power generation, photovoltaic module or photovoltaic cell need first to be connected into battery strings group, and battery strings group is again simultaneouslyJoin to power equipment such as header box or inverter power supply, be related to the installation of component or battery, this needs absolute safety.Such asExcess temperature or the similar abnormal conditions such as over-voltage or overcurrent occur for fruit photovoltaic module, undoubtedly we need actively to go triggering shutdown theseThe movement of abnormal photovoltaic module, our needs when abnormal photovoltaic module exits abnormality and is restored to normal conditionThese photovoltaic modulies are accessed again, this also needs absolute safety.And some occasions need detection components generated energy orIt is monitoring output power situation that person, which says, this is the foundation of determination component quality, for example, if the lower power production of component is apparentIt is then likely to be also that power generation anomalous event has occurred, be blocked by birds droppings, dust, building, the shadow of the trees, cloud etc., this needs usIt removes cleaning battery or changes the measures such as installation position.It will be apparent to one skilled in the art that single crystal silicon solar cell, the polysilicon sunBattery, non-crystal silicon solar cell etc. are all the materials for belonging to characteristic and being easy to happen decaying, and the attenuation degree of monitor component is mustIt wants, this is of crucial importance for the quality for judging battery.Problem is: we in huge assembly array it is not apparent how screenIt is normal component that those components, which are abnormal component those components, and ensuing disclosure can solve the problems, such as this.Many times we are installingStage will directly judge the bad battery or component of those quality, and never allow to there are problems that quality flaw battery simultaneouslyIt assembles/is installed in photovoltaic battery array, otherwise enter photovoltaic battery array containing defective in quality battery and result in entirelyArray generator inefficiency, worse is that the abnormal voltage value of a certain piece or a few pieces problem battery or current value may causeEntire battery strings group is all damaged together, causes biggish loss.

Referring to Fig. 1, it is with the directly concatenated difference of traditional photovoltaic module: is that any photovoltaic module is equipped with firstPower optimization device, power optimization device complete battery and inverter between voltage matches and electrical isolation, then again by inverterThe inversion for completing direct current to alternating current is converted and gives terminal load supplying.It is similar with conventional scheme, photovoltaic generating system toolThere are concatenated multiple photovoltaic module PV1, PV2 ... PVN, they, which are concatenated, constitutes battery pack string, and battery strings group is connected in series by N gradesPhotovoltaic module PV1 to PVN concatenate constitute.Photovoltaic module or photovoltaic cell PV, which are each equipped with, executes maximum power tracing MPPTThe photovoltaic voltage that generates of power optimization circuit PO: first photovoltaic module PV1 in such as battery strings group by first powerOptimization circuit PO1 carries out the voltage conversion of DC to DC to execute power optimization, the photovoltaic that second photovoltaic module PV2 is generatedVoltage carries out voltage conversion by second power optimization circuit PO2, until the photovoltaic voltage that generates of N grades of photovoltaic module PVN byN grades of power optimization circuit PON carries out voltage and converts to execute power optimization function.Substantially, with every piece of photovoltaic cell PVThe voltage of corresponding power optimization circuit PO output can just characterize photovoltaic cell PV and provide the reality in photovoltaic cell string groupBorder voltage.It sets and is serially connected with first order photovoltaic module PV1, second level photovoltaic module in any a string of photovoltaic cell string groupThe photovoltaic module PVN of PV2 ... to N grades: first order power optimization circuit PO1 by the photovoltaic voltage of first order photovoltaic cell PV1Source executes maximum power tracing and carries out voltage conversion and export V₁, second level power optimization circuit PO2 output V₂, N grades of functionRate optimizes circuit PON and the voltage of N grade of photovoltaic cell PVN execution maximum power tracing is carried out to DC voltage conversion and defeatedV out_N。

Referring to Fig. 1, it can be calculated that tandem voltage total in any one string photovoltaic cell string group is roughly equal to: the first orderThe voltage V of power optimization circuit PO1 output₁In addition the voltage V of second level power optimization circuit PO2 output₂Again plus third level powerOptimize the voltage V of circuit PO3 output₃... until being added to the DC voltage V that N grades of power optimization circuit PON is exported_N,The operation result of tandem voltage is equal to V₁+ V₂+……V_N.Power optimization circuit/optimizer or voltage conversion circuit PO are upperThe topology hereinafter referred to is substantially the DC/DC converter of DC to DC, typical buck converter BUCK, boosting changeParallel operation BOOST, buck-boost converter BUCK-BOOST etc. are suitable for power optimization circuit.It must be stressed that the prior artAny scheme of the maximum power tracing for photovoltaic cell disclosed can equally be well applied to the voltage conversion circuit of the application, oftenThe maximum power tracing method seen has constant voltage process, conductance increment method, perturbation observation method etc., and the application no longer individually turns voltageThe scheme for changing circuit execution maximum power tracing is repeated.Power optimization circuit corresponding with every piece of photovoltaic cell is noted aboveThe voltage of output just characterizes the photovoltaic cell and provides the virtual voltage in photovoltaic cell string group: first order power optimization circuitPO1, power optimization circuit PON of power optimization circuit PO2 to N grades of the second level etc. are connected by concatenation transmission line LAN, shouldN is natural number, is conveyed to the electric power such as header box/inverter by DC bus again by the tandem voltage of optimizer superposition on transmission lineEquipment INVT carries out/inversion of converging.The bus electricity of pressure stabilizing is also in series between positive and negative anodes as the transmission line LAN of DC busHold CD.

Referring to fig. 2, in an alternate embodiment of the invention: the first input end of first order voltage conversion circuit PO1 is connected to pairingThe anode of photovoltaic cell PV1 and the second input terminal of first order voltage conversion circuit PO1 are connected to the negative electrode of photovoltaic cell PV1Place, voltage conversion circuit PO1 oneself the first output end or first node N1 and second output terminal or second node N2 itBetween export burning voltage, i.e. first order voltage conversion circuit PO1 captures photovoltaic electric between first input end and the second input terminalPond PV1 carries out power optimization by the voltage source that photovoltaic effect generates and provides output voltage.

Referring to fig. 2, in an alternative embodiment: the first input end of N grades of voltage conversion circuit PON is connected to the light of pairingThe second input terminal of volt battery PVN anode and N grades of voltage conversion circuit PON are connected at photovoltaic cell PVN negative electrode, NThe voltage conversion circuit PON of grade is between the first output end or first node N1 and second output terminal or second node N2 of oneselfBurning voltage is exported, N grades of voltage conversion circuit PON captures photovoltaic cell between first input end and the second input terminalPVN carries out power optimization by the voltage source that photovoltaic effect generates and provides output voltage.

Referring to fig. 2, in practical applications, the photovoltaic cell or photovoltaic module of many quantity are connected in series to constitute expectionBattery pack string, it is assumed that N grades of photovoltaic cell PV1, PV2 ... PVN series connection in total, which usually takes the natural number greater than 1, electricityThe tandem voltage of pond group string is roughly equal to: the voltage V of first order photovoltaic cell PV1 output₁In addition second level photovoltaic cell PV2 is defeatedVoltage V out₂Along with the voltage ... of third level photovoltaic cell PV3 output is until be added to N grades of photovoltaic cell PVN outputVoltage V_N, it is equal to V₁+ V₂+……V_N.The tandem voltage of battery pack string is sent to the power equipments such as header box or inverterINVT.N grades of photovoltaic cell PV1, PV2 ... PVN series connection, wherein photovoltaic cell series connection lead to the total voltage provided very in totalHeight, the voltage of extremely dangerous or actual measurement individual individual components is very for service personnel or installation personnelIt is low, but being together in series is exactly high pressure etc..

Referring to fig. 2, every piece of photovoltaic module or photovoltaic cell, which are respectively each equipped with, executes boost or depressurization or buckVoltage conversion circuit: the photovoltaic voltage that for example first photovoltaic module PV1 in a battery strings group is generated is by first voltageConversion circuit PO1 carries out the conversion of DC/DC voltage to execute voltage up-down, the photovoltaic voltage that second photovoltaic module PV2 is generated bySecond voltage conversion circuit PO2 carry out voltage conversion ... ... until N grade of photovoltaic module PON generation photovoltaic voltage byN step voltage conversion circuit PON carries out voltage conversion to execute voltage up-down function.It is in fact corresponding with every piece of photovoltaic cell PVThe voltage of voltage conversion circuit PO output can just characterize photovoltaic cell PV and provide the virtual voltage in photovoltaic cell string group.Voltage conversion circuit PO or voltage changer are substantially the electric pressure converter topologys of DC to DC.The processing introduced hereinData of the device 200 in addition to acquiring photovoltaic module, go back output switch control signal for driving voltage converter: in electric pressure converterPower switch turns on and off switch control signal or the modulated signal that state is substantially exported by microprocessor 200 to controlSystem, such as logical device, processor, control device, state machine or the controller of plural number or chip, software-driven control, gate arrayColumn and/or other equivalent controllers, wherein especially typical using pulse-width signal as switch control signal.Processor outputSwitch control signal driving switch power-supply system in power switch turned on and off between operation, Switching Power Supply systemSystem is usually to pass through periodical on-off switch, the duty of control switch element as switch element using power semiconductorThan adjusting output voltage.

Referring to fig. 2, first order voltage conversion circuit PO1 shown in figure, second level voltage conversion circuit PO2 are until so-calledN grades of voltage conversion circuit PON etc. be connected in series by concatenation line LAN, multilevel voltage conversion circuit or power optimizationIn the link that device PO1-PON is connected in series, connection relationship: the second output terminal of any previous stage power optimization device is coupled to adjacentFirst output end of rear stage voltage conversion circuit, so that the respective output capacitance of multiple power levels optimizer PO1-PON is mutually gone here and thereConnection connection, total tandem voltage that link provides are equal to the voltage in it in the respective output capacitance of multiple power levels optimizerSuperposition value.The second output terminal N2 of first order voltage conversion circuit PO1 is coupled to the of neighboring later stage voltage conversion circuit PO2One output end N1, the second output terminal N2 of second level voltage conversion circuit PO2 are coupled to neighboring later stage voltage conversion circuit PO3The first output end N1, and so on, the second output terminal N2 of N-1 grades of voltage conversion circuit be coupled to neighboring later stage electricityThe first output end N1 of voltage conversion circuit PON.The output capacitance CO of each power optimization device is connected to its first and secondBetween output end N1-N2, total tandem voltage that link provides is equal to multiple power levels optimizer PO1-PON in it and respectively exportsThe superposition value of the voltage of CO on capacitor, to transmit the voltage institute respectively exported on concatenation line by voltage conversion circuit PO1-PONIt is superimposed obtained tandem voltage and is fed to and converged inversion again similar to the power equipments such as header box or inverter INVTDeng.

Referring to Fig. 3, realization maximum power point tracking first is illustrated by taking optional two photovoltaic modulies PV_M and PV_N as an exampleThe basic principle of calculation: adjacent or non-conterminous photovoltaic module PV_M and photovoltaic module PV_N is respectively to voltage conversion circuit or electricityPressure converter PO_M and PO_N provide power supply, and voltage conversion circuit is used to execute maximum power tracing to the photovoltaic cell.PhotovoltaicThe transfer efficiency of component or photovoltaic cell is mainly influenced by both sides: first is the internal battery characteristics of photovoltaic cell；SecondIt is periphery the use environment such as sunlight irradiation intensity, load state and temperature condition etc. of battery.Under different external condition, lightVolt battery may operate on different and unique maximum power point, should seek photovoltaic cell under any illumination condition in real time mostExcellent working condition to convert light energy into electric energy to the maximum extent.

Referring to Fig. 3, photovoltaic module PV_M generates desired output voltage using voltage conversion circuit PO_M and is performed simultaneously mostHigh-power point tracking.The first input end NI1 of voltage conversion circuit PO_M is connected to anode and the voltage conversion of photovoltaic module PV_MThe second input terminal NI2 of circuit PO_M is connected to the cathode of photovoltaic module PV_M.Notice the first of voltage conversion circuit PO_MOutput end NO1 is coupled to the unique first node N1 of voltage conversion circuit PO_M, the second output terminal of voltage conversion circuit PO_MThe second node N2 of NO2 coupled voltages conversion circuit PO_M, in addition there are also output capacitance CO to be connected first node N1 and theBetween two node N2.Voltage that photovoltaic module provides is executed the voltage conversion of DC/DC and that is, synchronizes and hold by voltage conversion circuitThe calculation of row maximum power tracing, the DC output voltage that final voltage conversion circuit is exported are generated in voltage conversion circuit PO_MThe first output end and second output terminal between, output voltage load first node N1 and second node N2 between output capacitance COIt is upper.Also that is, output capacitance be connected to the voltage conversion circuit in figure itself first node N1 and second node N2 itBetween.The power switch S1 and power switch S2 of decompression converting circuit BUCK module in voltage conversion circuit PO_M are connected on firstBetween input terminal NI1 and the second input terminal NI2, the power switch of the voltage up converting circuit BOOST in voltage conversion circuit PO_MS3 and power switch S4 is connected between the first output end NO1 and second output terminal NO2.Wherein in decompression converting circuit moduleBoth power switch S1 and power switch S2 are connected in the power in the first interconnecting nodes NX1 and voltage up converting circuit moduleBoth switch S3 and power switch S4 are connected in the second interconnecting nodes NX2, then front side power is opened in Buck-Boost circuit topologyClose the second interconnecting nodes NX2 that both the first connected interconnecting nodes NX1 of both S1-S2 and rear side power switch S3-S4 are connectedBetween be provided with main inductance element L, second output terminal NO2 and the second input terminal NI2 and may be coupled directly to together and set itCurrent potential be a reference potential REF1.Corresponding to the output capacitance CO being arranged between the first output end and second output terminal, the input capacitance CIN that is arranged between the first input end NI1 of converter and the second input terminal NI2.Voltage conversion circuitThe processor of PO_M configuration to directly drive ability weaker, can not sometimes directly drive the switch such as power MOSFET or IGBT,The intensity of switch control signal can be enhanced using the stronger driver/buffer of driving capability again come driving power switch S1-S4。

Referring to Fig. 3, photovoltaic module PV_N generates desired output voltage using voltage conversion circuit PO_N and is performed simultaneously mostHigh-power point tracking, the first input end NI1 of voltage conversion circuit PO_N are connected to anode and the voltage conversion of photovoltaic module PV_NThe second input terminal NI2 of circuit PO_N is connected to the cathode of photovoltaic module PV_N.Pay attention to the voltage conversion circuit PO_N'sFirst output end NO1 is coupled to the unique corresponding first node N1 of voltage conversion circuit PO_N itself and voltage conversionThe second output terminal NO2 of circuit PO_N is coupled to the unique corresponding second node N2 of voltage conversion circuit PO_N itself, separatelyIt is outer to be connected between first node N1 and second node N2 there are one output capacitance CO.Voltage conversion circuit PO_N is by photovoltaicThe voltage of component PV_N executes the voltage conversion of DC/DC simultaneously that is, synchronous execution maximum power tracing calculation, thus final voltageThe DC output voltage that conversion circuit PO_N is exported generates defeated in the first output end NO1 of voltage conversion circuit PO_N and secondBetween outlet NO2 namely output voltage is applied on the output capacitance CO of voltage conversion circuit PO_N.It is equivalent to output capacitance COIt is connected between the first node N1 and second node N2 of the voltage conversion circuit in figure itself.Drop in voltage conversion circuit PO_NThe power switch S1 and power switch S2 of voltage conversion circuit module BUCK is connected on first input end NI1 and the second input terminal NI2Between the two, the power switch S3 and power switch S4 of the booster circuit BOOST in voltage conversion circuit PO_N is connected on firstBetween output end NO1 and second output terminal NO2.Both power switch S1 and power switch S2 of Buck are connected in the first interconnection sectionBoth power switch S3 and power switch S4 in point NX1, Boost module are connected in the second interconnecting nodes NX2, Buck-BoostBoth the first both middle front side power switch S1-S2 connected interconnecting nodes NX1 and rear side power switch S3-S4 be connected secondMain inductance element L is provided between interconnecting nodes NX2, and the second output terminal NO2 and second in voltage conversion circuit PO_NInput terminal NI2 may be coupled directly to the current potential for together and setting them as a reference potential REF2.Equally converted in voltageCorresponding to the output capacitance CO being usually arranged between the first output end NO1 and second output terminal NO2 in circuit PO_N, ifThe input capacitance CIN being placed between the first input end NI1 in voltage conversion circuit PO_N and the second input terminal NI2.Voltage turnsChange the processor of circuit PO_N configuration to directly drive ability weaker, can not sometimes directly drive power MOSFET or IGBT etc.Switch, the intensity that can be enhanced switch control signal using the stronger driver/buffer of driving capability are opened again come driving powerIt closes.

Referring to Fig. 3, if voltage conversion circuit PO_M and voltage conversion circuit PO_N is adjacent and connects, in voltage conversion circuitSeries relationship in, such as: the second node N2 of previous stage voltage conversion circuit PO_M is connected to rear stage voltage conversion circuit PO_The first node N1 of N.Multilevel voltage conversion circuit PO1, PO2 ... PON is connected in series by this rule, any previous step voltageThe second node N2 of conversion circuit PO_M is coupled to the first segment of neighboring later stage voltage conversion circuit PO_N by transmission line LANPoint N1, or the output capacitance CO of any previous stage voltage conversion circuit PO_M are converted by transmission line LAN and neighboring later stage voltageThe output capacitance CO of circuit PO_N connects.The each when series connection such as multilevel voltage conversion circuit PO1-PON that the rest may be inferredOutput capacitance C_OBe connected in series: i.e. the output capacitance CO's and PO3 of the output capacitance CO and PO2 of voltage conversion circuit PO1 is defeatedThe output capacitance CO etc. of capacitor CO ... and PON is connected in series by transmission line LAN out, then concatenated a series of conversion circuit etc.The total tandem voltage provided is equal to the superposition of the voltage on the their own output capacitance CO of voltage conversion circuit PO1-PONValue.

Referring to fig. 2, the electricity of the last level-one of the first node N1 and end of the voltage conversion circuit PO1 of the first first orderTotal tandem voltage of multilevel optimization's device is provided between the second node N2 of voltage conversion circuit PON, the voltage of the first first order turnsThe first node N1 for changing circuit PO1 is the equal of the voltage turn of the equivalent anode of link PO1-PON and the last level-one at endThe second node N2 for changing circuit PON is the equal of the equivalent cathode of link PO1-PON.

Referring to Fig. 3, in order to illustrate this application involves implementation pattern switching scheme spirit, with the realization of diagramFor the electric pressure converter of power conversion, electric pressure converter constitutes decompression list if it is BUCK circuit namely switch S1 and switch S2Arm.In BUCK circuit, the switch S3-S4 of diagram can be abandoned directly from circuit topology, then the main inductance member of BUCK circuitPart L can be connected directly between interconnecting nodes NX1 and the first output end NO1.Or if electric pressure converter works in BUCKState can directly be continuously turned on switch S4 and persistently turn off switch S3, only the power switch S1 and power switch of driving front sideThe switching of S2 high frequency, power converts BUCK circuit can independent work.

Referring to Fig. 3, in order to illustrate this application involves implementation pattern switching scheme spirit, with the realization of diagramFor the electric pressure converter of power conversion, electric pressure converter is that switch S3 and switch S4 constitutes boosting list if it is BOOST circuitArm.In BOOST circuit, switch S1-S2 can be abandoned directly from circuit topology, then the main inductance element L in BOOST circuitIt can be directly coupled between interconnecting nodes NX2 and first input end NI1.Or if electric pressure converter works in BOOST stateSwitch S1 can be directly continuously turned on and persistently turn off switch S2, only the power switch S3 and power switch S4 high of driving rear sideFrequency switches, and the BOOST circuit of power conversion can independent work.

Referring to Fig. 3, for another optional electric pressure converter for realizing power conversion: power switch S1 and S2 are connected onBetween first input end NI1 and the second input terminal NI2, the first output end is connected on using the switch S3 and switch S4 of power tubeBetween NO1 and second output terminal NO2, pay attention to both power switch S1 therein and switch S2 be connected in interconnecting nodes NX1 andBoth power switch S3 and switch S4 are connected in interconnecting nodes NX2, additionally also interconnect in first interconnecting nodes NX1 and secondMain inductance element L is connected between node NX2.Use it as the single armed S1-S2 of the BUCK decompression of prime and as rear class BOOST'sThe single armed S3-S4 that boosts forms BUCK-BOOST circuit, has been provided simultaneously with the power conversion capability of decompression and boosting, the BUCK-BOOST circuit is H bridge type.

Referring to fig. 4, the method that control power optimization device switches between different working modes, transient state are shorted one or manyThe tandem voltage that link belonging to the power optimization device of to be switched operating mode provides；By the power optimization of to be switched operating modeWhether device detecting link, which occurs transient state, is shorted event, is used as by the transient state short circuit event detected from a kind of operating mode and is switched toAnother foundation of operating mode.In one embodiment: the voltage conversion circuit PO1 first node N1 of the first order is the equal ofThe equivalent anode EA of link PO1-PON, N grades of voltage conversion circuit PON second node N2 is the equal of link PO1-PONEquivalent cathode EC.Transient state is shorted belonging to the power optimization device of (transient-short) any one to be switched operating modeLink for example prepares the power optimization device that link voltage conversion circuit PON in the Fig. 4 being shorted belongs to be switched operating mode, electricityVoltage conversion circuit PO1 also belongs to the power optimization device of to be switched operating mode, it is assumed that the link needs the dangerous work from high pressureState is compulsorily entered into safe suspend mode or safe mode, then the voltage conversion circuit of to be switched operating mode will be from originalThe first working condition is switched to second of working condition.It is shorted belonging to the power optimization device of to be switched operating mode about transient stateLink tandem voltage V₁+V₂…+V_NThere are following characteristics: the first node N1 of the voltage conversion circuit PO1 of the first first orderNamely the voltage conversion circuit PON of the last level-one at equivalent anode EA and end second node N2 namely equivalent cathode according toSignal in figure is short-circuited, such as is shorted ST1 for the first time and is shorted ST2 for second, is shorted ST3 for the third time until more numbersShort action be performed, it is a voltage source/stabilization that the link for being in series with multistage dc voltage changer, which substantially remains on,Battery can generate several different effects to short circuit is carried out between its equivalent positive and negative anodes EA-EC, and this effect is made in this applicationFor a kind of instruction.Assigning of instructing is artificial namely us is needed actively to remove short-circuit EA-EC, and the reception of instruction is processor200,200 script of processor mentioned above is turned on and off for the high speed of the power switch of driving voltage conversion circuit, fromAnd the duty ratio of control switch element adjusts output voltage, but here processor 200 also need it is by itself or additionalCan the detecting module of situation of change of monitoring current/voltage/power etc. assist to capture this instruction from link.

Referring to fig. 4, transient state is shorted link belonging to the power optimization device of one or many to be switched operating modes and mentionsThe tandem voltage V of confession₁+V₂…+V_NApproach there are many, using the conductors such as sheet metal or metal tape or conducting wire directly in linkConnection/coupling etc. is attempted between the equivalent positive and negative anodes EA-EC of this battery eliminator, it has to be noted that transient state short circuit means not allowShort circuit duration is connected, and must generally be disconnected at once after short circuit making each time, such as connecting 1 second to 3 seconds at once will be equivalent positive and negativePole it is separated, or connect 6 seconds after disconnect equivalent positive and negative anodes again.

Referring to Fig. 5, describes attempt connection directly between the equivalent positive and negative anodes EA-EC of link using external conductor aboveOr coupling etc. come realize transient state be shorted, in addition to this it is possible between the equivalent positive and negative anodes EA-EC of link setting connection powerSwitch Q.Pay attention to being connected between the equivalent anode EA of link and the positive receiving end of energy collection device and unidirectionally leading as optionLogical diode D, such as the equivalent anode EA of link are connected to the anode of diode D, and the cathode of diode D is connected to energy collection dressThe positive receiving end set.Or the anode of a diode not illustrated is connected to the negative receiving end of energy collection device, and thisThe cathode of a diode not illustrated then is connected to the equivalent cathode EC of link.Energy collection device is inverse in addition to what is be mentioned aboveBecome device or header box etc., can also be the energy storage device etc. with energy-storage battery.This function between the equivalent positive and negative anodes of linkWhat rate switch Q can be the generation of the control units such as similar processor there is high level or low level control signal to drive,Can by directly by it is artificial it is pressed or is touched etc. in a manner of come ON/OFF, the switch artificially controlled typically for example have byButton switch or touch switch or remote control switch etc..Each photovoltaic module PV is each equipped with for executing maximum power point trackingPower optimization device PO, transient state are shorted the tandem of the offer of link belonging to the power optimization device of one or many to be switched operating modesVoltage is shorted event by whether the power optimization device PO detecting link of to be switched operating mode occurs transient state, by what is detectedTransient state is shorted event as the foundation for being switched to other latter operating mode from a kind of upper operating mode.It will be appreciated that trueReal transient state, which is shorted event, just to be allowed to be considered as effectively to be shorted, and various non-genuine transient states are shorted event and then need to be shieldedFall and is regarded as invalid short circuit.Various accident noises present in circuit are likely to that non-genuine transient state is caused to be shorted thingThe presence of part and be detected, for example, electric arc or various similar surge cause the circuit presentation in link may be shorted etc.It is similar to imitate circuit presentation caused by the transient state short circuit of positive and negative anodes EA-EC.

Referring to Fig. 5, transient state connects that power switch Q is one or many, the connection moment: causing to be turned by the voltage of the first orderIt changes between the second node N2 of the first node N1 and N grades of voltage conversion circuit PON of circuit PO1 and is converted comprising multilevel voltageThe link of circuit PO1-PON and the switch Q of connection constitute closed loop.Detecting transient state and being shorted the mode of event includes detecting tandemThe variable quantity of desired indicator that voltage is short-circuited and induces just is considered as when the variable quantity meets preset change conditionTrue transient state is shorted event, and the power optimization device of to be switched operating mode is just switched to another kind from a kind of operating mode at this timeOperating mode.Closed loop LOP is from the first node of the voltage conversion circuit of previous stage to the of previous stage voltage conversion circuitThen two nodes arrive the first node of rear stage voltage conversion circuit and the second node to rear stage voltage conversion circuit again, according toThis analogizes, as a result: being then coupled to N grades of voltage conversion electricity from the first node N1 of the voltage conversion circuit PO1 of the first orderThe second node N2 of road PON, then return to by switch Q the first node N1 of the voltage conversion circuit PO1 of the first order.Desired indicatorThe transient changing rate of the tandem voltage of link is exactly to screen one of foundation when e.g. transient state is shorted, and can be closed in fact by measurementThe transient voltage change rate on cyclization road is measured, and the variable quantity of the transient changing rate of tandem voltage should meet not less than defaultTransient voltage change rate (meeting change condition) be just considered as authentic and valid transient state and be shorted event.The transient changing of voltage,Abbreviation transition, the moment reaction generated when tandem voltage changes the generation of this external interference signal, main includes threeFeature: super-pressure, Instantaneous State, high frequency time.Following three kinds can be classified as according to its performance: being impact transition first, along routeOr the transient voltage wave of circuit propagation, feature are slowly declined after voltage rapid increase.Followed by vibrate transition, signal voltage orSuddenly change of the electric current in stable state, and according to system natural frequencies oscillation and also it can make electric power signal at a very rapid rateAlternately zoom, it will usually decay to zero in one cycle.Furthermore it is voltage waveform notch, continuous voltage oscillation transitionPhenomenon, mains voltage waveform caused by of short duration phase fault distorts in the quick-make and turn off process of control switch.Also for example,Desired indicator be, for example, flow through by transient state be shorted link transient state short circuit current (transient current) be also screen according toOne of according to, the mode that detecting transient state is shorted event includes detecting tandem voltage to be short-circuited and transient state is shorted in the closed loop that inducesThe variable quantity of electric current meets in the variable quantity of transient state short circuit current and is not less than preset transient current value (meeting change condition)When, just it is considered as true transient state and is shorted event rather than accidental accident.Transient state short circuit current and transient state in closed loopVoltage change ratio is mainly that respectively a series of concatenated output capacitance CO are leading by a series of voltage conversion circuit PO1-PON,Therefore the power optimization device of to be switched operating mode or the synchronous detection transient state short circuit current of conversion circuit and transient voltage change ratePrecision can be increased, be not less than preset transient voltage change rate in the variable quantity for meeting transient voltage change rate, while also according withTrue transient state, which is only, when closing the variable quantity of transient state short circuit current not less than preset transient current value is shorted event.Desired indicatorVariable quantity be generally speaking significantly embodied in every short circuit first short circuit electric current and increase a primary and tandem voltage wink of every short circuitState reduces once, this is that transient state is shorted most directly reflecting for event, and processor 200 monitors short circuit current increase/tandem voltageTransient state reduces, and this situation of change of current or voltage has just met preset change condition (increasing or decreasing) in fact,Processor can think that transient state, which has occurred, is shorted event, and measuring transient state short circuit current/transient voltage change rate is only to beIncrease measurement accuracy.

Referring to Fig. 6, the power optimization device or conversion circuit of to be switched operating mode are allowed in different a variety of Working mouldsIt switches under formula, in the battery applications occasion of photovoltaic plant, should export substantially including safe mode and desirably specifiedThe normal mode of operation of voltage.So-called safe mode is to require the voltage of voltage conversion circuit such as PON output very low naturallySo that the tandem voltage that entire link provides is also very low, when the electricity of any one of entire link power optimization device outputPressure is all very low, is just unlikely to constitute potential person threat.For example: the output voltage of power optimization device is consistently less than input voltageSafe mode, be mentioned above power optimization device can be BUCK-BOOST topology so that safe mode can to open upFlutterring work can make its output voltage be lower than the reception voltage supplied by component in decompression mode, simplest mode be make it is at different levelsPower optimization device output voltage is zero most safe.However, power optimization device output voltages at different levels are entirely zero or near zeroAlso there is drawback, it means that DC bus LAN does not have voltage or voltage is approximately zero, and processor 200 receives external command sometimesTime is to need to implement by loading or being injected into the carrier signal on bus, if DC bus is dropped into and is almost equal to zeroCurrent potential, just can not high quality propagation carrier wave, this be negative effect.Therefore other means are the output electricity for making power optimization devicePressure and input voltage ratio clamp down on lower than a preset ratio relationship, such as the voltage conversion circuit PON of certain level-oneOutput voltage VIN comes from component PVN, and its output voltage VN is used for the DC bus that is added to above, limits VN/VINLower than preset ratio relationship RAT such as less than 1/5 or 1/20 etc..It must be recognized that the work of power optimization device is in safe modeOnly of short duration behavior, the main application of power optimization device still modulate its output voltage and export the light that electric current makes pairingComponent operation is lied prostrate in maximum power point.The operating mode of optimizer further includes that power optimization device PO makes the photovoltaic module matched with itPV works in the powerinjected method MPPT mode of maximum power point.

Referring to Fig. 6, the power optimization device or conversion circuit of to be switched operating mode are allowed in different a variety of Working mouldsIt is switched under formula: the several frequently seen work that the first mode MOD1 and second of mode MOD2 and the third mode MOD3 are assumed thatOperation mode, for example the MPPT of maximum power point tracks mode, and safe mode and standby suspend mode, standby suspend mode generally refer to excellentChange that device is standby does not work.200 output switch control signal of processor being mentioned above is used for driving voltage converter namely voltageConversion circuit PO, wherein, the switch control letter of processor output especially typical using pulse-width signal as switch control signalHigh-frequency operation of the power switch (such as S1-S4) between turning on and off in number driving switch power-supply system SMPS, switchPower-supply system is usually to use power semiconductor as switch element, passes through periodical on-off switch, control switch elementDuty ratio adjust output voltage.The control mode of switch control signal is divided into pulse width modulation, pulsewidth modulation and frequencyIt is a variety of to modulate hybrid modulation, pulse frequency modulated etc..In switch power supply system, pass through the switch for generating voltage conversion circuitOperation institute's output voltage is coupled to the input terminal or output end of circuit itself, is further transferred to for providing total tandem voltagePublic direct-current transmission line on.Switch control signal how is utilized to realize electric pressure converter, that is, power optimization device in the first modeSwitching is problem in need of consideration between MOD1 and second of mode MOD2 and the third mode MOD3: changing switch control signalSwitching operating frequency or duty ratio so that the switching operating frequency of the pulse width modulating signal under two kinds of different working modesOr duty ratio is not both one of approach.For example, the switching operating frequency or duty of the switch control signal of driving power optimizerThan reducing, so that it may be switched to second of mode MOD2 such as safety from the tracking mode such as the first mode MOD1 of maximum power pointMode, then the switching operating frequency of the switch control signal of driving power optimizer or duty ratio continue to reduce, so that it may fromSecond of mode MOD2 such as safe mode is directly switch to standby mode such as the third mode MOD3.For example, driving power optimizerSwitch control signal switching operating frequency or duty ratio improve rapidly, so that it may from standby suspend mode such as the third modeMOD3 is switched to the mode such as the first mode MOD1 for executing maximum power point tracking, realizes turn between different mode wherebyIt changes.

Already explained referring to Fig. 5: true transient state, which is shorted event, just to be allowed to be considered as effectively to be shorted, and various non-realReal transient state is shorted event and then needs to be shielded and be regarded as invalid short circuit.In another embodiment, transient state is detectedShort circuit event further includes limiting: the statistics number that tandem voltage is short-circuited in preset period of time meets anticipated number.This is also meanedEven if the processor of power optimization device side detect short circuit event, and the short circuit event times actually occurred have to comply with it is pre-Phase number is just allowed to execution pattern switching, otherwise not switches.Explanation but not is illustrated so that Fig. 5 is particular embodimentAny restrictions are constituted, switch Q is about 3 times by the number that transient state is shorted, and power optimization device detects tandem voltage and is short-circuitedAnd the total degree that the variable quantity and variable quantity of the desired indicator induced meet preset change condition is 3, it means that practical hairRaw short circuit event times comply fully with anticipated number 3 to allow execution pattern to switch, if opposite power optimization device detectingTandem voltage has been arrived to be short-circuited and the variable quantity of desired indicator and variable quantity that induce meet the total degree of preset change conditionWhen being 1 time or 4 times, it is taken as invalid short circuit event and should ignores.In order to monitor and capture and recording voltage/electricityTransient changing phenomenon is flowed, current power quality measuring instrument can be achieved with, and same measuring instrument usually has the following performance:High sampling rate, 10kHz grades of stable state or more, MHz grades of transient state or more.And have high dynamic range: input signal from tens volts to8kV, 20 times of instantaneous variation or more.Certain specification/common recognitions that can be referred to such as similar IEC61000-4-30 define transient voltageMeasurement method: such as envelope method, waveform envelope line range is set based on sine wave, the record as transition goes out clockwork springPart can be used for the monitoring of the transitions such as surge, waveform notch.Such as root-mean-square valve method: quickly sampling very much and be much smaller thanIt is calculated in the interval of one primitive period, which is compared with the threshold value of setting.Such as peak detection: settingOne fixed absolute threshold, instantaneous voltage are more than that this value is transition, for measuring under the models such as surge monitoring.Such as it rollsDynamic window technique: instantaneous value is compared with upper corresponding value of previous period, can be used for monitoring PFC capacitorThe Low frequency transients phenomenon of switching.By taking the Rogowski coil current transformer SR of Fig. 5 measures transient state short circuit current as an example, bus or transmissionLine LAN passes through sensor, mutual inductor SR can the fast-changing harmonic current of measurement promptly and accurately, amplitude is from several amperes to numberKiloampere, range of the frequency at 0.1 hertz to several megahertzs are mainly characterized by between mutual inductor and tested link without directElectrical connection, the measuring signal of mutual inductor SR for example transient state short circuit current can be delivered directly to processor 200 inform processorWhether short circuit event is had occurred, and the measuring instrument of transient voltage can also be conveyed its transient voltage change rate as measuring signalInform whether processor has occurred short circuit event to processor 200.Additionally as option, processor 200 can cooperate voltage to passSensor measurement is shorted the link voltage variation of front and back, before the short circuit that processor measure according to voltage sensor after voltage value and short circuitThen processor itself can calculate voltage change ratio to voltage value, and voltage sensor also has electrical isolation formula, needs to detectThe voltage change of transmission line LAN or bus.In other words, the multiple choices mode provided based on current techniques, as long as can measureThe current sensor of short circuit current and the voltage sensor of measurement transient voltage are suitable for the application.

Referring to Fig. 5, various non-genuine transient states short circuit events are illustrated above and then needs to be shielded and be regarded as in vainShort circuit event.In another embodiment, in order to enhance accuracy of identification, the mode that detecting transient state is shorted event includes detecting stringStep voltage is short-circuited and the variable quantity of desired indicator that induces；And it connects after the one instruction time of the control switch and disconnects rapidly againControl switch；Continue to meet preset change condition and transient state in the variable quantity for detecting desired indicator and be shorted eventTime with instruction the time it is identical when, the power optimization device of to be switched operating mode is identified as true short circuit event.We assume thatThe control switch Q artificially controlled is connected 5 seconds instruction time by force, limits the transient voltage change rate of actual measurementVariable quantity is not less than preset transient voltage change rate VTRAN, and/or limits the variable quantity of the transient state short circuit current of actual measurementNot less than preset transient current value ITRAN, namely the tandem voltage that detects is short-circuited and the variation of desired indicator that inducesPreset change condition before amount must first meet.Before satisfaction under the premise of preset change condition, predetermined finger is being detectedTarget variable quantity meets preset change condition, and (such as transient voltage change rate is not less than VTRAN and/or transient state short circuit currentLower than ITRAN) and transient state be shorted event duration with indicate 5 seconds time it is identical when, i.e. transient voltage change rate is not lowIt is not less than in the substantially 5 seconds duration of VTRAN and/or transient state short circuit current duration substantially 5 seconds of ITRAN, toThe power optimization device of switching working mode just executes the switching of operating mode.It is false in an optional but nonessential embodimentIf: the power optimization device of to be switched operating mode namely the voltage conversion circuit PON of to be switched operating mode are in detecting linkWhen transient state is shorted event, in addition to need to detect tandem voltage be short-circuited and the variable quantity of the desired indicator that induces (such as transient state electricityBuckling rate and/or transient state short circuit current) meet preset change condition, it is necessary to and the voltage for measuring to be switched operating mode turnsThe instantaneous output power of the mating photovoltaic module PVN of circuit PON is changed, only meets the instantaneous defeated of mating photovoltaic module PVN simultaneouslyOut power be approximately equal to zero and the tandem voltage variable quantity of desired indicator that is short-circuited and induces meet preset change condition,It is true effectively short circuit event, the power optimization device PVN of to be switched operating mode is just switched to from a kind of operating mode anotherKind operating mode, otherwise in vain.In optional but nonessential embodiment, it is assumed that the control switch Q being controlled is connect by forceLogical 4 seconds instruction time measured variable quantity of the transient voltage change rate of loop in 4 seconds that Q is connected and is not less than default transient stateVoltage change ratio VTRAN, and/or measure variable quantity of the transient state short circuit current of loop in 4 seconds that Q is connected and be not less than default winkState current value ITRAN, by taking the voltage conversion circuit PO1 of certain to be switched operating mode as an example, sense tandem voltage be short-circuited and(such as transient voltage change rate is not under the premise of preset change condition before the variable quantity of the desired indicator of induction must first meetLower than VTRAN and/or transient state short circuit current are not less than ITRAN) and transient state is shorted event duration and instruction time 4When second is identical, i.e., duration of the transient voltage change rate not less than VTRAN is about 4 seconds and/or transient state short circuit current is not less thanThe duration of ITRAN is about 4 seconds, and the output power of mating photovoltaic module PV1 during which must also be measured in 4 seconds that Q is connectedNamely its export electric current and output voltage product, if during this output power of mating photovoltaic module PV1 be almost equal to zero andOutput power can not be externally provided, voltage conversion circuit PO1 just executes the switching of operating mode.The output electric current of photovoltaic module andOutput voltage can be detected with current detector (such as current divider) and voltage detector (such as divider) respectively.

Referring to Fig. 7, by optimizer, concatenated difference is indirectly with photovoltaic module above: any photovoltaic module is all configuredThere are switching module SH, switching module SH to determine whether its corresponding component PV powers to string group: if switching module is to turn onThen component can power to string group, if switching module is off component do not allow to string group power.With conventional sideCase is similar, and photovoltaic generating system has concatenated multiple photovoltaic module PV1, PV2 ... PVN, they, which are concatenated, constitutes battery pack string,Battery strings group is made of the N grades of photovoltaic module PV1 to PVN being connected in series concatenations.Photovoltaic module is each equipped with execution access or screenThe switching module covered: the photovoltaic voltage that first photovoltaic module PV1 in such as battery strings group is generated is by first switching moduleSH1 decides whether to access in battery strings group, and the photovoltaic voltage that second photovoltaic module PV2 is generated is by second switching module SH2Decide whether to access in battery strings group, until switching module SHN of the photovoltaic voltage that generates of N grades of photovoltaic module PVN by N gradesDecide whether to access in battery strings group.Substantially, the voltage of switching module SH corresponding with every piece of photovoltaic cell output just can be withIt characterizes the photovoltaic cell to provide in the virtual voltage in photovoltaic cell string group: be matched if the component of switching module shielding pairingComponent output voltage be zero, the component output voltage that matches is actual battery if the component of switching module access pairingVoltage.

Referring to Fig. 7, sets in any a string of photovoltaic cell string group and be serially connected with first order photovoltaic module PV1, second level lightComponent PV2 ... to N grades of photovoltaic module PVN of volt, in certain embodiments: first order switching module SH1 is by first order photovoltaicThe photovoltaic electric potential source of battery PV1 exports V when executing access₁₁Or 0 is exported when shielding, second level switching module SH2 is by second level lightThe photovoltaic electric potential source of volt battery PV2 exports V when executing access₂₁Or 0 is exported when shielding, N grades of switching module SHN is by N gradesPhotovoltaic cell PVN voltage execute access when export V_N1Or 0 is exported when shielding.It can be calculated that any one string photovoltaic cellTotal tandem voltage when component all accesses in string group is roughly equal to: first order switching module SH1 output voltage V₁₁In additionSecond level switching module SH2 output voltage V₂₁Then add third level switching module SH3 output voltage V again₂₃... it is added to N gradesSwitching module SHN output DC voltage V_N1, the operation result of tandem voltage is equal to V₁₁+ V₂₁+……V_N1.If someComponent PVK is shielded the output voltage V of then photovoltaic module PVK by its switching module SH K_K1It should just subtract from total tandem voltageIt goes, K is natural number, and most extreme situation is that all components are shielded by respective switching module in battery strings group, then leads to the stringStep voltage is approximately equal to zero.

Referring to Fig. 8, photovoltaic module PV_M executes the switching of access battery strings group using switching module SH_M or executes from electricityThe switching disconnected in the string group of pond.The first input end NI1 of switching module SH_M is connected to the anode and switching mould of photovoltaic module PV_MThe second input terminal NI2 of block SH_M is connected to the cathode of photovoltaic module PV_M.At one optionally but in non-limiting embodiment,It is unique that the first output end NO1 of switching module SH_M can be coupled to switching module SH_M by the current divider not illustrated in figureFirst node N1, the second output terminal NO2 of switching module SH_M can be coupled to switching module by the current divider RS in figureThe unique second node N2 of SH_M.Output capacitance CO can choose that be connected between first node N1 and second node N2 can also be withCapacitor CO is removed in selection.The embodiment of Fig. 8 is using switching module instead of the power optimization device in Fig. 3.Photovoltaic module PV_M'sIn topological structure: access switch SQ1 is coupled between first input end NI1 and the first output end NO1, or access switch SQ1It is coupled between the second input terminal NI2 and second output terminal NO2.It is defeated that removal switch SQ2 in topological structure is then coupled in firstBetween outlet NO1 and second output terminal NO2.If the driving access of the processor 200 switch SQ1 of switching module SH_M configuration is connectedThen photovoltaic module PV_M is just linked into battery strings group and contributes to tandem voltage the voltage segment of oneself, processor 200Also driving removal switch SQ2 is turned off at this time., whereas if the driving of processor 200 of switching module SH_M configuration removes switchSQ2 connects then photovoltaic module PV_M and is just shielded/bypassed from battery pack string, and comes without the tandem voltage of normal direction battery strings groupContribute the voltage segment of oneself, the also driving access switch SQ1 shutdown at this time of processor 200.The second output is paid attention in the embodimentEnd NO2 and the second input terminal NI2 sets their current potential as reference potential REF1.The embodiment of the present embodiment and Fig. 3 is compared, such asThe 4th switch S4 in fruit step-up/step-down circuit PO_M is continuously turned on second switch S2 and persistently turns off, then first switch S1 can be equivalentIt can be equivalent to removal switch for access switch, third switch S3.The step-up/step-down circuit being equivalent in Fig. 3 above is not operate at literThe voltage translative mode of decompression, and it is employed in the switch mode that photovoltaic module is accessed or removed, it is sharp in one embodimentWith the switching module of the topological alternate figures 8 of Fig. 3.

Referring to Fig. 8, photovoltaic module PV_N executes the switching of access battery strings group using switching module SH_N or executes from electricityThe switching disconnected in the string group of pond.The first input end NI1 of switching module SH_N is connected to the anode and switching mould of photovoltaic module PV_NThe second input terminal NI2 of block SH_N is connected to the cathode of photovoltaic module PV_N.At one optionally but in non-limiting embodiment,The first output end NO1 of switching module SH_N can be coupled to switching module SH_N unique first by the current divider RS in figureThe second output terminal NO2 of node N1, switching module SH_N can be coupled to switching module by the current divider not illustrated in figureThe unique second node N2 of SH_N.Output capacitance CO can choose that be connected between first node N1 and second node N2 can also be withCapacitor CO is removed in selection.The embodiment of Fig. 8 is using switching module instead of the power optimization device in Fig. 3.In switching module SH_NTopological structure in: access switch SQ1 be coupled between first input end NI1 and the first output end NO1, or access switch SQ1It is coupled between the second input terminal NI2 and second output terminal NO2.And removal switch SQ2 opposite in topology is then coupled in firstBetween output end NO1 and second output terminal NO2.If the driving access of the processor 200 switch SQ1 of switching module SH_N configuration connectsGeneral rule photovoltaic module PV_N is linked into battery strings group and contributes the voltage segment of oneself to tandem voltage, processor 200 thisWhen also driving remove switch SQ2 be turned off., whereas if the processor 200 of switching module SH_N configuration drives removal switchSQ2 connects then photovoltaic module PV_N and is just shielded/bypassed from battery pack string, and comes without the tandem voltage of normal direction battery strings groupContribute the voltage segment of oneself, the also driving access switch SQ1 shutdown at this time of processor 200.Pay attention to the second output in the embodimentEnd NO2 and the second input terminal NI2 sets their current potential as reference potential REF2.The embodiment of the present embodiment and Fig. 3 is compared, ifThe 4th switch S4 in step-up/step-down circuit PO_N is continuously turned on persistently to be turned off with second switch S2, then first switch S1 is equivalent toAccess switch, third switch S3 can be equivalent to removal switch.The step-up/step-down circuit being equivalent in the Fig. 3 disclosed above does not workIn the voltage translative mode of buck, and it is employed in the switch mode that photovoltaic module is accessed or removed, in one embodimentThe switching module of the middle topological alternate figures 8 using Fig. 3.

Referring to Fig. 8, by taking photovoltaic module PV_M and switching module SH_M as an example, photovoltaic module PV_M is linked into battery strings groupStage its power supply can directly to processor 200 power, if switching module SH_M from connect pattern switching to shutdown mouldThe access switch SQ1 of formula, i.e. switching module SH_M is turned off and is removed switch SQ2 and connect, then the power supply of photovoltaic module PV_M mayIt can not just continue to power to processor 200.Solution: photovoltaic module PV_M is equipped with a matched storage capacitor CS and matches for itThe processor 200 set is powered, the rank that switching module SH_M is even bypassed photovoltaic module PV_M using the removal switch of connectionSection, since storage capacitor CS is electrically charged so can still act as the backup power source of redundancy and power to processor.It is stored up in topologyEnergy capacitor CS is connected between the anode of photovoltaic module PV_M and the reference potential REF1 of photovoltaic module PV_M: the sun of diode DSPole is connected to the anode of photovoltaic module PV_M and connects storage capacitor CS between the cathode and reference potential REF1 of diode DS.Energy storageOne end that capacitor CS is connected with the cathode of diode DS can power for processor 200.Current divider RS as option can be withDetect whether that electric current is flowed in or out from the output end NO1 or NO2 of photovoltaic module PV_M, usually by the electric current of current divider RSTesting result is conveyed to processor 200, hereafter continues to introduce.As option, current divider both ends are respectively coupled to someThe positive and negative port of operational amplifier can be detected to obtain the pressure drop at current divider both ends, current divider using the output valve of amplifierThe pressure drop at both ends substantially can be used to characterize the testing result for the electric current for flowing through current divider.

Referring to Fig. 8, charged from the anode of photovoltaic module PV_M by the diode DS of one-way transmission to storage capacitor CSStorage capacitor can be considered as to redundancy battery.If photovoltaic module PV_N is mating to be also provided with storage capacitor, it must be noted that photovoltaicThe storage capacitor of component PV_N should be connected to photovoltaic module PV_N anode and photovoltaic module PV_N reference potential REF2 itBetween, specifically: the anode of some diode is connected to the anode of photovoltaic module PV_N and the cathode of this diode and reference are electricThe matched storage capacitor of connection photovoltaic module PV_N between the REF2 of position.The storage capacitor CS class of this and photovoltaic module PV_M in Fig. 8Seemingly, but it is noted that the two reference potential is had any different.In addition the current divider RS being related in Fig. 8 is also applied to the liter of Fig. 3In buck topology structure.

Referring to Fig. 8, if switching module SH_M and switching module SH_N is adjacent and connects, connect in the series connection of multistage switching moduleConnect in relationship: the second node N2 of previous stage switching module SH_M is coupled to the first node N1 of rear stage switching module SH_N.Multistage switching module SH1, SH2 ... SHN is connected in series by this rule, the second node of any previous stage switching module SH_MN2 is coupled to the first node N1 of neighboring later stage switching module SH_N by transmission line LAN.Or any previous stage switching moduleThe output capacitance CO of SH_M is connected by the output capacitance CO of transmission line LAN and neighboring later stage switching module SH_N.The rest may be inferred,These capacitors are connected in series if they use output capacitance CO when multistage switching module SH1-SHN is connected in series: cuttingIt changes the mold the output capacitance CO ... of the output capacitance CO and switching module SH3 of the output capacitance CO and switching module SH2 of block SH1 and cutsThe output capacitance CO etc. of mold changing block SHN is connected in series by transmission line LAN, then provided by concatenated a series of switching moduleTotal tandem voltage is equal to the superposition value of the voltage on the their own output capacitance CO of switching module SH1-SHN.But it exportsIt is not necessary to using, they can also abandon capacitor from the topology of each switching module.

Referring to Fig. 9, the first node N1 of the switching module SH1 of the first first order and end is last in multistage switching moduleLevel-one switching module SHN second node N2 between the tandem voltage of multistage switching module is provided, the first first order is cutThe first node N1 of mold changing block SH1 is the equal of the switching mould of the equivalent anode of link SH1-SHN and the last level-one at endThe second node N2 of block SHN is the equal of the equivalent cathode of link SH1-SHN.

Referring to Fig. 9, control the method that switching module switches between different working modes, transient state be shorted it is one or many toThe tandem voltage that link belonging to the photovoltaic module of switching working mode provides, the photovoltaic module of to be switched operating mode and its cutsWhether the processor detecting link of mold changing block configuration, which occurs transient state, is shorted event, is shorted event as photovoltaic by the transient state detectedComponent is switched to the foundation of another operating mode (such as removal) from a kind of operating mode (such as access).It is optional but it is non-mustIn the embodiment of palpus: the first node N1 of the switching module SH1 of the first order is the equal of the equivalent anode EA of link SH1-SHN,The switching module SHN second node N2 of N grades of end is the equal of the equivalent cathode EC of link SH1-SHN.With it is similar above,Transient state is shorted link belonging to the photovoltaic module of (transient-short) any one to be switched operating mode, for example preparesPhotovoltaic module PVN belongs to some photovoltaic module of to be switched operating mode in battery strings group in Fig. 9 of short circuit, either access electricityPond string group is still removed from battery strings group, is all that the switching module SHN of the pairing that control it turns on and off to realize.Photovoltaic module PVN belongs to be switched operating mode, is switched to removal or vice versa from access.It is assumed that photovoltaic module PVN need fromThe excess temperature abnormal operation that access phase generates is compulsorily entered into the suspend mode or safe mode of the safety in removal stage, then to be cutThe photovoltaic module PVN for the mode that changes jobs will be switched to second of working condition from the first initial working condition.Transient state is shortReceive the tandem voltage V of link belonging to the photovoltaic module PVN of switching working mode₁₁+V₂₁…+V_N1There are following characteristics: firstThe switching module SHN's of the last level-one at the first node of the switching module SH1 of the first order namely equivalent anode EA and endSecond node namely equivalent cathode are short-circuited according to the signal in figure, such as first time short circuit ST1 and second of short circuit ST2,Third time short circuit ST3 is performed up to the short action of more numbers, is in series with the chain of multistage photovoltaic module or switching module SHRoad is substantially still a voltage source/stabilization battery, between its equivalent positive and negative anodes EA-EC carry out short circuit can generate it is several notSame effect, this effect are used as a kind of instruction in this application.Assigning of instructing is that artificial to need us actively to go shortRoad EA-EC, the reception of instruction are the matched processors 200 of switching module SH.200 script of processor mentioned above is for drivingSwitching module removal switch and access switch turn on and off, but here processor 200 also need it is by itself orIt is additional can the detecting module of situation of change of monitoring current/voltage/power etc. assist to capture this instruction from link.

Referring to Fig. 9, transient state is shorted link belonging to the photovoltaic module PVN of one or many to be switched operating modes and mentionsThe tandem voltage V of confession₁₁+V₂₁…+V_N1Approach there are many, using the conductors such as sheet metal or metal tape or conducting wire directly in chainConnection/coupling etc. is attempted between the equivalent positive and negative anodes EA-EC of this battery eliminator of road, it has to be noted that transient state short circuit means not permitPerhaps short circuit duration connect, generally each time after short circuit making must at once disconnect, such as connect 1 second to 3 seconds at once by it is equivalent justCathode it is separated, or disconnect equivalent positive and negative anodes again or 10 seconds are such as the following after connecting 4-6 seconds, this specific time as justDemonstration does not constitute a limitation.Attempted directly between the equivalent positive and negative anodes EA-EC of link using external conductor connect or couple etc. comeRealize that transient state is shorted, in addition to this it is possible to the setting connection power switch Q between the equivalent positive and negative anodes EA-EC of link.Pay attention toAs option, the diode of one-way conduction is connected between the equivalent anode EA of link and the positive receiving end of energy collection deviceD, the equivalent anode EA of link are connected to the anode of diode D, and the cathode of diode D is connected to the positive receiving end of energy collection device.Or the anode of a diode not illustrated is connected to the negative receiving end of energy collection device, and what this was not illustratedThe cathode of diode is then connected to the equivalent cathode EC of link.Energy collection device is in addition to the inverter or header box that are mentioned aboveDeng can also be the energy storage device etc. with energy-storage battery.This power switch Q between the equivalent positive and negative anodes of link can beWhat the control units such as similar processor generated there is high level or low level control signal to drive, can also be directly by artificialThe modes such as it is pressed or is touched carry out ON/OFF, the switch artificially controlled typically for example has button switch or touch-control to openPass or remote control switch etc..In an alternate embodiment of the invention, it is contemplated that short circuit current caused by short circuit is very big and transient voltage changeRate is also very big, so setting and the concatenated buffer circuit 300 of power switch Q also between equivalent positive and negative anodes EA-EC, it be can wrapCapacitor or resistance are included, is also possible to the RC buffer circuit etc. of resistance and capacitor tandem type, naturally it is also possible to be other kinds ofBuffer circuit, buffer circuit 300 are not required but can be cast out.Photovoltaic module PV is each equipped with for executing accessOr the switching module SH removed, transient state are shorted the matched switching module of photovoltaic module PV of one or many to be switched operating modesWhether the processor detecting link of the tandem voltage that link belonging to SH provides, the photovoltaic module PV of to be switched operating mode occursTransient state is shorted event, is shorted event by the transient state that detects and is used as and is switched to other latter from a kind of upper operating mode and worksThe foundation of mode.We are and various non-real it will be appreciated that true transient state is shorted event just allows to be considered as effectively to be shortedReal transient state is shorted event and then needs to be shielded and be regarded as invalid short circuit.

Referring to Fig. 9, it is one or many that transient state connects power switch Q, at the connection moment: leading to the switching by the first orderInclude multistage switching module SH1- between the second node N2 of the first node N1 and N grades of switching module SHN of module SH1The link of SHN and the switch Q of connection constitute closed loop.Detecting transient state and being shorted the mode of event includes that detecting tandem voltage is shortRoad and the variable quantity of desired indicator induced is just considered as true transient state and is shorted when variable quantity meets preset change conditionEvent, the photovoltaic module of to be switched operating mode is just switched to another operating mode from a kind of operating mode at this time.Close ringRoad is mainly the second node of the switching module from the first node of the switching module of previous stage to previous stage then again to latterThe first node of the switching module of grade and the second node of the switching module to rear stage, as a result: from the switching module of the first orderThe first node N1 of SH1 is coupled to the second node N2 of N grades of switching module SHN, then returns to cutting for the first order by switch QChange the mold the first node N1 of block SH1.There are two types of the first nodes to the circuit of its second node of the switching module of any level-oneSelection: first node is direct by removal switch SQ2 when the first is exactly removal switch SQ2 connection but access switch SQ1 shutdownPenetrate into its second node；Second is exactly when removing switch SQ2 shutdown but access switch SQ1 connection, to be switched by accessThe access of SQ1 and photovoltaic module makes the first node of switching module be coupled to its second node by component.Such as transient stateIts transient voltage change rate can be considered as predetermined finger when being shorted the tandem voltage that the multistage switching module link with component providesOne of mark, the variable quantity of the transient changing rate of tandem voltage, which should meet, (meets change not less than preset transient voltage change rateChange condition) just it is considered as authentic and valid transient state short circuit event.Also for example desired indicator is to flow through the biography for the link being shorted by transient stateTransient state short circuit current on defeated line LAN, the mode that detecting transient state is shorted event includes that detecting tandem voltage is short-circuited and inducesThe variable quantity of transient state short circuit current in closed loop meets in the variable quantity of transient state short circuit current and is not less than preset transient currentWhen value (meeting change condition), just it is considered as true transient state and is shorted event rather than accidental accident.Wink in closed loopState short circuit current and transient voltage change rate are mainly by a series of a series of corresponding photovoltaic groups of switching module SH1-SHNPart PV1-PVN is leading, thus the photovoltaic module of to be switched operating mode or the synchronous detection transient state short circuit current of switching module andTransient voltage change rate can increase precision, become in the variable quantity for meeting transient voltage change rate not less than preset transient voltageRate, while while also being compliant with the variable quantity of transient state short circuit current not less than preset transient current value, is only true transient state and is shortedEvent.By taking the current transformer SR of Fig. 5 measures transient state short circuit current as an example, bus or transmission line LAN pass through mutual inductor, mutual inductorSR can the fast-changing transient current value of measurement promptly and accurately, for example transient state short circuit current can directly transport the signal of measurementInform whether processor has occurred short circuit event to processor 200.Processor 200 can cooperate voltage sensor measurement to be shorted front and backTandem voltage change, before the short circuit that processor is measured according to voltage sensor voltage value and after being shorted voltage value then processor fromBody can calculate voltage change ratio.Sensor for transient voltage measurement belongs to known technology.It in other words, as long as canThe voltage sensor of the current sensor and measurement transient voltage that measure short circuit current is suitable for the application.

Referring to Fig. 9, in order to enhance accuracy of identification, in an alternate embodiment of the invention, the mode that detecting transient state is shorted event includesDetecting tandem voltage is short-circuited and the variable quantity of desired indicator that induces；And it connects fast again after the one instruction time of the control switchControl switch is opened in quick-break；To meet preset change condition and transient state short circuit event in the variable quantity for detecting desired indicatorWhen duration is identical as the instruction time, the processor that the photovoltaic module of to be switched operating mode is configured just is identifiedTo be really shorted event.We assume that the control switch Q artificially controlled is connected 2 seconds instruction time by force, limit realThe variable quantity of the transient voltage change rate of border measurement is not less than preset transient voltage change rate VTRAN, and/or limits practical surveyThe variable quantity of the transient state short circuit current of amount is short not less than preset transient current value ITRAN, namely the tandem voltage detectedPreset change condition before road and the variable quantity of desired indicator induced must first meet.Preset change condition before satisfactionUnder the premise of, meeting preset change condition in the variable quantity for detecting desired indicator, (such as transient voltage change rate is not less thanVTRAN and/or transient state short circuit current are not less than ITRAN) and transient state short circuit event duration and instruction 2 seconds time phaseMeanwhile that is, duration substantially 2 second of the transient voltage change rate not less than VTRAN and/or transient state short circuit current are not less thanThe duration of ITRAN substantially 2 seconds, the photovoltaic module PV of to be switched operating mode just executed the switching of operating mode: namelyIts matched switching module SH switches to removal state or access state.In optional but nonessential embodiment, it is assumed thatThe processor 200 of its configuration of the photovoltaic module PVN of to be switched operating mode is when the transient state for detecting link is shorted event, in addition to wantingDetecting tandem voltage is short-circuited and the variable quantity (such as transient voltage change rate and/or transient state short circuit current) of desired indicator that inducesMeet preset change condition, also needs the instantaneous output power for the photovoltaic module PVN for additionally measuring to be switched operating mode, onlyThe instantaneous output power for simultaneously meeting photovoltaic module PVN is approximately equal to zero and tandem voltage is short-circuited and the desired indicator that inducesVariable quantity meets preset change condition, is only true effectively short circuit event, the photovoltaic module PV of to be switched operating mode isRemoval mode is switched to from access module or on the contrary, is otherwise considered as invalid instruction and is not switched.In an alternative embodiment: controlSystem switch Q is switched on 1.2 seconds instruction time, and variable quantity of the transient voltage change rate in 1.2 seconds that Q is connected is not less than defaultThe variable quantity of transient voltage change rate VTRAN and/or transient state short circuit current in 1.2 seconds that Q is connected is not less than default transient state electricityFlow valuve ITRAN is sensed tandem voltage and is short-circuited and is induced using the photovoltaic module PV1 of certain to be switched operating mode as exampleDesired indicator variable quantity first to meet before (such as transient voltage change rate is not less than under the premise of preset change conditionVTRAN and/or transient state short circuit current are not less than ITRAN) and transient state short circuit event duration and instruction the time 1.2 secondsWhen identical, i.e., duration of the transient voltage change rate not less than VTRAN is about 1.2 seconds and/or transient state short circuit current is not less thanThe duration of ITRAN is about 1.2 seconds, during which Q connect 1.2 seconds in measure photovoltaic module PV1 output power namely itsExport electric current and output voltage product, if during this output power of mating photovoltaic module PV1 be almost equal to zero and can not be rightOuter offer output power, switching module SH1 just execute the pattern switching for being linked into and removing or remove to access.

Referring to Fig. 9, as long as there there is no the photovoltaic module of some in each photovoltaic module PV1-PVN in battery strings groupBy its matched switching module to bypassing, then there is voltage between equivalent anode and equivalent cathode EA-EC, so passing throughTransient state is shorted one or many tandem voltages, and then processor 200 detects the variation of desired indicator namely the increase of short circuit currentAnd/or the transient state of tandem voltage reduces, so processor 200 executes corresponding behaviour as instruction according to the variation of desired indicatorMake: event being shorted as foundation by the transient state detected and connects SQ1 and shutdown SQ2 and photovoltaic module is linked into battery strings groupIn, or the transient state by detecting be shorted event as foundation and turn off SQ1 with connect SQ2 and by photovoltaic module from battery strings groupIt removes.Consider the problem of another reality: being linked into the photovoltaic module number of battery strings group in each photovoltaic module PV1-PVNIt measures very few or even all photovoltaic module PV1-PVN to be all bypassed, then the string between equivalent anode and equivalent cathode EA-ECStep voltage just very small even zero, the transient state of the increase and/or tandem voltage that lead to short circuit current reduce unobvious or even pre-Determining index does not have any variation, just becomes difficult then switching.For example, if being that access state-SQ1 connects before photovoltaic moduleLogical/SQ2 shutdown, is shorted the instruction that event is assigned by transient state later and is switched to so that photovoltaic module enters suspend mode/standby mode-SQ1 shutdown/SQ2 is connected, the tandem voltage between equivalent anode and equivalent cathode EA-EC just very small even zero, at this time againThe instruction that event is assigned is shorted with transient state just not working, it can the setting point in switching module SH topology due to being mentioned aboveDevice RS is flowed, a solution is at this time: generating potential difference in battery strings group, such as in equivalent anode and equivalent cathode EA-Potential difference is generated between EC, is switched on due to the removal switch of the switching modules at different levels in the state of being removed, so passingInjection Current will be generated on defeated line LAN and each current divider RS, if processor 200 sensed Injection Current will be againConnect access switch SQ1.Here in two kinds of situation: switching module SH1-SHN is all turned on to remove switch SQ2 and turn off access and openClose SQ1；Either another situation: the removal switch SQ2 of part switching module is connected and access switch SQ1 shutdown, remaining anotherThe removal switch SQ2 shutdown of a part of part switching module is connected with access switch SQ1, is accessed switch SQ1 at this time and is in accessWhat the removal switch SQ2 of the switching module of state is off but its access switch SQ1 was to turn on, so first node and secondIt is still to turn between node, so Injection Current still is able to be split device RS and effectively detect.It is equivalent anode andPotential difference is generated between equivalent cathode EA-EC to be easy to, and potential difference, simpler side can be directly generated using other power supplysCase is that the application based on photovoltaic module has used inverter INVT of Fig. 1 etc., thus inverter INVT it is reversed equivalentPotential difference is generated between positive and equivalent cathode EA-EC.

Referring to Fig. 3, persistently turned off if the 4th switch S4 of voltage conversion circuit PO_M is continuously turned on second switch S2Interpreted above: then first switch S1 can be equivalent to access switch, third switch S3 can be equivalent to removal switch,The original step-up/step-down circuit function of so voltage conversion circuit PO_M is cancelled, and as alternative functions, it can be considered as photovoltaic groupSwitching module part PV_M access or removed, similar to the switching module SH_M of Fig. 8.Substantially no matter voltage conversion circuit is used asOriginal step-up/step-down circuit is also used as switching module, is likely to so that tandem voltage very faint even zero, such as originalStep-up/step-down circuit/power optimization device is in standby/dormant state, the output voltage very little of voltage conversion circuit by processor controlEven zero, then total tandem voltage also very little.Such as voltage conversion circuit is used as switching module, each photovoltaic module PV1-The photovoltaic module quantity that the voltage conversion circuit that PVN is used as switching module in the middle is linked into battery strings group is very few, or even hasMay all photovoltaic module PV1-PVN be all bypassed, then the tandem voltage between equivalent anode and equivalent cathode EA-EC is just verySmall even zero.If voltage conversion circuit was shorted the instruction that event is assigned by transient state later from the mode of maximum power tracingBeing switched to makes voltage conversion circuit enter suspend mode/standby mode, and the tandem voltage between equivalent anode and equivalent cathode EA-EC is justVery small even zero, at this time again with transient state be shorted the instruction assigned of event require voltage conversion circuit be restored to powerinjected method orSafe mode does not just work.Current divider RS can be set in voltage conversion circuit topology due to being mentioned above, useThe voltage conversion circuit for making switching module can be by the electric current with identical detection current divider RS above come from standby/suspend mode mouldFormula is restored to the operating mode of powerinjected method.Another solution for restoring powerinjected method mode of voltage conversion circuit is:Potential difference is generated in battery strings group, potential difference, standby voltage conversion are generated between equivalent anode and equivalent cathode EA-ECThe output voltage of circuit is all nearly equal to zero, and generating will be because of the current potential of application on moment each output capacitance CO of potential differenceDifference generates the pulse of transient state, if processor 200 has sensed the pulse generated and voltage conversion circuit will be driven to execute most againHigh-power tracking, the sensing of spike belong to mature technology in the detection means of the prior art.Very based on tandem voltageSmall even zero the case where, when the corresponding voltage conversion circuit of at least part photovoltaic module in battery strings group is inWhen suspend mode/standby, photovoltaic module is switched to the mode of maximum power tracing mode from suspend mode/standby mode are as follows: firstThe second output terminal of the voltage conversion circuit PON of the first output end and end afterbody of voltage order one conversion circuit PO1 itBetween generate potential difference, can reversely generate potential difference by inverter, when photovoltaic module configuration processor sense output capacitanceCO is upper because when applying spike caused by instant electric potential difference, is just restored to powerinjected method mode from suspend mode/standby.

Above by the content of description and accompanying drawings, the exemplary embodiments of the specific structure of specific embodiment are given, onIt states invention and proposes existing preferred embodiment, but these contents are not intended as limiting to.For a person skilled in the art,After reading above description, various changes and modifications undoubtedly be will be evident.Therefore, appended claims should be regarded as and coverWhole variations and modifications of true intention and range of the invention.The range of any and all equivalences in Claims scopeWith content, all it is considered as still belonging to the intent and scope of the invention.

Claims (10)

1. a kind of realize the switching method that photovoltaic module is accessed or removed in battery strings group, it is characterised in that:

Battery strings group includes the multiple photovoltaic modulies being connected in series；

Each photovoltaic module, which is each equipped with, couples access switch in battery strings group for photovoltaic module and by photovoltaic moduleThe removal switch shielded from battery strings group；

The method includes:

Transient state is shorted the tandem voltage of the offer of battery strings group belonging to one or many to be switched photovoltaic modulies；

Whether the processor detecting battery strings group of to be switched photovoltaic module configuration, which occurs transient state, is shorted event, by what is detectedTransient state is shorted event as the foundation for judging that photovoltaic module is accessed or removed from battery strings group.

2. according to the method described in claim 1, it is characterized by:

The mode that detecting transient state is shorted event includes the variable quantity of desired indicator for detecting tandem voltage and being short-circuited and inducing；

When the variable quantity meets preset change condition, to be switched photovoltaic module from access or remove one of modeIt is switched to another mode.

3. according to the method described in claim 2, it is characterized by:

The desired indicator includes at least transient state and is shorted the transient state short circuit current generated and/or leads to tandem including transient state short circuitThe transient changing rate of voltage.

4. according to the method described in claim 1, it is characterized by:

It further includes limiting that detecting transient state, which is shorted event:

The statistics number that tandem voltage is short-circuited in preset period of time meets anticipated number.

5. according to the method described in claim 1, it is characterized by:

The switching module for realizing that each photovoltaic module is accessed or removed from battery strings group includes:

The corresponding positive and negative anodes for being respectively coupled to corresponding photovoltaic module of first, second input terminal；

Access switch is coupled between first input end and the first output end or between the second input terminal and second output terminal；

Switch is removed to be coupled between the first output end and second output terminal；

When multistage switching module is connected in series, the second output terminal of any previous stage switching module is coupled to neighboring later stage switchingFirst output end of module；To

Total tandem voltage that multistage switching module provides be equal in it the first output end of first first order switching module andThe superposition value of voltage between the second output terminal of the switching module of end afterbody.

6. according to the method described in claim 5, it is characterized by:

At least part photovoltaic module in battery strings group bypass by respective removal switch when being shorted, and photovoltaic module is from shiftingExcept the mode of pattern switching to access module are as follows:

Between the second output terminal of the switching module of the first output end and end afterbody of first first order switching modulePotential difference is generated, is restored to access module when the processor of photovoltaic module configuration senses the Injection Current of potential difference generation.

7. according to the method described in claim 6, it is characterized by:

Any one switching module is coupled between its first output end and the second output terminal of previous stage switching module and is used forSense the current divider of Injection Current；Or

Any one switching module is coupled between its second output terminal and the first output end of rear stage switching module and is used forSense the current divider of Injection Current.

8. according to the method described in claim 5, it is characterized by:

Each photovoltaic module is equipped with a storage capacitor as the processor power supply of its configuration, passes through from the anode of photovoltaic moduleThe diode of one-way transmission charges to storage capacitor.

9. according to the method described in claim 5, it is characterized by:

The first output end of first first order switching module and the afterbody at end in concatenated multistage switching module switchControl switch is coupled between the second output terminal of module；

The mode that transient state is shorted is implemented to the tandem voltage that battery strings group provides are as follows:

It is disconnected rapidly after connecting the control switch.

10. according to the method described in claim 9, it is characterized by:

The mode that detecting transient state is shorted event includes the variable quantity of desired indicator for detecting tandem voltage and being short-circuited and inducing；And

It connects and disconnects control switch after the one instruction time of the control switch rapidly again；To

Meet preset change condition in the variable quantity for detecting desired indicator and transient state is shorted event duration and instituteState instruction the time it is identical when, the switching of to be switched photovoltaic module ability execution pattern.