Alternating current coupling light storage and charging integrated system and control method thereof

Abstract

The invention discloses an alternating current coupling light storage and charging integrated system which comprises an energy storage assembly, a photovoltaic assembly, a charging pile assembly, a confluence power distribution assembly and a control assembly. The energy storage assembly comprises an energy storage battery pack, an energy storage converter and an energy storage controller. The energy storage battery pack is connected with the direct current end of the energy storage converter. The photovoltaic module comprises a photovoltaic array and a photovoltaic inverter, and the photovoltaic array is connected with the direct current input end of the photovoltaic inverter; the confluence power distribution assembly comprises a plurality of alternating-current circuit breakers and an alternating-current coupling bus, the alternating-current end of the energy storage converter, the alternating-current output end of the photovoltaic inverter and the charging pile assembly are connected with the alternating-current coupling bus through the alternating-current circuit breakers, and the alternating-current coupling bus is connected with a power grid; the control assembly comprises an industrial personal computer, a switch and a serial port server, and the industrial personal computer dispatches the flow direction and size of photovoltaic array power, energy storage battery pack power and power grid power in real time according to the load condition of the charging pile assembly, the power generation condition of the photovoltaic array, the state of the energy storage battery pack and the state of the power grid.

Description

Technical Field

[0001] This invention relates to the field of new energy technology, and in particular to an AC-coupled photovoltaic-storage-charging integrated system and its control method. Background Technology

[0002] The integration of photovoltaic power generation and electric vehicle charging facilities has become an important development direction in the energy sector. Photovoltaic-storage-charging systems integrate photovoltaic power generation, energy storage for peak shaving, and charging services, achieving clean energy production and efficient energy consumption. Among these, the AC-coupled architecture is widely used in distributed photovoltaic-storage-charging scenarios due to its advantages such as strong compatibility, modular expansion, and low difficulty in modifying existing power grids.

[0003] While existing AC-coupled photovoltaic-storage-charging systems have achieved basic functions, several technical bottlenecks remain in actual operation: First, poor grid adaptability. When grid voltage fluctuates or momentary power outages occur, the system is prone to grid disconnection and shutdown, unable to provide uninterrupted power to critical charging loads. Furthermore, manual restart is required after grid restoration, impacting user experience. Second, low energy dispatch efficiency. Existing systems mostly adopt a fixed logic of "direct photovoltaic supply + surplus energy storage + insufficient power supplementation," without combining photovoltaic irradiance prediction, charging load demand prediction, and energy storage SOC change trends for dynamic dispatch. This leads to high photovoltaic curtailment rates or frequent deep charging and discharging of energy storage, shortening energy storage lifespan. Third, inadequate fault diagnosis and protection. The system lacks comprehensive monitoring of the operating status of each unit, making it difficult to accurately locate inverter faults, individual battery cell failures, and other problems. Moreover, protection mechanisms are mostly simple overcurrent and overvoltage protections, resulting in delayed responses to serious faults such as short circuits and insulation damage, posing safety hazards.

[0004] In view of the shortcomings of the existing technologies, there is an urgent need for an AC-coupled photovoltaic-storage-charging system that is highly adaptable to the power grid, has efficient energy dispatch, and is spatially designed and highly secure. Summary of the Invention

[0005] This invention addresses the problems and shortcomings of existing technologies by providing a novel AC-coupled optical energy storage and charging integrated system and its control method.

[0006] The present invention solves the above-mentioned technical problems through the following technical solution:

[0007] This invention provides an AC-coupled photovoltaic-storage-charging integrated system, comprising an energy storage module, a photovoltaic module, a charging pile module, a power distribution module, and a control module;

[0008] The energy storage component includes an energy storage battery pack, an energy storage converter, and an energy storage controller. The energy storage controller is connected to the energy storage battery pack to control the charging or discharging of the energy storage battery pack and to acquire the status information of the energy storage battery pack. The energy storage converter has a DC terminal and an AC terminal. The energy storage battery pack is connected to the DC terminal of the energy storage converter, and the AC terminal of the energy storage converter is connected to the busbar distribution component.

[0009] The photovoltaic module includes a photovoltaic array and a photovoltaic inverter. The photovoltaic inverter has a DC input terminal and an AC output terminal. The photovoltaic array is connected to the DC input terminal of the photovoltaic inverter, and the AC output terminal of the photovoltaic inverter is connected to the combiner distribution module.

[0010] The charging pile assembly includes an AC charging pile and / or a DC fast charging pile. The AC charging pile is connected to the busbar distribution assembly, and the DC fast charging pile has a built-in AC-DC converter assembly and is connected to the busbar distribution assembly through the AC-DC converter assembly.

[0011] The power distribution assembly includes multiple AC circuit breakers and an AC coupling bus. The AC terminal of the energy storage converter, the AC output terminal of the photovoltaic inverter, and the charging pile assembly are respectively connected to the AC coupling bus through AC circuit breakers. The AC coupling bus is connected to the power grid through AC circuit breakers.

[0012] The control components include an industrial computer, a switch, and a serial port server. The industrial computer communicates with the energy storage controller, the energy storage converter, and the photovoltaic inverter through the switch and the serial port server to exchange data.

[0013] The industrial control computer controls the operation of the photovoltaic inverter, the energy storage converter, the energy storage controller, and the charging pile components based on the load status of the charging pile components, the power generation status of the photovoltaic array, the status of the energy storage battery pack, and the grid status, and schedules the flow and magnitude of photovoltaic array power, energy storage battery pack power, and grid power in real time.

[0014] Preferably, the photovoltaic inverter has a built-in MPPT module, and the photovoltaic array converts DC power into AC power through the photovoltaic inverter. After tracking the maximum power via the MPPT module, the power is delivered to the AC coupling bus.

[0015] Preferably, the control component further includes an I / O module, which is connected to the switch for data interaction. The output node of the I / O module is connected to control the closing and opening of multiple AC circuit breakers. The auxiliary contacts of the multiple AC circuit breakers are connected to the input node of the I / O module to provide feedback on the status of the AC circuit breakers.

[0016] Preferably, the energy storage battery pack includes multiple battery clusters, each battery cluster is provided with a high-voltage box and connected to a corresponding energy storage converter, the energy storage controller is correspondingly disposed in the high-voltage box, each battery cluster includes multiple battery packs, and the energy storage controller is correspondingly connected to multiple battery packs to obtain battery pack information.

[0017] Preferably, the busbar distribution assembly further includes multiple meters, which are correspondingly installed at the input terminals of multiple AC circuit breakers to measure the voltage, current and power flowing through the corresponding AC circuit breaker.

[0018] Based on the same concept, the present invention also provides a control method for the above-mentioned AC-coupled optical energy storage and charging integrated system, comprising the following steps:

[0019] S1: The industrial control computer acquires the load of the charging pile components and the power generation status of the photovoltaic array, and controls the photovoltaic inverter, energy storage converter and energy storage controller according to the load of the charging pile components and the power generation status of the photovoltaic array.

[0020] S2: If the power generation of the photovoltaic array is greater than the load of the charging pile component, the power generation of the photovoltaic array is converted from DC to AC by the photovoltaic inverter to supply power to the charging pile component, and the excess power is converted from AC to DC by the energy storage converter to charge the energy storage battery pack.

[0021] S3: If the power generation of the photovoltaic array is less than the load of the charging pile component, the power generation of the photovoltaic array is converted from DC to AC by the photovoltaic inverter to supply power to the charging pile component; the part of the charging pile component with insufficient load is supplied to the charging pile component by the energy storage battery pack after being converted from DC to AC by the energy storage converter; if the charging pile component load is still insufficient, it is supplied by the grid.

[0022] S4: If the photovoltaic array is not generating electricity, the photovoltaic array will operate at low power or standby. During the off-peak period of the power grid, the power grid will charge the energy storage battery pack after AC-DC conversion through the energy storage converter, and the power grid will supply power to the charging pile components. During the peak period of the power grid, the energy storage battery pack will supply power to the charging pile components after DC-AC conversion through the energy storage converter. If the load of the charging pile components is still insufficient, the power grid will supply power again.

[0023] Preferably, step S2 further includes: the excess power supplied by the photovoltaic array to the charging pile component charges the energy storage battery pack until the remaining power of the energy storage battery pack is greater than or equal to the set full charge threshold, then the energy storage battery pack is considered fully charged, and the energy storage inverter is controlled to stop charging the energy storage battery pack; the power generation of the photovoltaic array and / or the output power of the photovoltaic inverter are controlled so that the power generation is less than or equal to the load of the charging pile component.

[0024] Preferably, steps S3 and S4 further include: when the energy storage battery pack supplies power to the charging pile component after DC-AC conversion via the energy storage converter, if the remaining power of the energy storage battery pack is less than or equal to the set discharge threshold, the energy storage battery pack stops discharging, and the portion of the charging pile component with insufficient load is supplied by the grid.

[0025] Preferably, the method further includes the following steps: when the remaining power of the energy storage battery pack is less than or equal to the set discharge threshold, if the power generation of the photovoltaic array is greater than the load of the charging pile components, the power generation of the photovoltaic array is converted from DC to AC by the photovoltaic inverter and then from AC to DC by the energy storage converter to charge the energy storage battery pack; if the power generation of the photovoltaic array is less than the load of the charging pile components, during the off-peak hours of the power grid, the power grid charges the energy storage battery pack through the AC to DC conversion of the energy storage converter; during the peak hours of the power grid, the energy storage battery pack remains in standby mode; when the remaining power of the energy storage battery pack is greater than or equal to the set full charge threshold, the energy storage converter is controlled to stop charging the energy storage battery pack.

[0026] Preferably, the method further includes the following steps: when the AC circuit breaker connected to the AC coupling bus and the power grid trips undervoltage, the power grid supply is identified as abnormal. The industrial control computer controls the energy storage converter to operate in VSG mode and limits the maximum power of the charging pile components to a set power threshold, so that the photovoltaic array and / or energy storage battery pack supply power to the charging pile components; when the power grid supply returns to normal: the AC circuit breaker connected to the AC coupling bus and the power grid automatically recovers from undervoltage trip, the AC coupling bus is reconnected to the power grid, and the industrial control computer controls the energy storage converter to return to grid-connected mode.

[0027] The positive and progressive effects of this invention are as follows:

[0028] The AC-coupled photovoltaic-storage-charging integrated system and its control method provided by this invention feature an optimized structure. Combined with the VSG mode of the energy storage converter, it achieves seamless switching between grid-connected and off-grid modes, effectively addressing abnormal situations such as grid fluctuations and momentary power outages. It provides uninterrupted power supply to charging pile loads, responding more quickly and smoothly to the grid's frequency regulation and peak shaving needs, thus enhancing grid friendliness. In off-grid mode, it can operate independently, meeting the charging needs of remote areas or during grid failures. The operation of each component is uniformly coordinated and monitored by the control component, allowing real-time viewing of operating parameters for centralized monitoring, diagnosis, and maintenance. When a fault occurs, the control component locates the fault immediately, enhancing system reliability and maintainability. The modular design allows for flexible addition or removal of photovoltaic modules, energy storage modules, and charging pile modules according to actual needs. The AC-coupled architecture requires no large-scale modification of the existing grid, allowing direct connection to the existing grid. It is compatible with different brands of photovoltaic inverters, energy storage battery packs, and charging pile modules, reducing system upgrade and modification costs.

[0029] Furthermore, the energy storage battery pack adopts a string design, with each cluster managed independently. Each cluster operates independently, and the failure of one cluster does not affect the operation of the entire system. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the structure of an AC-coupled optical energy storage and charging integrated system according to an embodiment of the present invention;

[0031] Figure 2 This is a control topology diagram of an AC-coupled optical-storage-charging integrated system according to an embodiment of the present invention;

[0032] Figure 3 This is a flowchart of the control method for an AC-coupled optical energy storage and charging integrated system according to an embodiment of the present invention. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] Please see Figure 1 and Figure 2 This embodiment provides an AC-coupled photovoltaic-storage-charging integrated system, including an energy storage component 1, a photovoltaic component 2, a charging pile component 3, a power distribution component 4, and a control component 5;

[0035] The energy storage component 1 includes an energy storage battery pack 11, an energy storage converter (PCS) 12, and an energy storage controller (BCU) 13. The energy storage controller 13 is connected to the energy storage battery pack 11 to control the charging or discharging of the energy storage battery pack 11 and to acquire the status information of the energy storage battery pack 11. The energy storage converter 12 has a DC terminal and an AC terminal. The energy storage battery pack 11 is connected to the DC terminal of the energy storage converter 12, and the AC terminal of the energy storage converter 12 is connected to the busbar distribution component 4.

[0036] The photovoltaic module 2 includes a photovoltaic array 21 and a photovoltaic inverter 22. The photovoltaic inverter 22 has a DC input terminal and an AC output terminal. The photovoltaic array 21 is connected to the DC input terminal of the photovoltaic inverter 22, and the AC output terminal of the photovoltaic inverter 22 is connected to the combiner distribution module 4.

[0037] Charging pile component 3 includes an AC charging pile and / or a DC fast charging pile. The AC charging pile is connected to the busbar distribution component 4, and the DC fast charging pile has a built-in AC-DC conversion component (not shown) and is connected to the busbar distribution component 4 through the AC-DC conversion component.

[0038] The power distribution assembly 4 includes multiple AC circuit breakers 41 and AC coupling bus 42. The AC terminal of the energy storage converter 12, the AC output terminal of the photovoltaic inverter 22 and the charging pile assembly 3 are respectively connected to the AC coupling bus 42 through the AC circuit breaker 41. The AC coupling bus 42 is connected to the power grid 6 through the AC circuit breaker 41.

[0039] The AC coupling bus 42 serves as the common AC connection point and energy exchange hub for the energy storage converter 12, photovoltaic inverter 22, charging pile module 3, and power grid 6.

[0040] Control component 5 includes industrial computer 51, switch 52 and serial server 53. Industrial computer 51 communicates with energy storage controller 13, energy storage converter 12 and photovoltaic inverter 22 through switch 52 and serial server 53 to exchange data, obtain status information or issue control commands.

[0041] The industrial control computer 51 controls the operation of the photovoltaic inverter 22, energy storage converter 12, energy storage controller 13 and charging pile component 3 according to the load status of charging pile component 3, the power generation status of photovoltaic array 21, the status of energy storage battery pack 11 and grid 6, and schedules the flow and magnitude of power of photovoltaic array 21, energy storage battery pack 11 and grid 6 in real time.

[0042] Specifically, the AC circuit breaker 41 includes an AC frame circuit breaker 411, a first AC circuit breaker 412, a second AC circuit breaker 413, a third AC circuit breaker 414, and a fourth AC circuit breaker 415; the AC terminal of the energy storage converter 12, the AC output terminal of the photovoltaic inverter 22, and the charging pile assembly 3 are respectively connected to the AC coupling bus 42 through the first AC circuit breaker 412, the second AC circuit breaker 413, the third AC circuit breaker 414, and the fourth AC circuit breaker 415; the AC coupling bus 42 is connected to the power grid 6 through the AC frame circuit breaker 411.

[0043] Specifically, the energy storage controller 13 and the energy storage inverter 12 communicate via a CAN bus, the energy storage inverter 12, the industrial computer 51, the serial server 53 and the switch 52 communicate via a LAN network, and the energy storage inverter 12, the photovoltaic inverter 22 and the serial server 53 communicate via an RS485 bus.

[0044] Specifically, the control component 5 also includes a display screen and a 4G module. Both the display screen and the 4G module are connected to the switch 52 via a LAN network for communication. The display screen is used for parameter input and display. The industrial control computer 51 communicates with the host computer and other devices via the 4G module for data interaction.

[0045] In some embodiments, the photovoltaic inverter 22 has a built-in MPPT module. The photovoltaic array 21 converts DC power into AC power through the photovoltaic inverter 22, and then transmits the power to the AC coupling bus 42 after tracking the maximum power via the MPPT module.

[0046] In some embodiments, the control component 5 further includes an IO module 54, which is connected to the switch 52 for data interaction. The output node of the IO module 54 is connected to control the closing and opening of multiple AC circuit breakers 41. The auxiliary contacts of the multiple AC circuit breakers 41 are connected to the input node of the IO module 54 to provide feedback on the status of the AC circuit breakers 41.

[0047] Specifically, the IO module 54 communicates with the switch 52 via a LAN network.

[0048] In some embodiments, the energy storage battery pack 11 includes multiple battery clusters 111, each battery cluster 111 is provided with a high-voltage box 112 and is connected to an energy storage inverter 12, and an energy storage controller 13 is provided in the high-voltage box 112. Each battery cluster 111 includes multiple battery packs, and the energy storage controller 13 is connected to multiple battery packs to obtain battery pack information, accurately understand the status of each battery pack, and accurately locate the faulty battery pack when a fault occurs.

[0049] Specifically, the energy storage controller 13 communicates with the battery pack via a CAN bus.

[0050] In some embodiments, the busbar distribution assembly 4 further includes a plurality of meters 43, which are correspondingly disposed at the input terminals of a plurality of AC circuit breakers 41 to measure the voltage, current and power flowing through the corresponding AC circuit breaker 41.

[0051] Specifically, multiple electricity meters 43 are connected to an industrial control computer 51 or a serial server 53 via an RS485 bus. The industrial control computer 51 can obtain the information of the electricity meters 43 in real time or obtain the information of the electricity meters 43 in real time through a switch 52 and a serial server 53. The load status of the charging pile component 3 can be obtained through the electricity meters 43 connected to the charging pile component 3.

[0052] Please see Figure 3 The present invention also provides a control method for an AC-coupled optical-storage-charging integrated system, comprising the following steps:

[0053] S1: The industrial control computer 51 acquires the load of the charging pile component 3 and the power generation status of the photovoltaic array 21, and controls the photovoltaic inverter 22, the energy storage converter 12 and the energy storage controller 13 according to the load of the charging pile component 3 and the power generation status of the photovoltaic array 21.

[0054] S2: If the power generation of the photovoltaic array 21 is greater than the load of the charging pile component 3, the power generation of the photovoltaic array 21 is converted from DC to AC by the photovoltaic inverter 22 to supply power to the charging pile component 3, and the excess power is converted from AC to DC by the energy storage converter 12 to charge the energy storage battery pack 11.

[0055] S3: If the power generation of the photovoltaic array 21 is less than the load of the charging pile component 3, the power generation of the photovoltaic array 21 is converted from DC to AC by the photovoltaic inverter 22 to supply power to the charging pile component 3; the part of the charging pile component 3 that is not fully loaded is supplied to the charging pile component 3 by the energy storage battery pack 11 after being converted from DC to AC by the energy storage converter 12; if the load of the charging pile component 3 is still not fully loaded, it is supplied by the grid 6.

[0056] S4: If the photovoltaic array 21 is not generating electricity, the photovoltaic array 21 operates at low power or is in standby mode; during the off-peak hours of the power grid 6, the power grid 6 charges the energy storage battery pack 11 through the AC-DC conversion of the energy storage converter 12, and the power grid 6 supplies power to the charging pile component 3; during the peak hours of the power grid 6, the energy storage battery pack 11 supplies power to the charging pile component 3 through the DC-AC conversion of the energy storage converter 12; if the load of the charging pile component 3 is still insufficient, the power grid 6 supplies power again.

[0057] In some embodiments, step S2 further includes: the excess power supplied by the photovoltaic array 21 to the charging pile component 3 charges the energy storage battery pack 11 until the remaining power of the energy storage battery pack 11 is greater than or equal to a set full charge threshold, then the energy storage battery pack 11 is considered fully charged, and the energy storage inverter 12 is controlled to stop charging the energy storage battery pack 11; the power generation of the photovoltaic array 21 and / or the output power of the photovoltaic inverter 22 are controlled so that the power generation is less than or equal to the load of the charging pile component 3.

[0058] In some embodiments, steps S3 and S4 further include: when the energy storage battery pack 11 supplies power to the charging pile assembly 3 after DC-AC conversion via the energy storage converter 12, if the remaining power of the energy storage battery pack 11 is less than or equal to the set discharge threshold, the energy storage battery pack 11 stops discharging, and the portion of the charging pile assembly 3 with insufficient load is supplied by the power grid 6.

[0059] In some embodiments, the following steps are also included: when the remaining power of the energy storage battery pack 11 is less than or equal to a set discharge threshold, if the power generation of the photovoltaic array 21 is greater than the load of the charging pile component 3, the power generation of the photovoltaic array 21 is converted from DC to AC by the photovoltaic inverter 22 and then converted from AC to DC by the energy storage converter 12 to charge the energy storage battery pack 11; if the power generation of the photovoltaic array 21 is less than the load of the charging pile component 3, during the low-consumption period of the power grid 6, the power grid 6 charges the energy storage battery pack 11 through the energy storage converter 12 after AC to DC conversion; during the peak-consumption period of the power grid 6, the energy storage battery pack 11 remains in its current standby state; when the remaining power of the energy storage battery pack 11 is greater than or equal to a set full-charge threshold, the energy storage converter 12 is controlled to stop charging the energy storage battery pack 11.

[0060] In some embodiments, the following steps are also included: when the AC circuit breaker 41 (AC frame circuit breaker 411) connected to the AC coupling bus 42 and the power grid 6 trips due to undervoltage, the power supply of the power grid 6 is identified as abnormal. The industrial control computer 51 controls the energy storage converter 12 to operate in VSG (Virtual Synchronous Generator) mode and limits the maximum power of the charging pile component 3 to a set power threshold, so that the photovoltaic array 21 and / or the energy storage battery pack 11 supply power to the charging pile component 3; when the power grid power supply returns to normal: the AC circuit breaker 41 connected to the AC coupling bus 42 and the power grid 6 automatically recovers from undervoltage trip, the AC coupling bus 42 is restored to the connection with the power grid 6, and the industrial control computer controls the energy storage converter 12 to resume grid-connected mode.

[0061] In summary, the AC-coupled photovoltaic-storage-charging integrated system and its control method provided by this invention, with optimized structure and VSG mode of energy storage inverter 12, achieve seamless switching between grid-connected and off-grid modes. It can effectively cope with abnormal situations such as grid fluctuations and instantaneous power outages, providing uninterrupted power supply to charging pile loads, and responding to the grid's frequency regulation and peak shaving needs more quickly and smoothly, thus enhancing grid friendliness. In off-grid mode, it can operate independently to meet the charging needs of remote areas or grid failures. The operation status of each component is uniformly coordinated and monitored by control component 5, allowing real-time viewing of operating parameters for centralized monitoring, diagnosis, and maintenance. When a fault occurs, control component 5 locates the fault immediately, enhancing system reliability and maintainability. The modular design allows for flexible addition or removal of photovoltaic module 2, energy storage module 1, and charging pile module 3 according to actual needs. The AC-coupled architecture does not require large-scale modification of the existing grid 6 and can be directly connected to the existing grid 6, compatible with photovoltaic inverters 22, energy storage battery packs 11, and charging pile modules 3 from different brands, reducing system upgrade and modification costs.

[0062] Furthermore, the energy storage battery pack 11 adopts a string design, with each cluster managed independently. When one cluster fails, it does not affect the operation of the entire system.

[0063] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but all such changes and modifications fall within the scope of protection of the present invention.

Claims

1. An AC-coupled optical energy storage and charging integrated system, characterized in that, This includes energy storage modules, photovoltaic modules, charging pile modules, power distribution modules, and control modules; The energy storage component includes an energy storage battery pack, an energy storage converter, and an energy storage controller. The energy storage controller is connected to the energy storage battery pack to control the charging or discharging of the energy storage battery pack and to acquire the status information of the energy storage battery pack. The energy storage converter has a DC terminal and an AC terminal. The energy storage battery pack is connected to the DC terminal of the energy storage converter, and the AC terminal of the energy storage converter is connected to the busbar distribution component. The photovoltaic module includes a photovoltaic array and a photovoltaic inverter. The photovoltaic inverter has a DC input terminal and an AC output terminal. The photovoltaic array is connected to the DC input terminal of the photovoltaic inverter, and the AC output terminal of the photovoltaic inverter is connected to the combiner distribution module. The charging pile assembly includes an AC charging pile and / or a DC fast charging pile. The AC charging pile is connected to the busbar distribution assembly, and the DC fast charging pile has a built-in AC-DC converter assembly and is connected to the busbar distribution assembly through the AC-DC converter assembly. The power distribution assembly includes multiple AC circuit breakers and an AC coupling bus. The AC terminal of the energy storage converter, the AC output terminal of the photovoltaic inverter, and the charging pile assembly are respectively connected to the AC coupling bus through AC circuit breakers. The AC coupling bus is connected to the power grid through AC circuit breakers. The control components include an industrial computer, a switch, and a serial port server. The industrial computer communicates with the energy storage controller, the energy storage converter, and the photovoltaic inverter through the switch and the serial port server to exchange data. The industrial control computer controls the operation of the photovoltaic inverter, the energy storage converter, the energy storage controller, and the charging pile components based on the load status of the charging pile components, the power generation status of the photovoltaic array, the status of the energy storage battery pack, and the grid status, and schedules the flow and magnitude of photovoltaic array power, energy storage battery pack power, and grid power in real time.

2. The AC-coupled optical storage and charging integrated system as described in claim 1, characterized in that, The photovoltaic inverter has a built-in MPPT module. The photovoltaic array converts DC power into AC power through the photovoltaic inverter, and then transmits the power to the AC coupling bus after tracking the maximum power via the MPPT module.

3. The AC-coupled optical storage and charging integrated system as described in claim 1, characterized in that, The control component also includes an I / O module, which is connected to the switch for data interaction. The output node of the I / O module is connected to control the closing and opening of multiple AC circuit breakers. The auxiliary contacts of the multiple AC circuit breakers are connected to the input node of the I / O module to provide feedback on the status of the AC circuit breakers.

4. The AC-coupled optical storage and charging integrated system as described in claim 1, characterized in that, The energy storage battery pack includes multiple battery clusters, each battery cluster is provided with a high-voltage box and connected to a corresponding energy storage converter, and the energy storage controller is located in the high-voltage box. Each battery cluster includes multiple battery packs, and the energy storage controller is connected to multiple battery packs to obtain battery pack information.

5. The AC-coupled optical storage and charging integrated system as described in claim 1, characterized in that, The power distribution assembly also includes multiple meters, which are correspondingly installed at the input terminals of multiple AC circuit breakers to measure the voltage, current and power flowing through the corresponding AC circuit breaker.

6. A control method for an AC-coupled optical-storage-charging integrated system as described in any one of claims 1-5, characterized in that, Includes the following steps: S1: The industrial control computer acquires the load of the charging pile components and the power generation status of the photovoltaic array, and controls the photovoltaic inverter, energy storage converter and energy storage controller according to the load of the charging pile components and the power generation status of the photovoltaic array. S2: If the power generation of the photovoltaic array is greater than the load of the charging pile component, the power generation of the photovoltaic array is converted from DC to AC by the photovoltaic inverter to supply power to the charging pile component, and the excess power is converted from AC to DC by the energy storage converter to charge the energy storage battery pack. S3: If the power generation of the photovoltaic array is less than the load of the charging pile component, the power generation of the photovoltaic array is converted from DC to AC by the photovoltaic inverter to supply power to the charging pile component; the part of the charging pile component with insufficient load is supplied to the charging pile component by the energy storage battery pack after being converted from DC to AC by the energy storage converter; if the charging pile component load is still insufficient, it is supplied by the grid. S4: If the photovoltaic array is not generating electricity, the photovoltaic array will operate at low power or standby. During the off-peak period of the power grid, the power grid will charge the energy storage battery pack after AC-DC conversion through the energy storage converter, and the power grid will supply power to the charging pile components. During the peak period of the power grid, the energy storage battery pack will supply power to the charging pile components after DC-AC conversion through the energy storage converter. If the load of the charging pile components is still insufficient, the power grid will supply power again.

7. The control method for the AC-coupled optical-storage-charging integrated system as described in claim 6, characterized in that, Step S2 further includes: the excess power supplied by the photovoltaic array to the charging pile component charges the energy storage battery pack until the remaining power of the energy storage battery pack is greater than or equal to the set full charge threshold, then the energy storage battery pack is considered to be fully charged, and the energy storage inverter is controlled to stop charging the energy storage battery pack; the power generation of the photovoltaic array and / or the output power of the photovoltaic inverter are controlled so that the power generation is less than or equal to the load of the charging pile component.

8. The control method for the AC-coupled optical-storage-charging integrated system as described in claim 6, characterized in that, Steps S3 and S4 further include: when the energy storage battery pack supplies power to the charging pile component after DC-AC conversion via the energy storage converter, if the remaining power of the energy storage battery pack is less than or equal to the set discharge threshold, the energy storage battery pack stops discharging, and the portion of the charging pile component with insufficient load is supplied by the grid.

9. The control method for the AC-coupled optical-storage-charging integrated system as described in claim 6, characterized in that, The process also includes the following steps: When the remaining power of the energy storage battery pack is less than or equal to the set discharge threshold, if the power generation of the photovoltaic array is greater than the load of the charging pile components, the power generation of the photovoltaic array is converted from DC to AC by the photovoltaic inverter and then from AC to DC by the energy storage converter to charge the energy storage battery pack; if the power generation of the photovoltaic array is less than the load of the charging pile components, during the off-peak hours of the power grid, the power grid charges the energy storage battery pack through the AC to DC conversion of the energy storage converter; during the peak hours of the power grid, the energy storage battery pack remains in standby mode; when the remaining power of the energy storage battery pack is greater than or equal to the set full charge threshold, the energy storage converter is controlled to stop charging the energy storage battery pack.

10. The control method for the AC-coupled photovoltaic-energy storage-charging integrated system as described in claim 6, characterized in that, The process also includes the following steps: when the AC circuit breaker connected to the AC coupling bus and the power grid trips undervoltage, the power grid supply is identified as abnormal. The industrial control computer controls the energy storage converter to operate in VSG mode and limits the maximum power of the charging pile components to a set power threshold. The photovoltaic array and / or energy storage battery pack then supply power to the charging pile components. When the power grid supply returns to normal: the AC circuit breaker connected to the AC coupling bus and the power grid automatically recovers from undervoltage tripping, the AC coupling bus is reconnected to the power grid, and the industrial control computer controls the energy storage converter to return to grid-connected mode.

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