Power station-based control method and device, electronic device and storage medium

Abstract

The application discloses a control method and device based on a power station, electronic equipment and a storage medium. The control method comprises the following steps: in a normal operation mode, a power transformer is used to supply power to an AC bus, and an electronic transformer is used as a backup power supply of the AC bus; in the normal operation mode, power balance of a first power supply and a second power supply of a DC bus is controlled; in the case that active power flowing to a high-voltage side on a low-voltage outgoing line total switch of the power transformer and / or active power is greater than a preset reverse power limit value, reverse power operation is controlled. The application solves the technical problem that the stability and safety of continuous power supply operation of a power station cannot be ensured in the related art.

Description

Technical Field

[0001] This invention relates to the field of power plant control technology, and more specifically, to a power plant-based control method and apparatus, electronic equipment, and storage medium. Background Technology

[0002] In recent years, with the development of new energy technologies and related power technologies, extensive research has been conducted on integrated charging, discharging, and energy storage power stations. The construction and operation of such stations is a complex systems engineering project, involving multiple disciplines such as power systems, power electronics, information and communication, economics, and structural design, with some overlap between these disciplines. Among the related technologies, integrated charging, discharging, and energy storage power stations suffer from low energy conversion rates in power regulation, and the inability to guarantee the stability and safety of continuous power supply operation during the control process. Furthermore, they have limited control functions and high operating costs.

[0003] There is currently no effective solution to the above problems. Summary of the Invention

[0004] This invention provides a power plant-based control method and apparatus, electronic device and storage medium, to at least solve the technical problem in the related art that the stability and safety of continuous power supply operation of a power plant cannot be guaranteed.

[0005] According to one aspect of the present invention, a power plant-based control method is provided, comprising: in a normal operating mode, using a power transformer to supply power to an AC bus and using an electronic transformer as a backup power source for the AC bus, wherein the normal operating mode refers to a mode in which both the power transformer and the electronic transformer are operating normally; in the normal operating mode, controlling the power balance of a first power source and a second power source of the DC bus; and controlling reverse power operation when the active power at the low-voltage outgoing main switch of the power transformer flows to the high-voltage side, and / or, if the active power is greater than a preset reverse power limit.

[0006] Optionally, after using a power transformer to supply power to the AC bus and an electronic transformer as a backup power source for the AC bus, the method further includes: based on the voltage information of the power transformer, using a central controller to determine whether the power transformer has malfunctioned, and detecting whether there is a change-of-position alarm information for the DC circuit breaker's open-circuit signal; if no change-of-position alarm information is detected, re-tripping the DC circuit breaker; if the power transformer malfunctions, controlling the AC / DC converter to shut down; if an abnormal voltage is detected at the switching switch of the AC dual power supply, controlling the switching switch to switch; if an abnormal voltage is detected at the converter energy storage device of the AC energy storage system, controlling the AC voltage source mode to switch to off-grid mode operation; if a voltage is detected at the input of the controllable switch of the converter energy storage device, controlling the controllable switch to close, and changing the power supply terminal of the AC bus to the electronic transformer.

[0007] Optionally, after controlling the controllable switch to close and changing the power supply terminal of the AC bus to the electronic transformer, the method further includes: determining whether the power transformer is supplying power normally; if the power transformer is supplying power normally, controlling the switching switch to switch to a preset circuit; and after the switching switch is switched to the preset circuit, controlling the converter energy storage device to switch to grid-connected operation.

[0008] Optionally, after using a power transformer to supply power to the AC bus and using an electronic transformer as a backup power source for the AC bus, the method further includes: using a central controller to determine whether the electronic transformer has malfunctioned based on the signal information of the electronic transformer; and controlling the electronic transformer to shut down in the event of a malfunction.

[0009] Optionally, after controlling the electronic transformer to shut down, the method further includes: determining whether the electronic transformer is powered normally; and if the electronic transformer is powered normally, issuing a one-key start command to control the electronic transformer to start grid connection, wherein the one-key start command includes at least one of the following: one-key start command for electronic transformer, one-key start command for AC DC generator, and one-key start command for DC energy storage device.

[0010] Optionally, the step of controlling the power balancing of the first and second power supplies of the DC bus includes: when both the electronic transformer and the preset converter are operating in voltage droop mode, controlling the microgrid system controller to coordinate the power between the voltage source of the electronic transformer and the voltage source of the preset converter; when the output power difference between the electronic transformer and the preset converter is greater than a preset threshold, performing power balancing control; representing the average output power of the electronic transformer and the preset converter as the current output target power; when the current power of the electronic transformer is not equal to the target power, changing the droop coefficient of the electronic transformer and changing the droop coefficient of the preset converter, so as to complete the power balancing control of the first and second power supplies of the DC bus.

[0011] Optionally, before balancing the power of the first and second power supplies of the DC bus, the method further includes: using the voltage information of the power transformer, using the central controller to determine whether the second power supply has a fault, and detecting whether there is a change alarm information of the DC circuit breaker tripping input signal; if no change alarm information is detected, re-tripping the DC circuit breaker; and controlling the AC / DC converter to shut down if the second power supply has a fault.

[0012] Optionally, before controlling the power balancing of the first and second power supplies of the DC bus, the method further includes: using a central controller to determine whether the first power supply has failed based on the signal information of the electronic transformer; and controlling the electronic transformer to shut down if the electronic transformer fails.

[0013] Optionally, when the active power at the low-voltage outgoing main switch of the power transformer flows to the high-voltage side, and / or when the active power exceeds a preset reverse power limit, the step of controlling reverse power operation includes: when the DC energy storage device is discharging, reducing the discharge power of the DC energy storage device according to a first preset threshold; when the DC energy storage device is charging, increasing the charging power of the DC energy storage device according to a second preset threshold; when the power of the DC energy storage device cannot be controlled and / or the reverse power cannot be eliminated after control, controlling the power adjustment of the AC energy storage device; and when the reverse power cannot be eliminated after controlling the power of the DC energy storage device and controlling the AC energy storage device, controlling the power generation of the photovoltaic system.

[0014] Optionally, it also includes: in the normal operating mode, controlling the charging and discharging of the energy storage.

[0015] Optionally, in the normal operating mode, the steps for controlling the charging and discharging of energy storage include: when charging the AC energy storage device, determining that the maximum charging power of the AC energy storage device is less than or equal to the maximum allowable charging power given by the AC energy storage device; when discharging the AC energy storage device, selecting the minimum power between the maximum allowable discharge power given by the AC energy storage device and the AC load power as the maximum discharge power of the AC energy storage device; when charging the DC energy storage device, calculating the difference between the photovoltaic power generation power and the current DC charging load to obtain an initial power; adding a preset power value to the initial power to obtain a target power; selecting the minimum power between the target power and the maximum allowable charging power given by the DC energy storage device as the maximum charging power of the DC energy storage device; and when discharging the DC energy storage device, calculating the difference between the DC load power and the photovoltaic power generation power, and selecting the minimum power between the maximum allowable discharge power given by the DC energy storage device and the difference as the maximum discharge power of the DC energy storage device.

[0016] According to another aspect of the present invention, a power plant-based control device is also provided, comprising: a power supply unit, configured to supply power to an AC bus using a power transformer and to use an electronic transformer as a backup power source for the AC bus in a normal operating mode, wherein the normal operating mode refers to a mode in which both the power transformer and the electronic transformer are operating normally; a first control unit, configured to control the power balancing of a first power source and a second power source of the DC bus in the normal operating mode; and a second control unit, configured to control reverse power operation when the active power at the low-voltage outgoing main switch of the power transformer flows to the high-voltage side, and / or when the active power is greater than a preset reverse power limit.

[0017] Optionally, the control device further includes: a first judgment module, used to determine whether the power transformer has malfunctioned based on the voltage information of the power transformer after the power transformer is used to supply power to the AC bus and the electronic transformer is used as the backup power source for the AC bus, and to detect whether there is a change alarm information of the DC circuit breaker tamper input signal; a first re-trip module, used to re-trip the DC circuit breaker if no change alarm information is detected; a first control module, used to control the AC-DC converter to shut down if the power transformer malfunctions; a second control module, used to control the switching switch to switch if the voltage of the AC dual power supply switching switch is detected to be abnormal; a third control module, used to control the AC voltage source mode to switch to off-grid mode operation if the voltage of the converter energy storage system is detected to be abnormal; and a fourth control module, used to control the controllable switch to close and change the power supply terminal of the AC bus to the electronic transformer if the input terminal of the controllable switch of the converter energy storage system is detected to have voltage.

[0018] Optionally, the control device further includes: a second judgment module, used to determine whether the power transformer is supplying power normally after controlling the controllable switch to close and changing the power supply terminal of the AC bus to the electronic transformer; a fifth control module, used to control the switching switch to switch to a preset circuit when the power transformer is supplying power normally; and a sixth control module, used to control the converter energy storage device to switch to grid-connected operation after the switching switch is switched to the preset circuit.

[0019] Optionally, the control device further includes: a third judgment module, used to determine whether the electronic transformer has malfunctioned based on the signal information of the electronic transformer after the power transformer is used to supply power to the AC bus and the electronic transformer is used as a backup power source for the AC bus; and a seventh control module, used to control the electronic transformer to shut down in the event of a malfunction.

[0020] Optionally, the control device further includes: a fourth judgment module, used to determine whether the electronic transformer is powered normally after controlling the electronic transformer to stop; and an eighth control module, used to issue a one-key start command to control the electronic transformer to start grid connection when the electronic transformer is powered normally, wherein the one-key start command includes at least one of the following: one-key start command for electronic transformer, one-key start command for AC DC generator, and one-key start command for DC energy storage device.

[0021] Optionally, the first control unit includes: a ninth control module, used to control the microgrid system controller to coordinate the power between the voltage source of the electronic transformer and the voltage source of the preset converter when both the electronic transformer and the preset converter are operating in voltage droop mode; a tenth control module, used to perform power balancing control when the output power difference between the electronic transformer and the preset converter is greater than a preset threshold; a first characterization module, used to characterize the average output power of the electronic transformer and the preset converter as the current output target power; and a first modification module, used to change the droop coefficient of the electronic transformer and the droop coefficient of the preset converter when the current power of the electronic transformer is not equal to the target power, so as to complete the power balancing control of the first power supply and the second power supply of the DC bus.

[0022] Optionally, the control device further includes: a fifth judgment module, used to determine, based on the voltage information of the power transformer, whether the second power supply has a fault, and to detect whether there is a change alarm information of the DC circuit breaker tamper input signal before the power of the first and second power supplies of the DC bus is balanced; a second re-trip module, used to re-trip the DC circuit breaker if no change alarm information is detected; and an eleventh control module, used to control the AC / DC converter to shut down when the second power supply has a fault.

[0023] Optionally, the control device further includes: a sixth judgment module, used to determine, based on the signal information of the electronic transformer, whether the first power supply has failed before controlling the power balancing of the first and second power supplies of the DC bus; and a twelfth control module, used to control the electronic transformer to shut down in the event of a failure.

[0024] Optionally, the second control unit includes: a first reduction module, configured to reduce the discharge power of the DC energy storage device according to a first preset threshold when the DC energy storage device is discharging; a first increase module, configured to increase the charging power of the DC energy storage device according to a second preset threshold when the DC energy storage device is charging; a thirteenth control module, configured to control the AC energy storage device to adjust its power when the power of the DC energy storage device cannot be controlled and / or the reverse power cannot be eliminated after control; and a fourteenth control module, configured to control the power generation of the photovoltaic system when the power of the DC energy storage device is controlled and the reverse power cannot be eliminated after the AC energy storage device is controlled.

[0025] Optionally, the control device further includes a fifteenth control module, used to control the charging and discharging of the energy storage in the normal operating mode.

[0026] Optionally, the fifteenth control module includes: a first determining submodule, configured to determine, when charging the AC energy storage device, that the maximum charging power of the AC energy storage device is less than or equal to the maximum allowable charging power given by the AC energy storage device; a first selecting submodule, configured to select, when discharging the AC energy storage device, the minimum power between the maximum allowable discharge power given by the AC energy storage device and the AC load power as the maximum discharge power of the AC energy storage device; a first calculating submodule, configured to calculate, when charging the DC energy storage device, the difference between the photovoltaic power generation power and the current DC charging load to obtain an initial power; a first increasing submodule, configured to increase the initial power by a preset power value to obtain a target power; a second selecting submodule, configured to select, when the target power and the maximum allowable charging power given by the DC energy storage device, the minimum power as the maximum charging power of the DC energy storage device; and a second calculating submodule, configured to, when discharging the DC energy storage device, calculate, when the DC load power and the photovoltaic power generation power are differing, and select, when the maximum allowable discharge power given by the DC energy storage device and the difference are differing, the minimum power as the maximum discharge power of the DC energy storage device.

[0027] According to another aspect of the present invention, an electronic device is also provided, comprising: a processor; and a memory for storing executable instructions of the processor; wherein the processor is configured to perform the above-described power plant-based control method by executing the executable instructions.

[0028] According to another aspect of the present invention, a computer-readable storage medium is also provided, the computer-readable storage medium including a stored computer program, wherein, when the computer program is executed, it controls the device where the computer-readable storage medium is located to perform the above-described power station-based control method.

[0029] In this disclosure, under normal operating mode, a power transformer is used to supply power to the AC bus, and an electronic transformer is used as a backup power source for the AC bus. Under normal operating mode, the power balance of the first and second power sources on the DC bus is controlled. When active power flows from the low-voltage main switch of the power transformer to the high-voltage side, and / or when the active power exceeds a preset reverse power limit, reverse power operation is controlled. In this application, when both the power transformer and the electronic transformer are operating normally, the power transformer can be used to supply power to the AC bus, and the electronic transformer can be used as a backup power source for the AC bus. Controlling the power balance of the two power sources on the DC bus and controlling reverse power operation ensures the stability and safety of continuous power supply operation of the power station during the control process. It also increases functional versatility, reduces operating costs, and thus solves the technical problem in related technologies that cannot guarantee the stability and safety of continuous power supply operation of the power station. Attached Figure Description

[0030] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0031] Figure 1 This is a flowchart of an optional power station-based control method according to an embodiment of the present invention;

[0032] Figure 2 This is a schematic diagram of an optional control system structure according to an embodiment of the present invention;

[0033] Figure 3 This is a schematic diagram of an optional coordination control device hardware architecture according to an embodiment of the present invention;

[0034] Figure 4 This is a schematic diagram of an optional power station-based control device according to an embodiment of the present invention. Detailed Implementation

[0035] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0036] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0037] The following embodiments of the present invention can be applied to various power station-based control systems / applications / equipment. The present invention provides a control method applicable to a 10 kV power generation, charging, storage, and discharging station system. The entire power station can be equipped with an energy coordination control system and a central controller to achieve interactive integration and flexible allocation of energy among AC / DC distribution networks, distributed energy generation, charging equipment, and energy storage systems. Furthermore, this control method integrates the advantages of electric vehicle charging stations and energy storage power stations, enabling bidirectional scheduling of battery energy and featuring diversified functions and reduced operating costs. A power regulation system (PCS) can be installed within the integrated charging, discharging, and storage power station. This system consists of multiple parallel PCS sub-modules, employing a hierarchical control structure. Based on the management and scheduling of the host computer, the PCS can operate in various operating modes.

[0038] The present invention will now be described in detail with reference to various embodiments.

[0039] Example 1

[0040] According to an embodiment of the present invention, a control method embodiment based on a power plant is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0041] Figure 1 This is a flowchart of an optional power station-based control method according to an embodiment of the present invention, such as... Figure 1 As shown, the method includes the following steps:

[0042] Step S101: In normal operation mode, a power transformer is used to supply power to the AC bus, and an electronic transformer is used as a backup power source for the AC bus. Normal operation mode refers to the mode in which both the power transformer and the electronic transformer are operating normally.

[0043] Step S102: In normal operation mode, control the power balance of the first and second power supplies of the DC bus.

[0044] Step S103: When the active power on the low-voltage outgoing main switch of the power transformer flows to the high-voltage side, and / or when the active power is greater than the preset reverse power limit, control the reverse power operation.

[0045] Through the above steps, in normal operating mode, a power transformer can be used to supply power to the AC bus, and an electronic transformer can be used as a backup power source for the AC bus. In normal operating mode, the power of the first and second power sources of the DC bus is balanced. When active power flows from the low-voltage main switch of the power transformer to the high-voltage side, and / or when the active power exceeds a preset reverse power limit, reverse power operation is controlled. In this embodiment of the invention, when both the power transformer and the electronic transformer are operating normally, the power transformer can be used to supply power to the AC bus, and the electronic transformer can be used as a backup power source for the AC bus. The power of the two power sources of the DC bus is balanced, and reverse power operation is controlled. This ensures the stability and safety of continuous power supply operation of the power station during the control process, increases functional versatility, reduces operating costs, and thus solves the technical problem in related technologies that cannot guarantee the stability and safety of continuous power supply operation of the power station.

[0046] The embodiments of the present invention will now be described in detail with reference to the steps described above.

[0047] Step S101: In normal operation mode, a power transformer is used to supply power to the AC bus, and an electronic transformer is used as a backup power source for the AC bus. Normal operation mode refers to the mode in which both the power transformer and the electronic transformer are operating normally.

[0048] In this embodiment of the invention, in normal operation mode (i.e., when both the power transformer (i.e., the box-type substation) and the electronic transformer (i.e., the portable power adapter) are operating normally), the 380V AC bus can be powered by the box-type substation (i.e., the second power source, referred to as II), and the portable power adapter (i.e., the first power source, referred to as I) can serve as a backup power source for the 380V AC bus (i.e., the power transformer is used to power the AC bus, and the electronic transformer is used as a backup power source for the AC bus). The PCS (also known as the converter energy storage device) of the AC energy storage system operates in P / Q source mode and receives system commands to perform power distribution.

[0049] Optionally, after using a power transformer to supply power to the AC bus and an electronic transformer as a backup power source for the AC bus, the system further includes: using a central controller based on the voltage information of the power transformer to determine whether the power transformer has malfunctioned and to detect whether there is a change-of-position alarm information for the DC circuit breaker's open position signal; re-tripping the DC circuit breaker if no change-of-position alarm information is detected; controlling the AC / DC converter to shut down if the power transformer malfunctions; controlling the switching switch to switch if an abnormal voltage is detected in the AC dual power supply switching switch; controlling the AC voltage source mode to switch to off-grid mode if an abnormal voltage is detected in the AC energy storage system's converter energy storage device; and controlling the controllable switch to close and changing the AC bus power supply to the electronic transformer if voltage is detected at the input of the controllable switch of the converter energy storage device.

[0050] In this embodiment of the invention, the central controller can make a II-channel fault judgment based on the three-phase voltage (whether there is a voltage loss) on the low-voltage side of the transformer (i.e., based on the voltage information of the power transformer, the central controller judges whether the power transformer has a fault). Simultaneously, it detects whether there is a DC circuit breaker trip signal change alarm information (i.e., detects whether there is a DC circuit breaker trip signal change alarm information). If no such trip signal change alarm information is found, the 750V side DC circuit breaker is re-tripped after a delay (i.e., the DC circuit breaker is re-tripped even if no change alarm information is detected). In the event of a power transformer fault, the AC / DC converter is controlled to automatically shut down. The 380V AC dual power supply transfer switch can adopt an automatic transfer and automatic reset working mode. The transfer switch automatically switches after detecting an abnormal voltage, with a switching interval not exceeding a preset threshold (e.g., 1.5s (adjustable)) (i.e., when an abnormal voltage is detected in the AC dual power supply transfer switch, the transfer switch is controlled to switch). After the PCS of the AC energy storage system autonomously detects an abnormal voltage, it switches to off-grid mode (i.e., AC voltage source mode) (that is, when an abnormal voltage is detected in the converter energy storage device of the AC energy storage system, the system controls the AC voltage source mode to switch to off-grid mode). After the dual power supply transfer switch completes the backup circuit switching, the AC PCS detects voltage at the input of the controllable switch and can switch to grid-connected operation using self-synchronization (closing the controllable switch). The 380V AC bus is powered by a portable power adapter (that is, when voltage is detected at the input of the controllable switch of the converter energy storage device, the controllable switch is closed, and the power supply terminal of the AC bus is changed to an electronic transformer).

[0051] Optionally, after closing the controllable switch and changing the power supply end of the AC bus to an electronic transformer, the method further includes: determining whether the power transformer is supplying power normally; if the power transformer is supplying power normally, controlling the switching switch to switch to a preset circuit; and after the switching switch is switched to the preset circuit, controlling the converter energy storage device to switch to grid-connected operation.

[0052] In this embodiment of the invention, after the power supply of the II circuit is normal (i.e., under the condition that the power transformer is supplying power normally), the DC circuit breaker is closed and the dual power supply switching switch automatically switches to the preset circuit (i.e., the pre-set main circuit). During the switching process, the PCS (i.e., the converter energy storage device) of the AC energy storage system automatically switches to grid-connected operation after the switching is completed.

[0053] Optionally, after using a power transformer to supply power to the AC bus and using an electronic transformer as a backup power source for the AC bus, the method further includes: using a central controller to determine whether the electronic transformer has malfunctioned based on the signal information of the electronic transformer; and controlling the electronic transformer to shut down in the event of a malfunction.

[0054] In this embodiment of the invention, the central controller can make an I-channel fault judgment based on the WG fault total signal and DC fault total signal (i.e., the signal information of the electronic transformer) forwarded by the mobile power adapter (i.e., the central controller judges whether the electronic transformer has a fault based on the signal information of the electronic transformer). If the electronic transformer has a fault, the power adapter stops (i.e., the electronic transformer is controlled to stop).

[0055] Optionally, after controlling the electronic transformer to shut down, the method further includes: determining whether the electronic transformer is powered normally; if the electronic transformer is powered normally, issuing a one-button start command to control the electronic transformer to start and connect to the grid, wherein the one-button start command includes at least one of the following: one-button start command for electronic transformer, one-button start command for AC / DC converter, and one-button start command for DC energy storage device.

[0056] In this embodiment of the invention, the 380V AC bus power supply mode is the same as the normal operation mode. After the I-channel power supply is normal (i.e., when the electronic transformer power supply is normal), the power adapter can be controlled to start grid connection by issuing a one-click start command to the device through the background.

[0057] In this embodiment, the one-button start command includes: an electronic transformer one-button start command (i.e., a power adapter one-button start command), an AC / DC converter one-button start command (i.e., an ACDC one-button start command), and a DC energy storage device one-button start command (i.e., a DCDC one-button start command), wherein,

[0058] One-button start command for the power adapter: Start the high-voltage side of the power adapter; after determining that the WG signal of the power adapter is normal and the voltage is established, set the DC working mode of the power adapter; adjust the droop coefficient to the preset threshold (e.g., 0.15 (error less than 0.01)), adjust the voltage to the preset threshold (e.g., 750V (error less than 6V)); start the low-voltage side and establish a 380V voltage; close the adapter DC circuit breaker and reset the one-button start pressure plate of the power adapter.

[0059] ACDC one-button start command: Issues an ACDC power-on command; sets the ACDC operating status to constant voltage mode and enables droop; adjusts the droop coefficient to a preset threshold (e.g., 0.15 (error less than 0.01)) and adjusts the voltage to a preset threshold (e.g., 755V (error less than 6V)); establishes a DC 750V voltage, and the ACDC start-up is complete; closes the ACDC DC circuit breaker and resets the ACDC one-button start pressure plate.

[0060] One-button start command for DC-DC converter: Set the DC bus voltage to 750V; enable DC-DC droop and preset the droop coefficient to a preset threshold (e.g., 0.15 (error less than 0.01)); set the DC-DC operating mode to constant voltage mode and then execute the start command; complete the DC-DC bus voltage establishment; close the DC energy storage DC-DC bus circuit breaker and reset the one-button start pressure plate of DC-DC converter.

[0061] Alternatively, in the event of a dual-path fault (i.e., the power adapter and transformer substation are out of service), the central controller can determine the I-path and II-path faults based on the WG fault total signal and DC fault total signal forwarded by the portable power adapter and the three-phase voltage (whether there is a voltage loss) on the low-voltage side of the transformer substation. At the same time, it can detect whether there is a DC circuit breaker tripping alarm signal. If there is no such alarm signal, the DC circuit breaker will trip again. The portable power adapter and AC / DC converter will automatically shut down. The switching switch will be in the double-open position (double voltage loss double-open). After the PCS of the AC energy storage system detects the voltage abnormality, it will switch to off-grid mode (AC voltage source mode) and the 380V AC bus will be powered by the AC energy storage converter PCS. After the fault disappears, a one-button start command can be issued to the equipment through the background. After the PCS of the AC energy storage system detects the voltage at the input of the controllable switch, it will switch to grid-connected operation using self-synchronization. The 380V AC bus will be powered by the transformer substation.

[0062] Optionally, before balancing the power of the first and second power supplies of the DC bus, the following steps are also included: based on the voltage information of the power transformer, the central controller determines whether the second power supply has a fault and detects whether there is a change alarm information of the DC circuit breaker tripping input signal; if no change alarm information is detected, the DC circuit breaker is re-tripped; if the second power supply has a fault, the AC / DC converter is controlled to shut down.

[0063] In this embodiment of the invention, the central controller can make a fault judgment for the second power supply based on the low-voltage side data information of the transformer substation (i.e., based on the voltage information of the power transformer, the central controller judges whether the second power supply has failed). Simultaneously, it detects whether there is a change alarm information for the DC circuit breaker's open-circuit breaker signal. If no such alarm information is found, the DC circuit breaker is re-tripped (i.e., in the event of a fault in the second power supply, the AC / DC converter is shut down). In the event of a fault in the second power supply, the AC / DC converter is automatically shut down. In this embodiment, the DC bus load is shared by the DC energy storage converter and the portable power adapter. Both the DC energy storage converter and the portable power adapter operate in DC voltage source mode, jointly supporting the 750V DC bus voltage.

[0064] Optionally, before controlling the power balancing of the first and second power supplies of the DC bus, the method further includes: using a central controller to determine whether the first power supply has a fault based on the signal information of the electronic transformer; and controlling the electronic transformer to shut down in the event of a fault in the electronic transformer.

[0065] In this embodiment of the invention, the central controller can make a fault judgment on the first power supply based on the gateway fault total and DC / AC fault total signals forwarded by the portable power adapter (i.e., based on the signal information of the electronic transformer, the central controller judges whether the first power supply has failed). In the event of a fault in the electronic transformer, the power adapter is controlled to automatically shut down. In this embodiment, the DC bus load is jointly borne by the DC energy storage converter and the AC / DC converter. The DC energy storage converter and the AC / DC converter still operate in DC voltage source mode, jointly supporting the DC 750V bus voltage.

[0066] Step S102: In normal operation mode, control the power balance of the first and second power supplies of the DC bus.

[0067] In this embodiment of the invention, the DC bus can be connected to a DC energy storage converter, a portable power adapter, and an AC / DC converter. The portable power adapter, AC / DC converter, and DC energy storage converter all operate in voltage droop mode, jointly supporting the DC bus voltage. In normal operation mode, the power balance of the first and second power supplies of the DC bus can be controlled.

[0068] Optionally, the steps for controlling the power balancing of the first and second power supplies of the DC bus include: when both the electronic transformer and the preset converter are operating in voltage droop mode, controlling the microgrid system controller to coordinate the power between the voltage source of the electronic transformer and the voltage source of the preset converter; when the output power difference between the electronic transformer and the preset converter is greater than a preset threshold, performing power balancing control; representing the average output power of the electronic transformer and the preset converter as the current output target power; when the current power of the electronic transformer is not equal to the target power, changing the droop coefficient of the electronic transformer and changing the droop coefficient of the preset converter to complete the power balancing control of the first and second power supplies of the DC bus.

[0069] In this embodiment of the invention, the rated power of the power adapter can be set to 500kW, naturally distributed between the 750V DC port and the 380V AC port. Four AC charging piles, each with a rated power of 7kW, can be installed on the AC bus; six DC charging piles, each with a rated power of 180kW, can be installed on the DC bus. That is, the total load on the AC bus is 28kW, and the total load on the DC bus is 1080kW. Under normal operating conditions, the power adapter serves as a backup power source for the 380V AC bus, and there is no power output at the 380V AC port.

[0070] In this embodiment, both the power adapter and the AC / DC converter (i.e., the preset converter) operate in voltage droop mode to jointly support the stability of the bus voltage. The microgrid system controller coordinates the power of these two voltage sources to achieve power output balance (i.e., controls the microgrid system controller to coordinate the power between the voltage source of the electronic transformer and the voltage source of the preset converter). When the output power difference between the power adapter and the AC / DC converter exceeds a set limit, power balancing control is performed. The average output power of the power adapter and AC / DC converter is its current target output power. If the current power of the power adapter is greater than the target power, its output is reduced by changing its droop coefficient, while the droop coefficient of the DC / DC converter is increased by changing its droop coefficient. If the current power of the power adapter is less than the target power, its output is increased by changing its droop coefficient, while the droop coefficient of the DC / DC converter is reduced by changing its droop coefficient (that is, when the current power of the electronic transformer is not equal to the target power, the droop coefficient of the electronic transformer is changed, and the droop coefficient of the preset converter is changed to complete the power balance control of the first and second power supplies of the DC bus).

[0071] Step S103: When the active power on the low-voltage outgoing main switch of the power transformer flows to the high-voltage side, and / or when the active power is greater than the preset reverse power limit, control the reverse power operation.

[0072] In this embodiment of the invention, in order to prevent the power on the low-voltage outgoing main switch of the transformer substation from flowing back into the main grid, when the active power on the low-voltage outgoing main switch of the power transformer flows to the high-voltage side, and / or when the active power is greater than the preset reverse power limit, it is necessary to control the reverse power operation.

[0073] Optionally, when active power flows from the low-voltage outgoing main switch of the power transformer to the high-voltage side, and / or when the active power exceeds a preset reverse power limit, the steps for controlling reverse power operation include: when the DC energy storage device is discharging, reducing the discharge power of the DC energy storage device according to a first preset threshold; when the DC energy storage device is charging, increasing the charging power of the DC energy storage device according to a second preset threshold; when the power of the DC energy storage device cannot be controlled and / or the reverse power cannot be eliminated after control, controlling the power adjustment of the AC energy storage device; and when the reverse power cannot be eliminated after controlling the power of the DC energy storage device and controlling the AC energy storage device, controlling the power generation of the photovoltaic system.

[0074] In this embodiment of the invention, if the active power on the low-voltage outgoing main switch of the transformer substation flows to the high-voltage side and exceeds the reverse power limit, the reverse power control process needs to be initiated (i.e., when the active power on the low-voltage outgoing main switch of the power transformer flows to the high-voltage side, and / or the active power exceeds the preset reverse power limit, reverse power operation is controlled). In this embodiment, the power of the DC energy storage DC-DC converter can be controlled preferentially. If the DC energy storage DC-DC converter is discharging, the discharge power is reduced (i.e., when the DC energy storage device is discharging, the discharge power of the DC energy storage device is reduced according to a first preset threshold); if the DC energy storage DC-DC converter is charging, the charging power is increased (i.e., when the DC energy storage device is charging, the charging power of the DC energy storage device is increased according to a second preset threshold). If the power of the DC energy storage DC-DC converter cannot be controlled, or if reverse power cannot be eliminated after control, then the power of the AC energy storage PCS is controlled according to the same logic as controlling the power of the DC energy storage DC-DC converter (i.e., if the power of the DC energy storage cannot be controlled and / or reverse power cannot be eliminated after control, the power of the AC energy storage is adjusted). That is, if the AC energy storage PCS is discharging, then the discharging power is reduced; if the AC energy storage PCS is charging, then the charging power is increased. If reverse power still cannot be eliminated after controlling the DC energy storage DC-DC converter and the AC energy storage PCS, then the output of the photovoltaic system is adjusted, that is, the power generation of the photovoltaic system is reduced (i.e., if reverse power cannot be eliminated after controlling the power of the DC energy storage and the AC energy storage is controlled, the power generation of the photovoltaic system is controlled).

[0075] Optionally, it also includes: charging and discharging control of energy storage in normal operating mode.

[0076] In this embodiment of the invention, under normal operating mode (i.e., power supply I and II are operating normally), intelligent maintenance and peak shaving and valley filling control (i.e., charging and discharging control of energy storage) are performed on the energy storage.

[0077] Optionally, in normal operating mode, the steps for controlling the charging and discharging of energy storage include: when charging the AC energy storage device, determining that the maximum charging power of the AC energy storage device is less than or equal to the maximum allowable charging power given by the AC energy storage device; when discharging the AC energy storage device, selecting the minimum power between the maximum allowable discharge power given by the AC energy storage device and the AC load power as the maximum discharge power of the AC energy storage device; when charging the DC energy storage device, calculating the difference between the photovoltaic power generation power and the current DC charging load to obtain the initial power; adding a preset power value to the initial power to obtain the target power; selecting the minimum power between the target power and the maximum allowable charging power given by the DC energy storage device as the maximum charging power of the DC energy storage device; and when discharging the DC energy storage device, calculating the difference between the DC load power and the photovoltaic power generation power, and selecting the minimum power between the maximum allowable discharge power given by the DC energy storage device and the difference as the maximum discharge power of the DC energy storage device.

[0078] In this embodiment of the invention, for the AC energy storage PCS system: charging is performed if charging is required; discharging is performed if discharging is required; if it can be both charged and discharged, discharging occurs during peak hours and charging occurs during off-peak hours. When charging AC energy storage, the charging power is not greater than the maximum allowable charging power given by the AC energy storage PCS (i.e., when charging the AC energy storage device, the maximum charging power of the AC energy storage device is determined to be less than or equal to the maximum allowable charging power given by the AC energy storage device). When discharging AC energy storage, the maximum discharge power = min(the maximum allowable discharge power given by the AC energy storage PCS, AC load power) (i.e., when discharging the AC energy storage device, the minimum power between the maximum allowable discharge power given by the AC energy storage device and the AC load power is selected as the maximum discharge power of the AC energy storage device). For DC energy storage DC-DC: charging is performed if charging is required; discharging is performed if discharging is required; if it can be both charged and discharged, discharging occurs during peak hours and charging occurs during off-peak hours. When charging a DC energy storage DC-DC converter, the maximum charging power is calculated as follows: min(maximum allowable charging power given by the DC energy storage, 1000 + photovoltaic power generation - current DC charging load). This means that when charging the DC energy storage, the difference between the photovoltaic power generation and the current DC charging load is first calculated to obtain the initial power. The initial power is then increased by a preset power value (set to 1000 in this embodiment) to obtain the target power. The minimum power between the target power and the maximum allowable charging power given by the DC energy storage is selected as the maximum charging power of the DC energy storage. When discharging a DC energy storage DC-DC converter, the maximum discharge power is calculated as follows: min(maximum allowable discharge power given by the DC energy storage, DC charging load - photovoltaic power generation). This means that when discharging the DC energy storage, the difference between the DC load power and the photovoltaic power generation is calculated, and the minimum power between the maximum allowable discharge power given by the DC energy storage and the difference is selected as the maximum discharge power of the DC energy storage. In this embodiment, to ensure the power supply reliability of the AC / DC system, during the discharge process of the AC energy storage PCS system and the DC energy storage DC-DC converter, if the SOC is less than a preset threshold (e.g., 0.5), the discharge is stopped.

[0079] Another alternative is to calculate the discharge capacity of energy storage peak shaving and valley filling using the following three methods:

[0080] (1) Calculate using the readings of bidirectional meters installed on the energy storage connection bus line.

[0081] The meter readings of the energy storage discharge direction in the bidirectional meter are read in real time, and the discharge amount of a single peak shaving and valley filling is calculated based on the meter readings at the beginning and end of the peak shaving period of the peak shaving and valley filling function module.

[0082] (2) Calculate using the real-time active power values ​​transmitted by DC energy storage DC-DC and AC energy storage PCS.

[0083] The real-time power transmitted from DC energy storage DC-DC and AC energy storage PCS is integrated during the peak shaving and valley filling period to obtain the single peak shaving and valley filling discharge quantity.

[0084] (3) Calculate using the battery SOE (remaining charge) value sent by the battery BMS system.

[0085] Based on the actual situation, since there are no electricity meters installed on the bus line connecting the energy storage system, methods (2) and (3) are used to calculate the energy storage peak shaving and valley filling discharge.

[0086] The following describes in detail another optional implementation method.

[0087] Figure 2 This is a schematic diagram of an optional control system structure according to an embodiment of the present invention, such as... Figure 2 As shown, it includes: a local control layer, a coordination control layer, and an optimization scheduling layer. The local control layer is used for equipment power output control, AC / DC voltage control, and equipment operating mode control. The coordination control layer is used for operating mode switching, DC power sharing, and reverse power control. The optimization scheduling layer is used for microgrid operation monitoring, grid peak shaving and valley filling, and one-click system start-up, as detailed below:

[0088] In this embodiment, the microgrid control system adopts a three-tiered control structure: The first tier is the local control layer, which mainly controls the autonomous operation of micro-sources such as power adapters, distributed power sources, and energy storage in the microgrid. Its primary control objective is to maintain stable AC and DC bus voltages, achieve system power balance, and ensure stable operation of the hybrid microgrid. The main functions of this layer include equipment power output control, AC / DC voltage control, and equipment operating mode control. The second tier is the coordination control layer, which coordinates the entire microgrid system. It can control the microgrid's operating mode switching according to the actual operating conditions, ensuring safe load transfer in case of faults or abnormalities. During hybrid microgrid grid-connected operation, it allocates DC interconnection transmission power to prevent backfeeding of power from the microgrid to the distribution network. The main functions of this layer include operating mode switching, DC power sharing, and reverse power control. The third tier is the optimization scheduling layer, whose main objective is to achieve comprehensive system monitoring and energy-optimized operation. The main functions of this layer include microgrid operation monitoring, grid peak shaving and valley filling, and one-button system start-up.

[0089] In this embodiment, the control system can be divided into three layers according to the logic of operation control function: local control layer, fast coordination control layer and optimization scheduling layer. The three layers are connected by a hierarchical, distributed and open network.

[0090] The optimized scheduling layer includes equipment such as servers that also function as operator workstations, remote data communication gateways, and network printers. The optimized scheduling layer provides a human-machine interface for station operators, enabling functions such as managing and controlling the local control layer and quickly coordinating control layer equipment. It also communicates with the remote dispatch center to meet the requirements of unattended operation.

[0091] The devices in the rapid coordination control layer enable the central controller to access data and implement strategy control for mobile adapters, AC / DC converters, and energy storage converters.

[0092] The devices in the local control layer include portable power adapters, AC / DC converters, energy storage systems, and AC / DC charging piles, enabling stable local control.

[0093] Table 1 shows one of the optional coordination controller functions, as follows:

[0094] Table 1

[0095]

[0096] Figure 3 This is a schematic diagram of an optional coordination control device hardware architecture according to an embodiment of the present invention, such as... Figure 3 As shown, the internal bus includes: main CPU, DSP, and FPGA. The main CPU is connected to the serial port, indicator lights, monitoring network 1, and monitoring network 2 respectively. The FPGA is connected to control network 1, control network 2, and time synchronization respectively. The expansion bus is connected to the DI distributed installation functional modules (local acquisition units), DO distributed installation functional modules (local acquisition units), DC distributed installation functional modules (local acquisition units), AC distributed installation functional modules (local acquisition units), AI distributed installation functional modules (local acquisition units), and AO distributed installation functional modules (local acquisition units).

[0097] In this embodiment, the coordination control strategy is as follows:

[0098] 1) Communication area control strategy.

[0099] (1) Normal operating mode,

[0100] The 380V AC bus is powered by the transformer substation (II circuit), and the portable power adapter serves as a backup power source for the 380V AC bus. The PCS of the AC energy storage system operates in P / Q source mode and receives system commands for power distribution.

[0101] (2) Circuit II fault (substation out of service),

[0102] The central controller makes a fault judgment on the II circuit based on the three-phase voltage (whether there is a voltage loss) on the low-voltage side of the transformer. At the same time, it checks whether there is a change alarm information for the DC circuit breaker switch input signal. If there is no such change alarm information, the 750V side DC circuit breaker will trip again after a delay.

[0103] The AC / DC converter shuts down automatically.

[0104] The 380V AC dual power supply transfer switch adopts an automatic transfer and automatic reset working mode. The transfer switch automatically switches after detecting abnormal voltage, and the switching interval is no more than 1.5s (adjustable).

[0105] After the PCS of the AC energy storage system detects an abnormal voltage, it switches to off-grid mode (AC voltage source mode) for operation.

[0106] After the dual power supply transfer switch completes the backup circuit switching, the AC PCS detects that there is voltage at the input of the controllable switch and switches to grid-connected operation in a self-synchronizing manner (closing the controllable switch). The 380V AC bus is powered by the portable power adapter.

[0107] After the power supply to the second circuit is normal, the control DC circuit breaker and the dual power supply transfer switch will automatically switch to the main circuit. During the switching process, the PCS (converter energy storage device) of the AC energy storage system will automatically switch to grid-connected operation after the switching is completed.

[0108] (3) I-channel fault (power adapter upstream stage out of operation),

[0109] The central controller makes a fault judgment on the I-channel based on the WG fault total signal and DC fault total signal forwarded by the portable power adapter, and the power adapter shuts down.

[0110] The 380V AC bus power supply mode is the same as the normal operation mode. After the I-channel power supply is normal, the operator controls the power adapter to start grid connection by issuing a one-button start command to the equipment through the background.

[0111] (4) Dual-circuit fault (power adapter and transformer substation out of service),

[0112] The central controller makes fault judgments on the I-channel and II-channel based on the WG fault total signal and DC fault total signal forwarded by the portable power adapter and the three-phase voltage (whether there is a voltage loss) on the low-voltage side of the transformer. At the same time, it checks whether there is a change alarm information for the DC circuit breaker tripping input signal. If there is no such change alarm information, the DC circuit breaker will be re-tripped.

[0113] The portable power adapter and AC / DC converter automatically shut down. The changeover switch is in the dual-off position (dual undervoltage dual-off).

[0114] After the PCS of the AC energy storage system detects an abnormal voltage, it switches to off-grid mode (AC voltage source mode) and the 380V AC bus is powered by the AC energy storage converter PCS.

[0115] After the fault disappeared, the operator issued a one-click start command for the equipment through the background. After the PCS of the AC energy storage system detected that the input of the controllable switch was energized, it switched to grid-connected operation in a self-synchronizing mode, and the 380V AC bus was powered by the box-type substation.

[0116] 2) DC area control strategy.

[0117] The DC bus connects to the DC energy storage converter, the portable power adapter, and the AC / DC converter.

[0118] The portable power adapter, AC / DC converter, and DC energy storage converter all operate in voltage droop mode, jointly supporting the DC bus voltage.

[0119] (1) Normal operating mode,

[0120] A, Control Target

[0121] DC bus I and II power supply power balance control.

[0122] B, Control equipment

[0123] Power adapters, AC / DC converters.

[0124] C, Constraints

[0125] Both the power adapter and the AC / DC converter operate in voltage droop mode and function normally. The reference voltage for both the power adapter and the AC / DC converter is set to 750V, within the acceptable DC bus voltage range [700V, 770V]: the power adapter's droop coefficient has a maximum value of 0.07, a minimum value of 0.01, and an adjustment step of 0.01; the AC / DC converter's droop coefficient also has a maximum value of 0.07, a minimum value of 0.01, and an adjustment step of 0.01. Communication between the central controller and the power adapter follows the IEC104 protocol, while communication with the AC / DC converter follows the MODBUS TCP protocol. Due to communication rate limitations, the central controller's power balancing coordination control effect is on the order of seconds; transient voltage stabilization control after load surges is the responsibility of the power adapter and the AC / DC converter.

[0126] D, Control Flow

[0127] The power adapter has a rated power of 500kW, naturally distributed across the 750V DC port and the 380V AC port. There are 4 AC charging stations on the AC bus, each with a rated power of 7kW; and 6 DC charging stations on the DC bus, each with a rated power of 180kW. This means the total load on the AC bus is 28kW, and the total load on the DC bus is 1080kW. Under normal operating conditions, the power adapter serves as a backup power source for the 380V AC bus, and there is no power output at the 380V AC port.

[0128] Both the power adapter and the AC / DC converter operate in voltage droop mode, working together to stabilize the bus voltage. The microgrid system controller coordinates the power of these two voltage sources to achieve power output balance.

[0129] Power balancing control is implemented when the output power difference between the power adapter and the AC / DC converter exceeds a set limit. The average output power of the power adapter and the AC / DC converter is its current target output power. If the current power of the power adapter is greater than the target power, its output is reduced by changing its droop coefficient, while the droop coefficient of the DC / DC converter is increased by changing its droop coefficient. Conversely, if the current power of the power adapter is less than the target power, its output is increased by changing its droop coefficient, while the droop coefficient of the DC / DC converter is reduced by changing its droop coefficient.

[0130] (2) Channel II fault,

[0131] The central controller makes a fault judgment on the II circuit based on the low-voltage side data information of the transformer substation, and at the same time checks whether there is a change alarm information of the DC circuit breaker switch input signal. If there is no such change alarm information, the DC circuit breaker will be re-tripped.

[0132] The AC / DC converter shuts down automatically. The DC bus load is shared by the DC energy storage converter and the portable power adapter. The DC energy storage converter and the portable power adapter still operate in DC voltage source mode, jointly supporting the DC 750V bus voltage.

[0133] To ensure seamless switching and stable operation of the DC system in the event of a dual-path failure after a II power supply failure, the maximum charging load of the DC bus is limited to the maximum power output of the DC-DC converter after a II power supply failure.

[0134] To ensure the reliability of energy storage when powered independently during N-2, the energy storage DC-DC converter is float-charged. At this time, the power adapter is powered independently. Considering the power of the low-voltage AC port of the power adapter (AC charging device power + station service transformer), the maximum charging load of the DC bus is limited to no more than 400kW.

[0135] After the power supply to the second circuit is normal, the AC / DC converter is started and connected to the grid by controlling the one-button start command, restoring the normal operation mode and removing the limit on the maximum charging load of the DC bus.

[0136] (3) Circuit I fault (power adapter exits DC 750V bus voltage support mode),

[0137] The central controller makes a fault judgment on the I-channel based on the gateway fault signal and the DC / AC fault signal forwarded by the portable power adapter, and the power adapter shuts down automatically.

[0138] The DC bus load is shared by the DC energy storage converter and the AC-DC converter. The DC energy storage converter and the AC-DC converter still operate in DC voltage source mode, jointly supporting the DC 750V bus voltage.

[0139] To ensure seamless switching and stable operation of the DC system in the event of a dual-path failure after a failure of the I-path power supply, the maximum charging load of the DC bus is limited to the maximum power output of the DC-DC converter after a failure of the I-path power supply.

[0140] To ensure the reliability of energy storage when powered independently during N-2, the energy storage DC-DC converter is float-charged. At this time, the ACDC converter is powered independently, limiting the maximum charging load of the DC bus to no more than 450kW (maximum discharge output power of DC-DC converter * 0.9).

[0141] After the I-channel power supply is normal, the central controller controls the movable power adapter to start grid connection via a one-button start command, restoring normal operation mode and removing the limit on the maximum charging load of the DC bus.

[0142] (4) Dual-path fault (power adapter and AC / DC converter out of service),

[0143] The central controller determines faults on paths I and II based on the gateway fault signal, the DC / AC fault signal forwarded by the portable power adapter, and the three-phase voltage (whether there is a voltage loss) on the low-voltage side of the transformer substation. Simultaneously, it checks for any DC circuit breaker tripping alarm signals. If no such alarm is detected, the DC circuit breaker is re-tripped. The portable power adapter and AC / DC converter automatically shut down.

[0144] The DC energy storage converter still operates in DC voltage source mode, supporting a DC 750V bus voltage and limiting the maximum charging load of the DC bus to no more than 450kW (maximum DC DCDC discharge output power * 0.9).

[0145] After the fault disappeared, the operator issued a one-click start command for the equipment through the background, and the DC bus returned to normal operation mode. The power adapter, AC / DC converter and DC energy storage converter jointly supported the 750V DC bus.

[0146] 3) Reverse power control.

[0147] (1) Control objectives,

[0148] To prevent power from flowing back into the main grid from the low-voltage outgoing main switch of the transformer substation.

[0149] (2) Control equipment,

[0150] AC energy storage PCS, DC energy storage DC-DC, photovoltaic DC-DC.

[0151] (3) Constraints

[0152] The AC energy storage PCS operates in PQ mode, the DC energy storage DC-DC operates in voltage droop mode, and the photovoltaic DC-DC operates in maximum power point tracking mode.

[0153] (4) Control process,

[0154] If the active power on the low-voltage outgoing main switch of the transformer substation flows to the high-voltage side and exceeds the reverse power limit, the reverse power control process needs to be initiated. Priority is given to controlling the power of the DC energy storage DC-DC converter. If the DC energy storage DC-DC converter is discharging, the discharging power is reduced; if the DC energy storage DC-DC converter is charging, the charging power is increased. If the power of the DC energy storage DC-DC converter cannot be controlled, or if controlling it fails to eliminate the reverse power, the power of the AC energy storage PCS is controlled according to the same logic as controlling the DC energy storage DC-DC converter. That is, if the AC energy storage PCS is discharging, the discharging power is reduced; if the AC energy storage PCS is charging, the charging power is increased. If controlling the DC energy storage DC-DC converter and the AC energy storage PCS still fails to eliminate the reverse power, the output of the photovoltaic system is adjusted, i.e., the photovoltaic system's power generation is reduced.

[0155] 4) Intelligent maintenance and peak shaving / valley filling of energy storage SOC.

[0156] (1) Control objectives,

[0157] Maintain the energy storage SOC within a reasonable range, discharging the energy storage during peak electricity consumption periods and charging the energy storage during off-peak electricity consumption periods.

[0158] (2) Control equipment,

[0159] AC energy storage PCS, DC energy storage DCDC.

[0160] (3) Constraints

[0161] AC energy storage operates in PQ mode, and DC energy storage operates in voltage droop mode. The default value of the droop coefficient is 0.03. The discharge power of the energy storage system cannot exceed the maximum discharge power given by the battery management system, and the discharge cannot cause power to flow back into the distribution network. The charging power of the energy storage system cannot exceed the maximum charging power given by the battery management system, and the charging cannot cause the power adapter and AC / DC converter to overload.

[0162] (4) Control process,

[0163] Under normal operating conditions (both I and II power supplies are operating normally), intelligent maintenance and peak shaving / valley filling control are implemented for energy storage.

[0164] For AC energy storage PCS systems:

[0165] A. If charging is needed, then charge; if discharging is needed, then discharge; if it can be both charged and discharged, then discharge during peak hours and charge during off-peak hours.

[0166] B. When charging AC energy storage, the charging power shall not exceed the maximum allowable charging power given by the AC energy storage PCS.

[0167] C. During AC energy storage discharge, the maximum discharge power = min (the maximum allowable discharge power given by the AC energy storage PCS, and the AC load power).

[0168] For DC energy storage DC-DC converters:

[0169] A. If charging is needed, then charge; if discharging is needed, then discharge; if it can be both charged and discharged, then discharge during peak hours and charge during off-peak hours.

[0170] B. When DC energy storage is charging via DC-DC converter, the maximum charging power = min(maximum allowable charging power given by DC energy storage, 1000 + photovoltaic power generation - current DC charging load).

[0171] C. When DC energy storage DC-DC discharges, the maximum discharge power = min(maximum allowable discharge power given by DC energy storage, DC charging load - photovoltaic power generation).

[0172] D. To ensure the reliability of power supply in AC / DC systems, if the SOC is less than 0.5 during the discharge process of AC energy storage PCS system and DC energy storage DCDC, the discharge will be stopped.

[0173] (5) There are three methods for calculating the discharge capacity of energy storage peak shaving and valley filling:

[0174] Method 1: Calculate using the readings of bidirectional meters installed on the energy storage connection bus line.

[0175] The meter readings of the energy storage discharge direction in the bidirectional meter are read in real time, and the discharge amount of a single peak shaving and valley filling is calculated based on the meter readings at the beginning and end of the peak shaving period of the peak shaving and valley filling function module.

[0176] Method 2: Calculate using the real-time active power values ​​transmitted from DC energy storage DC-DC converters and AC energy storage PCS.

[0177] The real-time power transmitted from DC energy storage DC-DC and AC energy storage PCS is integrated during the peak shaving and valley filling period to obtain the single peak shaving and valley filling discharge quantity.

[0178] Method 3: Calculate using the battery SOE (remaining charge) value sent by the battery BMS system.

[0179] Based on the actual situation, since there are no electricity meters installed on the bus line connecting the energy storage system, methods 2 and 3 are used to calculate the peak shaving and valley filling discharge of the energy storage system.

[0180] 5) One-click start.

[0181] (1) One-button start for the power adapter

[0182] Power adapter high-voltage side start-up;

[0183] After confirming that the WG signal of the power adapter is normal and that voltage has been established, set the power adapter to DC operating mode;

[0184] Adjust the droop factor to 0.15 (error less than 0.01), and adjust the voltage to 750V (error less than 6V);

[0185] Start-up on the low-voltage side establishes 380V voltage;

[0186] Close the adapter DC circuit breaker and reset the power adapter one-button start pressure plate.

[0187] (2) ACDC One-Click Start

[0188] Issue the AC / CDC power-on command;

[0189] Set the AC / DC converter to constant voltage mode and enable droop.

[0190] Adjust the droop factor to 0.15 (error less than 0.01) and adjust the voltage to 755V (error less than 6V);

[0191] Establish 750V DC voltage; AC / DC startup complete.

[0192] Close the AC / DC circuit breaker and reset the AC / DC one-button start pressure plate.

[0193] (3) One-click start of DC-DC

[0194] Set the DC bus voltage to 750V;

[0195] Set DC-DC droop enable and preset the droop coefficient to 0.15 (error less than 0.01);

[0196] After setting the DC-DC working mode to constant voltage mode, execute the power-on command;

[0197] The DC-DC bus voltage setup is complete;

[0198] Combine DC energy storage DC-DC bus circuit breaker and reset DC-DC one-button start pressure plate.

[0199] 6) Performance indicators.

[0200] Table 2 provides an example of an optional performance metric, as shown in Table 2:

[0201] Table 2

[0202]

[0203] In this embodiment of the invention, by combining the advantages of electric vehicle charging stations and energy storage power stations, bidirectional scheduling of battery energy can be achieved, making the control strategy of the integrated charging, discharging, and energy storage power station feature diversified functions and reduced operating costs. A power regulation system (PCS) can be installed within the integrated charging, discharging, and energy storage power station. This system consists of multiple PCS sub-modules connected in parallel, adopting a hierarchical control structure, and can operate in multiple operating modes according to the management and scheduling of the host computer.

[0204] Example 2

[0205] The power plant-based control device provided in this embodiment includes multiple implementation units, each of which corresponds to a specific implementation step in Embodiment 1 above.

[0206] Figure 4 This is a schematic diagram of an optional power station-based control device according to an embodiment of the present invention, such as... Figure 4 As shown, the control device may include: a power supply unit 40, a first control unit 41, and a second control unit 42, wherein...

[0207] The power supply unit 40 is used to supply power to the AC bus using a power transformer in normal operating mode, and to use an electronic transformer as a backup power source for the AC bus. The normal operating mode refers to the mode in which both the power transformer and the electronic transformer are operating normally.

[0208] The first control unit 41 is used to control the power balance of the first power supply and the second power supply of the DC bus in normal operation mode.

[0209] The second control unit 42 is used to control reverse power operation when active power flows from the low-voltage outgoing main switch of the power transformer to the high-voltage side, and / or when the active power is greater than the preset reverse power limit.

[0210] The aforementioned control device, in normal operating mode, uses a power transformer to supply power to the AC bus via the power supply unit 40, and an electronic transformer as a backup power source for the AC bus. In normal operating mode, the first control unit 41 controls the power balance of the first and second power sources on the DC bus. The second control unit 42 controls the flow of active power from the low-voltage outgoing main switch of the power transformer to the high-voltage side, and / or, if the active power exceeds a preset reverse power limit, controls reverse power operation. In this embodiment of the invention, when both the power transformer and the electronic transformer are operating normally, the power transformer can supply power to the AC bus, and the electronic transformer can serve as a backup power source for the AC bus. Controlling the power balance of the two power sources on the DC bus and controlling reverse power operation ensures the stability and safety of continuous power supply operation of the power station during the control process. It also increases functional versatility, reduces operating costs, and thus solves the technical problem in related technologies that cannot guarantee the stability and safety of continuous power supply operation of the power station.

[0211] Optionally, the control device further includes: a first judgment module, used to determine whether the power transformer has failed based on the voltage information of the power transformer after the power transformer is used to supply power to the AC bus and the electronic transformer is used as the backup power source for the AC bus, and to detect whether there is a change alarm information of the DC circuit breaker tripping input signal; a first re-tripping module, used to re-trip the DC circuit breaker if no change alarm information is detected; a first control module, used to control the AC-DC converter to shut down in the event of a power transformer failure; a second control module, used to control the switching switch to switch when an abnormal voltage is detected in the AC dual power supply switching switch; a third control module, used to control the AC voltage source mode to switch to off-grid mode operation when an abnormal voltage is detected in the converter energy storage device of the AC energy storage system; and a fourth control module, used to control the controllable switch to close and change the power supply terminal of the AC bus to the electronic transformer when a voltage is detected at the input terminal of the controllable switch of the converter energy storage device.

[0212] Optionally, the control device further includes: a second judgment module, used to determine whether the power transformer is supplying power normally after the controllable switch is closed and the power supply end of the AC bus is changed to the electronic transformer; a fifth control module, used to control the switching switch to switch to the preset circuit when the power transformer is supplying power normally; and a sixth control module, used to control the converter energy storage device to switch to grid-connected operation after the switching switch is switched to the preset circuit.

[0213] Optionally, the control device also includes: a third judgment module, used to determine whether the electronic transformer has malfunctioned based on the signal information of the electronic transformer after the power transformer is used to supply power to the AC bus and the electronic transformer is used as a backup power source for the AC bus; and a seventh control module, used to control the electronic transformer to shut down in the event of a malfunction.

[0214] Optionally, the control device further includes: a fourth judgment module, used to determine whether the electronic transformer is powered normally after the electronic transformer is shut down; and an eighth control module, used to issue a one-key start command to control the electronic transformer to start grid connection when the electronic transformer is powered normally, wherein the one-key start command includes at least one of the following: one-key start command for electronic transformer, one-key start command for AC DC generator, and one-key start command for DC energy storage device.

[0215] Optionally, the first control unit includes: a ninth control module, used to control the microgrid system controller to coordinate the power between the voltage source of the electronic transformer and the voltage source of the preset converter when both the electronic transformer and the preset converter are operating in voltage droop mode; a tenth control module, used to perform power balancing control when the output power difference between the electronic transformer and the preset converter is greater than a preset threshold; a first characterization module, used to characterize the average output power of the electronic transformer and the preset converter as the current output target power; and a first modification module, used to modify the droop coefficient of the electronic transformer and the droop coefficient of the preset converter when the current power of the electronic transformer is not equal to the target power, so as to complete the power balancing control of the first power supply and the second power supply of the DC bus.

[0216] Optionally, the control device further includes: a fifth judgment module, used to determine, based on the voltage information of the power transformer, whether the second power supply has a fault, and to detect whether there is a change alarm information of the DC circuit breaker tripping input signal before the power of the first and second power supplies of the DC bus is balanced; a second re-tripping module, used to re-trip the DC circuit breaker if no change alarm information is detected; and an eleventh control module, used to control the AC / DC converter to shut down in the event of a fault in the second power supply.

[0217] Optionally, the control device also includes: a sixth judgment module, used to determine whether the first power supply has a fault based on the signal information of the electronic transformer before the power balancing of the first and second power supplies of the DC bus is achieved; and a twelfth control module, used to control the electronic transformer to shut down in the event of a fault.

[0218] Optionally, the second control unit includes: a first reduction module, used to reduce the discharge power of the DC energy storage device according to a first preset threshold when the DC energy storage device is discharging; a first increase module, used to increase the charging power of the DC energy storage device according to a second preset threshold when the DC energy storage device is charging; a thirteenth control module, used to control the AC energy storage device to adjust its power when the power of the DC energy storage device cannot be controlled and / or the reverse power cannot be eliminated after control; and a fourteenth control module, used to control the power generation of the photovoltaic system when the power of the DC energy storage device is controlled and the reverse power cannot be eliminated after the AC energy storage device is controlled.

[0219] Optionally, the control device may also include a fifteenth control module for controlling the charging and discharging of the energy storage in normal operating mode.

[0220] Optionally, the fifteenth control module includes: a first determining submodule, used to determine that, when charging the AC energy storage device, the maximum charging power of the AC energy storage device is less than or equal to the maximum allowable charging power given by the AC energy storage device; a first selecting submodule, used to select the minimum power between the maximum allowable discharge power given by the AC energy storage device and the AC load power as the maximum discharge power of the AC energy storage device when discharging the AC energy storage device; a first calculating submodule, used to calculate the difference between the photovoltaic power generation power and the current DC charging load to obtain the initial power when charging the DC energy storage device; a first increasing submodule, used to increase the initial power by a preset power value to obtain the target power; a second selecting submodule, used to select the minimum power between the target power and the maximum allowable charging power given by the DC energy storage device as the maximum charging power of the DC energy storage device; and a second calculating submodule, used to calculate the difference between the DC load power and the photovoltaic power generation power when discharging the DC energy storage device, and select the minimum power between the maximum allowable discharge power given by the DC energy storage device and the difference as the maximum discharge power of the DC energy storage device.

[0221] The aforementioned control device may also include a processor and a memory. The power supply unit 40, the first control unit 41, the second control unit 42, etc., are all stored in the memory as program units, and the processor executes the aforementioned program units stored in the memory to realize the corresponding functions.

[0222] The aforementioned processor contains a kernel, which retrieves the corresponding program units from memory. One or more kernels can be configured to control reverse power operation when active power flows from the low-voltage main switch of the power transformer to the high-voltage side, and / or when the active power exceeds a preset reverse power limit, by adjusting kernel parameters.

[0223] The aforementioned memory may include non-permanent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM, and the memory includes at least one memory chip.

[0224] This application also provides a computer program product, which, when executed on a data processing device, is suitable for executing an initialization program with the following method steps: in normal operating mode, a power transformer is used to supply power to the AC bus, and an electronic transformer is used as a backup power source for the AC bus; in normal operating mode, the power balance of the first and second power sources of the DC bus is controlled; active power flows to the high-voltage side at the low-voltage outgoing main switch of the power transformer; and / or, if the active power is greater than a preset reverse power limit, reverse power operation is controlled.

[0225] According to another aspect of the present invention, an electronic device is also provided, including: a processor; and a memory for storing executable instructions of the processor; wherein the processor is configured to execute the above-described power plant-based control method by executing the executable instructions.

[0226] According to another aspect of the present invention, a computer-readable storage medium is also provided, the computer-readable storage medium including a stored computer program, wherein, when the computer program is executed, it controls the device where the computer-readable storage medium is located to perform the above-described power station-based control method.

[0227] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0228] In the above embodiments of the present invention, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0229] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection between units or modules may be electrical or other forms.

[0230] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0231] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0232] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0233] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A control method based on a power station, characterized in that, include: In normal operation mode, a power transformer is used to supply power to the AC bus, and an electronic transformer is used as a backup power source for the AC bus. The normal operation mode refers to a mode in which both the power transformer and the electronic transformer are operating normally. In the normal operating mode, the power of the first and second power supplies of the DC bus is balanced. The steps for controlling the power balancing of the first and second power supplies of the DC bus include: when both the electronic transformer and the preset converter are operating in voltage droop mode, controlling the microgrid system controller to coordinate the power between the voltage sources of the electronic transformer and the preset converter; when the output power difference between the electronic transformer and the preset converter is greater than a preset threshold, performing power balancing control; representing the average output power of the electronic transformer and the preset converter as the current output target power; when the current power of the electronic transformer is not equal to the target power, changing the droop coefficient of the electronic transformer and changing the droop coefficient of the preset converter to complete the power balancing control of the first and second power supplies of the DC bus. When the active power at the low-voltage outgoing main switch of the power transformer flows to the high-voltage side, and / or when the active power is greater than the preset reverse power limit, reverse power operation is controlled. The method further includes: after using a power transformer to supply power to the AC bus and an electronic transformer as a backup power source for the AC bus, the method also includes: based on the voltage information of the power transformer, using a central controller to determine whether the power transformer has malfunctioned and to detect whether there is a change alarm information for the DC circuit breaker tripping signal; if no change alarm information is detected, re-tripping the DC circuit breaker; if the power transformer malfunctions, controlling the AC-DC converter to shut down; if an abnormal voltage is detected at the switching switch of the AC dual power supply, controlling the switching switch to switch; if an abnormal voltage is detected at the converter energy storage device of the AC energy storage system, controlling the AC voltage source mode to switch to off-grid mode operation; and if a voltage is detected at the input of the controllable switch of the converter energy storage device, controlling the controllable switch to close and changing the power supply terminal of the AC bus to the electronic transformer. After controlling the controllable switch to close and changing the power supply terminal of the AC bus to the electronic transformer, the method further includes: determining whether the power transformer is supplying power normally; if the power transformer is supplying power normally, controlling the switching switch to switch to a preset circuit; and after the switching switch is switched to the preset circuit, controlling the converter energy storage device to switch to grid-connected operation. In the normal operating mode, the energy storage is charged and discharged, including: when charging the AC energy storage device, determining that the maximum charging power of the AC energy storage device is less than or equal to the maximum allowable charging power given by the AC energy storage device; when discharging the AC energy storage device, selecting the minimum power between the maximum allowable discharge power given by the AC energy storage device and the AC load power as the maximum discharge power of the AC energy storage device; when charging the DC energy storage device, calculating the difference between the photovoltaic power generation power and the current DC charging load to obtain the initial power; adding a preset power value to the initial power to obtain the target power; selecting the minimum power between the target power and the maximum allowable charging power given by the DC energy storage device as the maximum charging power of the DC energy storage device; when discharging the DC energy storage device, calculating the difference between the DC load power and the photovoltaic power generation power, and selecting the minimum power between the maximum allowable discharge power given by the DC energy storage device and the difference as the maximum discharge power of the DC energy storage device.

2. The control method according to claim 1, characterized in that, After employing a power transformer to supply power to the AC bus and using an electronic transformer as a backup power source for the AC bus, the method further includes: Based on the signal information of the electronic transformer, a central controller is used to determine whether the electronic transformer has malfunctioned. In the event of a malfunction in the electronic transformer, the electronic transformer shall be shut down.

3. The control method according to claim 2, characterized in that, After controlling the electronic transformer to shut down, the following steps are also included: Determine whether the electronic transformer is supplying power normally; When the electronic transformer is powered normally, a one-button start command is issued to control the electronic transformer to start and connect to the grid. The one-button start command includes at least one of the following: one-button start command for electronic transformer, one-button start command for AC / DC converter, and one-button start command for DC energy storage device.

4. The control method according to claim 1, characterized in that, Before controlling the power balancing of the first and second power supplies to the DC bus, the following is also included: Based on the voltage information of the power transformer, the central controller determines whether the second power supply has a fault and detects whether there is a change alarm information of the DC circuit breaker trip input signal. If no displacement alarm information is detected, the DC circuit breaker will be re-tripped; In the event of a failure in the second power supply, the AC / DC converter will be shut down.

5. The control method according to claim 1, characterized in that, Before controlling the power balancing of the first and second power supplies to the DC bus, the following is also included: Based on the signal information of the electronic transformer, the central controller is used to determine whether the first power supply has a fault. In the event of a malfunction in the electronic transformer, the electronic transformer shall be shut down.

6. The control method according to claim 1, characterized in that, When active power flows from the low-voltage outgoing main switch of the power transformer to the high-voltage side, and / or when the active power exceeds a preset reverse power limit, the steps for controlling reverse power operation include: When the DC energy storage device is discharging, the discharge power of the DC energy storage device is reduced according to a first preset threshold. While the DC energy storage device is being charged, the charging power of the DC energy storage device is increased according to a second preset threshold. In the event that the power of the DC energy storage device cannot be controlled and / or the reverse power cannot be eliminated after control, the power of the AC energy storage device is adjusted. When the reverse power cannot be eliminated after controlling the power of the DC energy storage device and the AC energy storage device, the power generation of the photovoltaic system is controlled.

7. A control device based on a power station, characterized in that, include: The power supply unit is used to supply power to the AC bus using a power transformer in normal operating mode, and to use an electronic transformer as a backup power source for the AC bus. The normal operating mode refers to a mode in which both the power transformer and the electronic transformer are operating normally. The first control unit is used to control the power balancing of the first and second power supplies of the DC bus in the normal operating mode. The first control unit includes: a ninth control module, used to control the microgrid system controller to coordinate the power between the voltage source of the electronic transformer and the voltage source of the preset converter when both the electronic transformer and the preset converter are operating in voltage droop mode; a tenth control module, used to perform power balancing control when the output power difference between the electronic transformer and the preset converter is greater than a preset threshold; a first characterization module, used to characterize the average output power of the electronic transformer and the preset converter as the current output target power; and a first modification module, used to modify the droop coefficient of the electronic transformer and the droop coefficient of the preset converter when the current power of the electronic transformer is not equal to the target power, so as to complete the power balancing control of the first power supply and the second power supply of the DC bus. The second control unit is used to control the reverse power operation when the active power at the low-voltage outgoing main switch of the power transformer flows to the high-voltage side, and / or when the active power is greater than the preset reverse power limit. The first judgment module is used to determine whether the power transformer has malfunctioned after the power transformer is used to supply power to the AC bus and the electronic transformer is used as the backup power source for the AC bus, based on the voltage information of the power transformer, and to detect whether there is a change-position alarm information of the DC circuit breaker input signal. The first re-trip module is used to re-trip the DC circuit breaker if no change-position alarm information is detected. The first control module is used to control the AC-DC converter to shut down when the power transformer malfunctions. The second control module is used to control the switching switch to switch when the voltage of the AC dual power supply switching switch is abnormal. The third control module is used to control the AC voltage source mode to switch to off-grid mode when the voltage of the AC energy storage system converter energy storage device is abnormal. The fourth control module is used to control the controllable switch of the converter energy storage device to close and change the power supply terminal of the AC bus to the electronic transformer when the input terminal of the controllable switch of the converter energy storage device is energized. The second judgment module is used to determine whether the power transformer is supplying power normally after controlling the controllable switch to close and changing the power supply terminal of the AC bus to the electronic transformer; the fifth control module is used to control the switching switch to switch to the preset circuit when the power transformer is supplying power normally; the sixth control module is used to control the converter energy storage device to switch to grid-connected operation after the switching switch is switched to the preset circuit. The fifteenth control module is used to control the charging and discharging of the energy storage under the normal operating mode. The fifteenth control module includes: a first determining submodule, used to determine that the maximum charging power of the AC energy storage device is less than or equal to the maximum allowable charging power given by the AC energy storage device when charging the AC energy storage device; a first selecting submodule, used to select the minimum power between the maximum allowable discharge power given by the AC energy storage device and the AC load power as the maximum discharge power of the AC energy storage device when discharging the AC energy storage device; a first calculating submodule, used to calculate the difference between the photovoltaic power generation power and the current DC charging load to obtain an initial power when charging the DC energy storage device; a first increasing submodule, used to increase the initial power by a preset power value to obtain a target power; a second selecting submodule, used to select the minimum power between the target power and the maximum allowable charging power given by the DC energy storage device as the maximum charging power of the DC energy storage device; and a second calculating submodule, used to calculate the difference between the DC load power and the photovoltaic power generation power when discharging the DC energy storage device, and select the minimum power between the maximum allowable discharge power given by the DC energy storage device and the difference as the maximum discharge power of the DC energy storage device.

8. An electronic device, characterized in that, include: processor; as well as Memory for storing the executable instructions of the processor; The processor is configured to execute the power plant-based control method according to any one of claims 1 to 6 by executing the executable instructions.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes a stored computer program, wherein, when the computer program is executed, it controls the device on which the computer-readable storage medium is located to perform the power plant-based control method according to any one of claims 1 to 6.

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