A kind of battery wireless charging system of high-order combined type compensation networkTechnical field
The invention discloses a kind of battery wireless charging systems of high-order combined type compensation network, are related to battery wireless chargingTechnology is suitable for the batteries wireless charging occasions such as electric car and medical instrument.
Background technique
Wireless charging technology is easy to use because not connecting electrically and mechanically between feeder ear and receiving end and safety canIt leans on, therefore, there is great application prospect.Battery charging generally includes two stages of constant-current charge and constant-voltage charge, therefore, nothingLine charge electric system need to provide it to battery needed for constant current and constant voltage output.
The loosely coupled transformer coefficient of coup used in wireless charging system is low, leakage inductance value is big, in circuit unavoidablyGround generates reactive circular power flow, increases stresses of parts and loss, therefore, it is necessary to compensate its quadergy, is generally mended using capacitorRepay the quadergy of transformer leakage inductance generation.In entire battery charging process, the equivalent load of battery is in a very big modelInterior variation is enclosed, required constant current or constant voltage output are realized in wide loading range and guarantees zero quadergy or zero input phaseControl means used by parallactic angle (Zero Phase Angle, ZPA) are typically only capable to realize a control target.Therefore, very muchResearch takes into account more than two control targets using the characteristic of compensation circuit itself, for example, under particular job frequency, string string(SS) and and simultaneously (PP) realize the output constant current unrelated with load simultaneously and input ZPA, and string simultaneously (SP) and and go here and there (PS) can be withThe output constant pressure unrelated with load and input ZPA are realized simultaneously, and therefore, charging system, which can work, is determining frequency state, simplified control.
At present, it has been suggested that realized by way of compound above-mentioned four kinds of Basic Topologicals after first constant current the output of constant pressure andInput ZPA.For example, two kinds of basic topologies of SS/PS or PP/SP are compound by switching switch progress, by switching switchThe output and idle full compensation of constant pressure after first constant current may be implemented in control, and above two composite construction is in different operating modesUnder compensating parameter and resonance frequency having the same, it is possible to reduce compensation device and switching switch, still, mode selector switchIn primary side side, therefore, the control of mode switch need to carry out signal transmission, control by the communication system between transmitting terminal and receiving endMake relative complex, reliability is low.The shortcomings that based on primary side composite construction, mode selector switch is placed on secondary side by existing research,As two kinds of composite constructions of SS/SP or PP/PS need to increase additional compensation device since compensation frequency and parameter are not fully identicalConstant current or constant voltage output and idle full compensation could be realized simultaneously.The above composite construction is based on four kinds of basic collocation structures,Coil design needs to consider loading condition, and coil design is restricted, and parameter designing freedom degree reduces.
Based on above-mentioned Compound Topology structure there are the problem of, existing research propose on the basis of bilateral LCC, pass through changeThe working frequency of charging system realizes the output and idle full compensation of constant pressure after first constant current, but existing Specification fillsThe working frequency of electric system, if working frequency exceeds given frequency range, this method be cannot achieve, and there is still a need for former secondary sides to communicateIt realizes the change of primary side side frequency, reduces the reliability of system.
By being analyzed above it is found that the switching of secondary edge mode, approximate zero quadergy and constant current-constant pressure can be achieved at the same time at present is defeatedComposite construction out, however it remains the problem of loosely coupled transformer parameter of output constant current or constant pressure is limited by loading condition,By the output of constant pressure after the first constant current of change system operating frequency realization and the idle method compensated entirely, there is also systems to work frequentlyThe problem of rate is limited and reliability reduces.
Summary of the invention
Goal of the invention of the invention is the deficiency for above-mentioned background technique, provides a kind of high-order combined type compensation networkBattery wireless charging system, by secondary edge mode change-over switch can constant frequency realize load needed for first constant current after constant pressureOutput and reactive power are approximately the Sofe Switch of zero and switching device, and improve compensation network coil design freedomAnd system reliability, it solves existing combined compensation structure and realizes that the coil parameter design of constant current or constant pressure is limited by loading conditionThe technical problem that system and system operating frequency are limited.
The present invention adopts the following technical scheme that for achieving the above object
The battery wireless charging system of high-order combined type compensation network, including sequentially connected high frequency full bridge inverter,Primary side compensation network, loosely coupled transformer, secondary side compensation network, constant current-constant voltage mode handover network, full-bridge rectifier filter electricityRoad.
Wherein, primary side compensation network includes: that primary side compensation inductance, primary compensation capacitor and primary side additional capacitor, secondary side are mendedRepaying network includes: the secondary compensating electric capacity when compensating inductance, pair and the first secondary additional capacitor in additional capacitor, the second pair, constant current-Constant voltage mode handover network includes: first switch, second switch.
One end of primary side compensation inductance is connect with a bridge arm midpoint of high frequency full bridge inverter, and primary side compensates the another of inductanceOne end, primary compensation capacitor a pole of an extremely equal primary side additional capacitor be connected, another pole of primary side additional capacitor and loose couplingClose one end connection of transformer primary winding, another pole of primary compensation capacitor, loosely coupled transformer primary side winding the other endIt is connected with another bridge arm midpoint of high frequency full bridge inverter.One pole of the first secondary side additional capacitor and loosely coupled transformerOne end of vice-side winding connects, and the second secondary pole in additional capacitor is connect with another pole of additional capacitor when the first pair, and secondSecondary another pole in additional capacitor is connected with one end of a pole of compensating electric capacity when pair and secondary side compensation inductance, secondary side compensation electricityAnother pole held connects one end of second switch, the other end of secondary side compensation inductance and a bridge arm midpoint of full-bridge rectification filter circuitConnection, the other end, the other end of second switch of loosely coupled transformer vice-side winding are another with full-bridge rectification filter circuitThe connection of bridge arm midpoint, first switch are attempted by between the two poles of the earth of the second additional capacitor.
Primary side compensate inductance, primary compensation capacitor, it is secondary while compensate inductance, it is secondary while compensating electric capacity parameter according toWithIt chooses, primary side additional capacitor, the first secondary sideThe parameter of additional capacitor according toWithIt chooses, ω is the angular frequency of system work, MFor loosely coupled transformer mutual inductance, D is duty ratio, VINFor input direct-current voltage, VBATCharging voltage, I are given for batteryBATFor batteryGiven charging current, LPFor loosely coupled transformer primary side self-induction, LSFor loosely coupled transformer pair side self-induction, L1Electricity is compensated for primary sideSense, L2Inductance, C are compensated for secondary sidePFor primary compensation capacitor, CSFor secondary side compensating electric capacity, C1To be connected on loosely coupled transformer originalThe primary side additional capacitor of side winding, C2For the first secondary side additional capacitor being connected on loosely coupled transformer vice-side winding, in addition,C3For another additional capacitor in secondary side, and C3=0.5CS。
The battery wireless charging system of high-order combined type compensation network is closed first switch S in the constant-current phase of charging1WithSecond switch S2It is closed, circuit is LCC-LCC compensation way, and charging system enters constant current mode, and output is negative with batteryCarry unrelated constant current IBAT:Input impedance ZIN:
In the constant-voltage phase of battery charging, first switch S is disconnected1With second switch S2, circuit topology is LCC-S compensation, is filledElectric system enters constant pressure operating mode, exports the constant voltage V unrelated with cell loadBAT:Input impedance ZIN:
More than, IOpeakCurrent peak, V are exported for exchange sideOpeakTo exchange side output voltage peak value, R is the equivalent electricity of batteryResistance.
The present invention by adopting the above technical scheme, has the advantages that
(1) the invention proposes a kind of battery wireless charging system of high-order combined type compensation network, high-order compensation is utilizedThe circuit intrinsic propesties of network realize constant current output or constant voltage output under specific frequency, are opened by controlling its secondary edge mode switchingPass can realize constant voltage output after the first constant current unrelated with load directly under identical specific frequency, and working frequency can be adjustedIt is whole, it is ensured that without departing from given frequency range, existing Compound Topology constant current and the adjustable parameter of constant voltage output can be overcome to setThe method of setting is limited to working frequency and needs the defect of primary side communication device, improves system reliability.
(2) be under two kinds of output modes high-order compensation network wireless charging system can be not only restricted to transformer ginsengNumber exports any constant pressure or constant current, improves energy transmission coil design freedom, by secondary side signal feedback control quantity compared withThe switching of constant current mode and constant voltage mode can be realized in few secondary edge mode switching switch, avoids improving while complex communicationThe reliability of system can overcome the wireless charging system coil design based on secondary side combined type compensation network limited and reliableProperty reduce defect.
(3) in entire charging process, converter input impedance is approximately purely resistive, avoids reactive circular power flow, reduces deviceStress, while realizing the Sofe Switch of switching device, it improves efficiency.
Detailed description of the invention
Fig. 1 is the topology diagram of the battery wireless charging system of high-order combined type compensation network.
Fig. 2 (a), Fig. 2 (b) are the current waveform figure and voltage oscillogram of high-order Compound Topology rectification front and back respectively.
Fig. 3 is that high-order Compound Topology works under constant current mode, the v when equivalent resistance of battery is 15 Ωgate、vAB、iINAnd IBATWaveform diagram.
Fig. 4 is that high-order Compound Topology works under constant current mode, the v when equivalent resistance of battery is 25 Ωgate、vAB、iINAnd IBATWaveform diagram.
Fig. 5 is that high-order Compound Topology works under constant current mode, the v when equivalent resistance of battery is 33 Ωgate、vAB、iINAnd IBATWaveform diagram.
Fig. 6 is that high-order Compound Topology works under constant voltage mode, the v when equivalent resistance of battery is 33 Ωgate、vAB、iINAnd VBATWaveform diagram.
Fig. 7 is that high-order Compound Topology works under constant voltage mode, the v when equivalent resistance of battery is 70 Ωgate、vAB、iINAnd VBATWaveform diagram.
Fig. 8 is that high-order Compound Topology works under constant voltage mode, the v when equivalent resistance of battery is 100 Ωgate、vAB、iINAnd VBATWaveform diagram.
Figure label explanation: 1 is high frequency full bridge inverter, and 2 be primary side compensation network, and 3 be loosely coupled transformer, and 4 areSecondary side compensation network, 5 be constant current-constant voltage mode handover network, and 6 be full-bridge rectification filter circuit, and 7 be load battery, Q1、Q2、Q3、Q4For the first, second, third, fourth power tube, S1、S2For the first, second switch, L1Inductance, L are compensated for primary side2For secondary sideCompensate inductance, CPFor primary compensation capacitor, CSFor secondary side compensating electric capacity, C1For primary side additional capacitor, C2、C3For the first, second pairSide additional capacitor, D1、D2、D3、D4For the first, second, third, fourth diode, CfFor output filter capacitor.
Specific embodiment
The technical solution of invention is described in detail with reference to the accompanying drawing.
A kind of battery wireless charging system of high-order combined type compensation network disclosed by the invention is as shown in Figure 1, comprising: highFrequency full bridge inverter 1, primary side compensation network 2, loosely coupled transformer 3, secondary side compensation network 4, constant current-constant pressure handover network 5,Full-bridge rectification filter circuit 6.Constant current-constant voltage mode handover network 5 includes: first switch S1, second switch S2.High frequency full-bridge is inversePower transformation road 1 includes the first power tube Q1, third power tube Q3A bridge arm and the second power tube Q for composition2, the 4th power tubeQ4Another bridge arm of composition, the first power tube Q1, third power tube Q3Tie point be bridge arm midpoint A, the second power tube Q2、4th power tube Q4Tie point be bridge arm midpoint B.Full-bridge rectification filter circuit 6 includes first diode D1, third diode D3A bridge arm and the second diode D for composition2, the 4th diode D4Another bridge arm of composition, output filter capacitor CfIt is attempted byThe output end of full-bridge rectification filter circuit 6, load battery 7 are attempted by output filter capacitor CfBetween the two poles of the earth.
In high-order Compound Topology structure shown in FIG. 1: as first switch S1With second switch S2When closure, circuit is in perseveranceCurrent charge state, input impedance ZINForExport the constant current unrelated with cell loadLCC-LCC compensation network is high-order compensation network, and therefore, system exports under specific frequencyIt constant current and transformer parameter can be not only restricted to exports any constant current；As first switch S1With second switch S2When disconnection, at circuitIn constant-voltage charge state, input impedance ZINForExport the constant voltage unrelated with cell loadR is battery equivalent resistance, and LCC-S compensation network is high-order compensation network, and therefore, system is specificConstant pressure is exported under frequency and can be not only restricted to transformer parameter exports any constant pressure.
When battery starts to charge, constant current charging mode is initially entered, electric current is maintained at IBAT, while voltage constantly rises, directlyTo reaching critical voltage VBAT, shown in current waveform such as Fig. 2 (a) of high-order Compound Topology rectification front and back.At this point, pattern switching is openedPass movement, the constant current compensation circuit of system are switched to constant-pressure compensation circuit, and circuit enters constant voltage output mode, output voltage VBAT,Constant voltage charging phase, cell voltage holding constant, electric current are gradually reduced, and when electric current is approximately 0, terminate charging, high-order is compoundShown in voltage waveform such as Fig. 2 (b) of topology rectification front and back.
Fig. 3 to Fig. 8 demonstrates the battery wireless charging of high-order combined type compensation network by taking high-order Compound Topology structure as an exampleThe validity of system.The loosely coupled transformer of use, coefficient of coup k are 0.2, primary side self-induction LPFor 380.2uH, secondary side self-induction LSFor 184.49uH, input voltage VINIt is 10A, constant-voltage charge electricity by theoretical calculation constant-current charge electric current for 330V, duty ratio D=1Pressure is 330V.If switching frequency is 85kHz, former and deputy side compensates inductance L1And L2Respectively 52.969uH and 50.085uH, it is former and deputySide compensating electric capacity CPAnd CSRespectively 66.188nF and 70nF, primary side additional capacitor C1For 10.714nF, the first, second secondary side is attachedC is held in power-up2And C3Respectively 26.085nF and 35nF.
Fig. 3 to Fig. 5 gives under high-order Compound Topology constant current mode, and battery equivalent impedance is respectively 15 Ω, 25 Ω and 33Driving signal v when Ωgate, bridge arm voltage vAB, input current iINWith output DC current IBATWaveform.It can from figureOut, when the equivalent resistance of battery changes to 33 Ω from 15 Ω, output electric current keeps 10A substantially, does not change with load.InputElectric current iINWith bridge arm voltage vABIt is substantially in phase, quadergy is effectively reduced, input current slightly lags behind bridge arm voltage, is convenient forSwitch mosfet pipe realizes zero voltage switch, reduces switching loss.
Fig. 6 to Fig. 8 gives under high-order Compound Topology constant voltage mode, and battery equivalent impedance is respectively 33 Ω, 70 Ω and 100Driving signal v when Ωgate, bridge arm voltage vAB, input current iINWith output DC voltage VBATWaveform.When on cell voltageWhen being raised to 330V, the charge mode of battery becomes constant-voltage charge from constant-current charge.It can be seen from the figure that the equivalent resistance of batteryWhen changing to 100 Ω from 33 Ω, output voltage is basically stable at 330V, has good constant-voltage characteristic.Input current iINAnd bridge armVoltage vABIt is substantially in phase, quadergy is effectively reduced, input current slightly lags behind bridge arm voltage, realizes convenient for switch mosfet pipeZero voltage switch reduces switching loss.