Disclosure of Invention
In view of the above drawbacks of the prior art, an object of the present invention is to provide a power supply circuit, a new energy control system and an energy coordination method, which are used for solving the problems of low battery life, low system efficiency, poor bus voltage stability, poor system reliability and the like in the prior art.
To achieve the above and other related objects, the present invention provides a power supply circuit including at least:
the alternating current-to-direct current module receives an alternating current power supply, converts the voltage of the alternating current power supply into bus voltage and provides the bus voltage for a direct current bus;
the N groups of new energy supply modules are respectively connected with the direct current buses, generate electric energy based on new energy and supply energy for the direct current buses; n is an integer greater than or equal to 1;
Each new energy supply module comprises a new energy power generation device, a new energy control unit, an energy storage battery and a bidirectional direct current-to-direct current unit; the new energy power generation device generates electric energy based on new energy; the first end of the new energy control unit is connected with the output end of the new energy power generation device and controls the new energy power generation device to convert electric energy for output; the energy storage battery is connected with the second end of the new energy control unit and is used for storing electric energy; one end of the bidirectional direct current-to-direct current unit is connected with the second end of the new energy control unit, and the other end of the bidirectional direct current-to-direct current unit is connected with the direct current bus and used for realizing bidirectional energy conversion between the energy storage battery and the direct current bus.
Optionally, when the ac power source works normally, the bus voltage is a first voltage value; when the alternating current power supply cannot work normally, the bus voltage is a second voltage value; the first voltage value is greater than the second voltage value.
More optionally, the first voltage value is equal to a maximum normal output voltage of the ac-dc module.
To achieve the above and other related objects, the present invention also provides a new energy control system, which at least includes:
the power supply circuit is used for providing bus voltage for the new energy control system;
The load module is connected with a direct current bus and acquires electric energy from the direct current bus;
and the comprehensive energy controller is communicated with the power supply circuit and the load module and is used for controlling the new energy control system to work.
Optionally, the load module includes a first load, a second load, and a third load; the first load and the second load work intermittently, and the third load works uninterruptedly.
More optionally, the integrated energy controller includes a communication interface, a sampling module and a control module; the communication interface is communicated with the alternating current-to-direct current module, the new energy control unit, the bidirectional direct current-to-direct current unit and the upper computer; the sampling module samples an alternating current power supply and a load; the control module is connected with the communication interface and the sampling module, and generates control signals of the alternating current-to-direct current module, the new energy control unit and the bidirectional direct current-to-direct current unit based on output signals of the sampling module and the communication interface.
More optionally, the integrated energy controller is in communication with the ac-dc conversion module, the new energy control unit and the host computer through an RS485 bus, and the integrated energy controller is in communication with the bidirectional dc-dc conversion unit through a CAN bus.
To achieve the above and other related objects, the present invention also provides an energy coordination method, which is implemented based on the new energy control system, and the energy coordination method at least includes:
the new energy control unit converts electric energy generated by the new energy power generation device, charges the energy storage battery with the generated electric energy, and determines a working mode according to the residual electric quantity of the energy storage battery;
When the alternating current power supply supplies power normally, the comprehensive energy controller controls the bidirectional direct current-to-direct current unit to perform bidirectional energy conversion on the energy storage battery and the direct current bus according to the residual electric quantity of the energy storage battery, at the moment, the bus voltage is controlled to be a first voltage value based on the alternating current-to-direct current module, and the alternating current-to-direct current module and the new energy supply module supply power for the load module together;
when the alternating current power supply cannot normally supply power, the comprehensive energy controller controls the bidirectional direct current-to-direct current unit to provide electric energy for the direct current bus according to the residual electric quantity of the energy storage battery, and at the moment, the bus voltage is controlled to be a second voltage value based on the new energy supply module;
Wherein the first voltage value is greater than the second voltage value.
Optionally, the energy coordination method further comprises: when the residual electric quantity of the energy storage battery is smaller than a first set value, the new energy control unit works in a maximum power point tracking mode; when the residual electric quantity of the energy storage battery is larger than a second set value, the new energy control unit enters an equalizing charge mode or a floating charge mode; the second set value is larger than or equal to the first set value.
More optionally, when the ac power is provided by the ac power grid, the new energy supply module preferentially supplies power to the dc bus in a peak period of normal power supply of the ac power grid, and the residual electric energy is provided by the ac power grid; and in a valley period of normal power supply of the alternating current power grid, the alternating current power grid supplies power for the direct current bus, and electric energy provided by the alternating current power grid is stored in the energy storage battery.
More optionally, the load module includes a first load, a second load, and a third load, where power consumption of the first load, the second load, and the third load decreases in sequence; when an alternating current power supply provided by an alternating current power grid cannot work normally, and an alternating current power supply is provided by a generator, the generator and the new energy supply module supply power for a working load, and the bus voltage is the first voltage value; when the alternating current power supply provided by the alternating current power grid cannot work normally and the generator does not provide the alternating current power supply, the new energy supply module supplies power for a working load, and the bus voltage is the second voltage value.
More optionally, when the first load, the second load and the third load are all operated, or the first load is turned off, the second load and the third load are operated, the method for supplying power to the generator and the new energy supply module includes:
when the generator provides an alternating current power supply, the alternating current-to-direct current module converts the alternating current power supply provided by the generator into bus voltage, and meanwhile, the new energy supply module provides the electric energy generated by the new energy power generation device for the direct current bus;
After the electric energy provided by the generator is exhausted, the new energy supply module provides the electric energy generated by the new energy power generation device for the direct current bus; if the new energy power generation device stops working, the new energy supply module supplies the electric energy in the energy storage battery to the direct current bus; and when the residual electric quantity in the energy storage battery is smaller than a preset value, the comprehensive energy controller sends out an alarm signal for supplying fuel to the generator.
More optionally, when the first load and the second load are turned off and the third load is operated, if the generator does not provide ac power, the bidirectional dc-dc conversion unit controls the bus voltage to be stabilized at a fixed value.
More optionally, when the first load and the second load are turned off and the third load is operated, if the generator does not provide an ac power source, the bidirectional dc-dc conversion unit is shorted, the energy storage battery is directly incorporated on the dc bus, and at this time, the bus voltage is determined by the voltage of the energy storage battery.
More optionally, when the first load and the second load are turned off and the third load is operated, the method for supplying power to the third load by the generator and the new energy supply module includes:
when the new energy power generation device works normally, the new energy supply module supplies electric energy generated by the new energy power generation device to the direct current bus;
If the new energy power generation device stops working, the new energy supply module supplies the electric energy in the energy storage battery to the direct current bus, and starts the generator when the residual electric quantity of the energy storage battery is smaller than a third set value, and the generator supplies power for the direct current bus and charges the energy storage battery;
If the energy storage battery is charged to a state that the residual electric quantity is larger than a fourth set value, the generator stops working, and the new energy power generation device still supplies power for the direct current bus;
Wherein the fourth set value is greater than the third set value.
As described above, the power supply circuit, the new energy control system and the energy coordination method of the present invention have the following beneficial effects:
1. when the power supply circuit and the new energy control system are operated in an island, the balance of the residual electric quantity of the energy storage battery is not required to be achieved by mutual charge and discharge among the new energy supply modules, and circulation current does not exist among the new energy supply modules, so that the service life of the battery is long, and the system efficiency is high.
2. The power supply circuit and the new energy source control system are characterized in that a new energy source power generation device is connected to a direct current bus through two stages of DCDC, and when the island operates, a first stage is used for controlling the new energy source power generation device to output maximum power, and a second stage is used for stabilizing output, so that the stability of bus voltage is ensured, and the system efficiency is further improved.
3. According to the power supply circuit and the new energy control system, the new energy power generation device and the new energy control unit are connected to the direct current bus after passing through the bidirectional direct current-to-direct current unit, so that the risk that lightning is directly connected into the direct current bus through the new energy power generation device and the new energy control unit can be greatly reduced; and the situation that the whole system is broken down due to the fact that any device incorporating a direct current bus is short-circuited is effectively avoided through the framework of the two-stage DCDC, and the system stability is high.
4. According to the energy coordination method, energy is coordinated according to different working conditions to realize power supply to a load; when the load power consumption is large, an alternating current power supply is taken as a main source and a new energy source is taken as an auxiliary source; when the load power consumption is small, the new energy is taken as a main source and the alternating current power supply is taken as an auxiliary source; the new energy is utilized to the greatest extent, the carbon emission is reduced, and the system efficiency is greatly improved.
Detailed Description
Other advantages and effects of the present invention will become apparent to those skilled in the art from the following disclosure, which describes the embodiments of the present invention with reference to specific examples. The invention may be practiced or carried out in other embodiments that depart from the specific details, and the details of the present description may be modified or varied from the spirit and scope of the present invention.
Please refer to fig. 2-4. It should be noted that, the illustrations provided in the present embodiment merely illustrate the basic concept of the present invention by way of illustration, and only the components related to the present invention are shown in the drawings and are not drawn according to the number, shape and size of the components in actual implementation, and the form, number and proportion of the components in actual implementation may be arbitrarily changed, and the layout of the components may be more complex.
Example 1
As shown in fig. 2, the present embodiment provides a power supply circuit 1, the power supply circuit 1 including:
the alternating current-direct current conversion module 11 and N groups of new energy supply modules 12, wherein N is an integer greater than or equal to 1.
As shown in fig. 2, the AC-to-dc module 11 receives an AC power AC and converts the voltage of the AC power AC into a BUS voltage Vbus and provides the BUS voltage Vbus to a dc BUS.
Specifically, the input end of the alternating current-to-direct current module 11 is connected with the alternating current power supply AC, and the output end is connected with the direct current BUS for converting alternating current into direct current; any circuit structure capable of converting alternating current into direct current is suitable for the present invention, and is not described here in detail. The AC power source AC includes, but is not limited to, an AC power grid and a generator (for example, the generator is a diesel generator), which may be an AC power grid, a generator, or a hybrid AC power supply device formed by the AC power grid and the generator, and any device capable of providing an AC voltage is suitable, which is not limited to this embodiment.
As shown in fig. 2, the new energy supply module 12 is connected to the dc BUS, generates electric energy based on new energy and supplies the dc BUS with energy.
Specifically, in the present embodiment, the number of the new energy supply modules 12 is set to 4 groups, and in actual use, the new energy supply modules may be set as needed, which is not limited to the present embodiment.
Specifically, the new energy supply module 12 includes a new energy generating device 121, a new energy control unit 122, an energy storage battery 123, and a bidirectional dc-dc conversion unit 124. The new energy power generation device 121 generates electric energy based on new energy, and the new energy power generation device 121 includes, but is not limited to, a solar cell and/or a wind power generation device. A first end of the new energy control unit 122 is connected to an output end of the new energy generating device 121, and controls the new energy generating device 121 to convert electric energy to output; as an example, the new energy control unit 122 is a maximum power point tracker (MPPT, maximum Power Point Tracking), and a new energy access terminal of the maximum power point tracker is connected to the new energy power generation device 121. The energy storage battery 123 is connected to the second end of the new energy control unit 122, and is used for storing electric energy; as an example, the positive electrode of the energy storage battery 123 is connected to the positive electrode of the battery output terminal of the maximum power point tracker, and the negative electrode is connected to the negative electrode of the battery output terminal of the maximum power point tracker. One end of the bidirectional direct current-to-direct current unit 124 is connected to the second end of the new energy control unit 122, and the other end is connected to the direct current BUS, so as to realize bidirectional energy conversion between the energy storage battery 123 and the direct current BUS; as an example, the positive electrode of the battery input/output end of the bidirectional dc-dc conversion unit 124 is connected to the positive electrode of the energy storage battery 123, the negative electrode of the battery input/output end is connected to the negative electrode of the energy storage battery 123, the positive electrode of the BUS input/output end is connected to the positive electrode of the dc BUS, and the negative electrode of the BUS input/output end is connected to the negative electrode of the dc BUS.
It should be noted that, the maximum power point tracker further includes a load connection port, and in this embodiment, the load connection port is suspended.
As shown in fig. 2, when the AC power supply AC works normally, the AC-dc conversion module 11 is used as a voltage source to control the BUS voltage Vbus on the dc BUS, so that the BUS voltage Vbus is a first voltage value, and the first voltage value is equal to the maximum normal output voltage of the AC-dc conversion module 11; the maximum normal output voltage is the maximum value of the ac-dc conversion module 11 in a settable output voltage range. At this time, the bidirectional dc to dc unit 124 operates as a current source. When the AC power supply AC cannot work normally (the voltage provided by the AC-dc conversion module 11 is less than the threshold value), at least one of the bidirectional dc-dc conversion units 124 is used as a voltage source to control the BUS voltage Vbus on the dc BUS, so that the BUS voltage Vbus is a second voltage value. The first voltage value is larger than the second voltage value, the first voltage value is a fixed value, and the second voltage value is a fixed value or a non-fixed value; as an example, the first voltage value is set to 57V, the second voltage value is set to 51V, and the threshold value is set to 48V; in practical use, each numerical value can be set according to the need, and the present embodiment is not limited to the above.
In the power supply circuit, one end of the bidirectional direct current-to-direct current unit is connected with the new energy control unit and is simultaneously connected with the energy storage battery, and the other end of the bidirectional direct current-to-direct current unit is connected with the direct current bus. When the island operates, the bidirectional direct current-to-direct current unit can work in different states according to the condition of the residual electric quantity of the battery and the requirement of a load; the new energy power generation device always supplements energy for the energy storage battery through the new energy control unit so as to improve the residual capacity of the energy storage battery, so that the new energy supply modules of each group do not need to be charged and discharged to balance the residual capacity of the energy storage battery, and therefore, circulation does not exist among the new energy supply modules of each group, circulation does not exist among the energy storage batteries, and the service life of the battery and the system efficiency are greatly improved; the new energy power generation device is connected to the direct current bus through the two-stage DCDC (new energy control unit and the bidirectional direct current-to-direct current unit), and when the island operates, the first stage (new energy control unit) is used for controlling the new energy power generation device to output with maximum power, and the second stage (bidirectional direct current-to-direct current unit) is used for stabilizing output, so that the stability of the bus voltage is ensured, and the system efficiency is further improved; according to the novel energy power generation device and the novel energy control unit, the novel energy power generation device and the novel energy control unit are not directly connected to the direct current bus, but pass through the bidirectional direct current-to-direct current unit, so that the risk that lightning directly accesses the direct current bus through the novel energy power generation device and the novel energy control unit is greatly reduced, the risk that the whole direct current bus is broken down due to short circuit failure of the novel energy control unit is avoided, and the system stability is improved.
Example two
As shown in fig. 3, the present embodiment provides a new energy control system, which includes:
a power supply circuit 1, a load module 2 and a comprehensive energy controller 3.
As shown in fig. 3, the power supply circuit 1 is configured to provide a bus voltage Vbus to the new energy control system.
Specifically, the power circuit 1 adopts the power circuit structure of the first embodiment, and the specific connection relationship and principle of the devices are referred to the first embodiment, which is not described herein in detail.
As shown in fig. 3, the load module 2 is connected to a dc BUS, and obtains electric energy from the dc BUS.
Specifically, in the present embodiment, the load module 2 includes a first load 21, a second load 22, and a third load 23; wherein, the first load 21 and the second load 22 work intermittently, and the third load 23 works continuously. As an example, the first load 21 is a 5G communication device, and the second load 22 is a 4G communication device, for satisfying the requirements of integrated services (4G, 5G communication and providing signals for 4K live broadcast); when the power supplied from the power supply circuit 1 is insufficient, the first load 21 and the second load 22 may be turned off. As an example, the third load 23 is a monitoring device, including but not limited to a camera or other sensors, for meeting the requirements of two-wing services (including water service detection, river management, yangtze river banning, bridge anti-collision, etc.), and the third load 23 needs to keep a working state all weather; in this example, the third load 23 further comprises an inverter (not shown in the figures) for converting the bus voltage Vbus into an alternating current for powering the monitoring device.
It should be noted that, in actual use, the number and type of the loads may be selected according to the needs, which is not limited to the present embodiment.
As shown in fig. 3, the integrated energy controller 3 communicates with the power circuit 1 and the load module 2, and is configured to control the new energy control system to work.
Specifically, as shown in fig. 4, in the present embodiment, the integrated energy controller 3 includes a communication interface 31, a sampling module 32, and a control module 33. The communication interface 31 communicates with the ac-dc conversion module 11, the new energy control unit 122, the bidirectional dc-dc conversion unit 124, and an upper computer (not shown in the figure, which may be disposed at a remote end or in the new energy control system) to obtain working data of the ac-dc conversion module 11, the new energy control unit 122, and the bidirectional dc-dc conversion unit 124, receive an instruction sent by the upper computer, and feed back the data to the upper computer. The sampling module 32 samples the AC power AC and the load module 2 to obtain a voltage sampling signal of the AC power AC and a current sampling signal of a load end. The control module 33 is connected to the communication interface 31 and the sampling module 32, and generates control signals of the ac-dc conversion module 11, the new energy control unit 122 and the bidirectional dc-dc conversion unit 124 based on output signals of the sampling module 32 and the communication interface 31. In practical use, the functional modules in the integrated energy controller 3 may be set as required, which is not limited to the embodiment.
More specifically, as an example, the integrated energy controller 3 communicates with the ac-dc conversion module 11, the new energy control unit 122, and the host computer through an RS485 bus, and the integrated energy controller 3 communicates with the bidirectional dc-dc conversion unit 124 through a CAN bus.
Example III
The present embodiment provides an energy coordination method, implemented based on the new energy control system of the second embodiment, where the energy coordination method includes:
① The new energy control unit 122 converts the electric energy generated by the new energy power generation device 121, charges the energy storage battery 123 with the generated electric energy, and determines the operation mode of the new energy control unit 122 according to the remaining power of the energy storage battery 123.
Specifically, when the remaining power of the energy storage battery 123 is smaller than the first set value, the new energy control unit 122 operates in the maximum power point tracking mode; when the remaining power of the energy storage battery 123 is greater than a second set value, the new energy control unit 122 enters an equalizing charge mode or a floating charge mode; the second set value is larger than or equal to the first set value. As an example, the first set point is 90% of the energy storage battery capacity, and the second set point is 95% of the energy storage battery capacity; the first setting value and the second setting value can be set according to the requirement in actual use.
It should be noted that the remaining power of the energy storage battery 123 may be obtained based on the SOC of the energy storage battery or the voltage of the energy storage battery, which are not described in detail herein.
② When the AC power supply AC supplies power normally, the integrated energy controller 3 controls the bidirectional dc-dc conversion unit 124 to perform bidirectional energy conversion on the energy storage battery 123 and the dc BUS according to the remaining power of the energy storage battery 123, and at this time, the BUS voltage Vbus is controlled to be a first voltage value based on the AC-dc conversion module 11, and the AC-dc conversion module 11 and the new energy supply module 12 supply power to the load module together.
In particular, the alternating current power source AC is provided by an alternating current grid or generator. When the AC power source AC supplies power normally, the AC-dc conversion module 11 as a voltage source stabilizes the bus voltage Vbus at a first voltage value, which is set to 57V as an example. At this time, the bidirectional dc to dc unit 124 operates as a current source.
Specifically, the integrated energy controller 3 controls the bidirectional dc to dc unit 124 to feed energy from the energy storage battery 123 to the dc BUS according to the remaining power of the energy storage battery 123, or controls the bidirectional dc to dc unit 124 to feed energy from the dc BUS to the energy storage battery 123. The amount of the feeding energy depends on the remaining amount of the energy storage battery 123, and when the energy storage battery 123 feeds the energy to the dc BUS, the remaining amount of the energy is proportional to the feeding energy, and when the dc BUS feeds the energy to the energy storage battery 123, the remaining amount of the energy is inversely proportional to the feeding energy.
③ When the AC power supply AC fails to supply power normally, the integrated energy controller 3 controls the bidirectional dc-dc converting unit 124 to supply power to the dc BUS according to the remaining power of the energy storage battery 123, and then controls the BUS voltage Vbus to be a second voltage value based on the new energy supply module 12; the first voltage value is greater than the second voltage value.
Specifically, as an example, when the AC power source AC is disconnected or the voltage output by the AC-dc conversion module 11 is smaller than a threshold value, the AC power source AC is considered to be unable to operate normally, at this time, at least one of the N bidirectional dc-dc conversion units 124 is used as a voltage source to control the BUS voltage Vbus on the dc BUS, so that the BUS voltage Vbus is a second voltage value. At this time, the second voltage value is a stable fixed value, and as an example, the second voltage value is set to 51V; the threshold value is set to 48V as an example of the second voltage value when the threshold value is smaller than a fixed value.
Specifically, as another example, when the AC power source AC is disconnected or the voltage output by the AC-dc conversion module 11 is smaller than a threshold value, the AC power source AC is considered to be unable to operate normally, at this time, the N bidirectional dc-dc conversion units 124 are shorted by an internal power switch tube or an external relay, the energy storage battery 123 is directly incorporated into the dc BUS, and at this time, the BUS voltage Vbus is determined by the voltage of the energy storage battery 123, that is, the second voltage value is a variable value.
The invention divides the new energy control system into three working conditions, and carries out corresponding energy coordination based on the three working conditions, and the specific energy coordination method is as follows. As an example, the load module 2 includes a first load 21, a second load 22, and a third load 23, wherein power consumption of the first load 21, the second load 22, and the third load 23 decreases in sequence.
Working condition one: the alternating current power source AC is provided by an alternating current power grid, and the alternating current power grid and the new energy supply module 12 jointly supply power to the load module 2.
Specifically, the alternating current power supply AC supplies power normally, and the power is sufficient at this time, and in this embodiment, the first load 21, the second load 22, and the third load 23 all operate; in practical use, the partial load may be shut down as required, which is not limited to the present embodiment. The ac-dc module 11 is used as a voltage source to control the bus voltage Vbus to be a first voltage value, and each bidirectional dc-dc converting unit 124 is used as a current source.
Specifically, as another implementation manner of the present invention, the integrated energy controller 3 further controls the bidirectional dc to dc converter unit 124 to charge and discharge the energy storage battery 123 based on the demand side. In the peak period of normal power supply of the alternating current power grid, the new energy supply module 12 supplies power to the direct current BUS BUS preferentially, and the residual electric energy is supplied by the alternating current power grid; during the off-peak period of normal power supply of the ac power grid, the ac power grid supplies power to the dc BUS, and the electric energy provided by the ac power grid is stored in the energy storage battery 123.
Working condition II: the AC power grid is not powered, the AC power source AC is provided by a generator, and the generator can timely supply fuel, and at this time, the generator and the new energy supply module 12 supply power to the working load. When the generator provides an Alternating Current (AC), the generator and the new energy supply module 12 supply power to the working load, and the bus voltage Vbus is the first voltage value; at this time, the generator operates normally, the ac-dc conversion module 11 operates as a voltage source, and each bidirectional dc-dc conversion unit 124 operates as a current source. When the generator does not provide an Alternating Current (AC), the new energy supply module 12 supplies power to the working load, and the bus voltage Vbus is the second voltage value; at this time, at least one of the bidirectional dc to dc units 124 operates as a voltage source, and the other bidirectional dc to dc units operate as a current source.
Specifically, in the present embodiment, the first load 21, the second load 22, and the third load 23 are all operated, or the first load 21 is turned off, the second load, and the third load are operated; the operating state of each load can be determined according to the electric energy condition.
Specifically, the method for supplying power to the generator and the new energy supply module 12 includes:
When the generator works normally, the alternating current-to-direct current module 11 converts an alternating current power supply AC provided by the generator into a bus voltage Vbus, wherein the bus voltage Vbus is the first voltage value; simultaneously, the new energy supply module 12 supplies the electric energy generated by the new energy generating device 121 to the direct current BUS;
After the electric energy provided by the generator is exhausted, the new energy supply module 12 provides the electric energy generated by the new energy generating device 121 to the dc BUS; if the new energy power generation device 121 stops working, the new energy supply module 12 provides the electric energy in the energy storage battery 123 to the dc BUS; when the remaining power in the energy storage battery 123 is smaller than a preset value, the integrated energy controller 3 sends out an alarm signal for supplying the fuel to the generator. The preset value can be set according to actual needs, and is not limited herein.
It should be noted that, after the generator is refueled, the generator still works normally; the generator is used as a main body for supplying power, and the new energy supply module 12 is used as a supplement for electric energy.
And (3) working condition III: the AC power grid is not powered, the AC power source AC is provided by a generator but the generator is not timely refueled, at which point the generator and the new energy supply module 12 supply power to the operating load. When the generator does not provide an Alternating Current (AC), the new energy supply module 12 works normally and supplies power to the working load, and the bus voltage Vbus is the second voltage value; at this time, at least one of the bidirectional dc to dc units 124 operates as a voltage source, and the other bidirectional dc to dc units operate as a current source. When the generator provides an Alternating Current (AC), the generator and the new energy supply module 12 supply power to an operating load, and the bus voltage Vbus is the first voltage value; at this time, the generator operates normally, the ac-dc conversion module 11 operates as a voltage source, and each bidirectional dc-dc conversion unit 124 operates as a current source.
Specifically, due to the insufficient electric energy, the intermittently operable loads are turned off, and in this embodiment, the first load and the second load are turned off, and the third load is operated.
Specifically, as an example, if the generator does not provide the alternating current power AC, the bidirectional direct current to direct current unit 124 controls the bus voltage Vbus to be stabilized at a fixed value (second voltage value). As another example, if the generator does not provide an AC power source AC, the dc-dc unit 124 is shorted, the energy storage battery 123 is directly connected to the dc BUS, and the BUS voltage Vbus is determined by the voltage of the energy storage battery 123 (the second voltage value is not a fixed value).
Specifically, the method for supplying power to the third load by the generator and the new energy supply module 12 includes:
When the new energy power generation device 121 works normally, the new energy supply module 12 provides the electric energy generated by the new energy power generation device 121 to the dc BUS;
If the new energy power generation device 121 stops working (for example, solar energy cannot be obtained in rainy days and wind power is small, so that the new energy power generation device stops working), the new energy supply module 12 provides the electric energy in the energy storage battery 123 to the direct current BUS, and starts the generator when the residual electric quantity of the energy storage battery 123 is smaller than a third set value, and the generator supplies power to the direct current BUS and charges the energy storage battery 123;
if the remaining power of the energy storage battery 123 is greater than the fourth set value, the generator stops working, and the new energy power generation device 121 still supplies power to the dc BUS;
Wherein the fourth set value is greater than the third set value. As an example, the third set point is 60% of the energy storage battery capacity, and the fourth set point is 90% of the energy storage battery capacity; in practical use, specific values may be set according to the needs, and are not limited to the present embodiment.
It should be noted that, when the new energy power generation device 121 resumes normal operation, the power generator stops operating; the new energy power generation device 121 is used as a main body for supplying power, and the generator is used as a supplement of electric energy.
In summary, the present invention provides a power circuit, a new energy control system and an energy coordination method, including: the alternating current-to-direct current module receives an alternating current power supply, converts the voltage of the alternating current power supply into bus voltage and provides the bus voltage for a direct current bus; the N groups of new energy supply modules are respectively connected with the direct current buses, generate electric energy based on new energy and supply energy for the direct current buses; n is an integer greater than or equal to 1; each new energy supply module comprises a new energy power generation device, a new energy control unit, an energy storage battery and a bidirectional direct current-to-direct current unit; the new energy power generation device generates electric energy based on new energy; one end of the new energy control unit is connected with the output end of the new energy power generation device and controls the new energy power generation device to convert electric energy for output; the energy storage battery is connected with the other end of the new energy control unit and is used for storing electric energy; one end of the bidirectional direct current-to-direct current unit is connected with the output end of the new energy control unit, and the other end of the bidirectional direct current-to-direct current unit is connected with the direct current bus and used for realizing bidirectional energy conversion between the energy storage battery and the direct current bus. The power supply circuit, the new energy control system and the energy coordination method have no circulation current during island operation, long service life of the battery and high system efficiency; the new energy power generation device is connected to the direct current bus through two stages of DCDC, and when the island operates, the first stage is used for controlling the new energy power generation device to output the maximum power, and the second stage is used for stabilizing the output, so that the stability of the bus voltage is ensured, and the system efficiency is further improved; compared with the prior art, the number of devices which are integrated with the direct current bus is greatly reduced, the situation that the whole system is broken down due to the fact that any one device which is integrated with the direct current bus is short-circuited is effectively avoided through the framework of the two-stage DCDC, and the system stability is high. Therefore, the invention effectively overcomes various defects in the prior art and has high industrial utilization value.
The above embodiments are merely illustrative of the principles of the present invention and its effectiveness, and are not intended to limit the invention. Modifications and variations may be made to the above-described embodiments by those skilled in the art without departing from the spirit and scope of the invention. Accordingly, it is intended that all equivalent modifications and variations of the invention be covered by the claims, which are within the ordinary skill of the art, be within the spirit and scope of the present disclosure.