Control system of energy storage system, control method thereof and energy storage system

Abstract

An energy storage system (100), a control system (200) and a control method (300) of the energy storage system (100), the energy storage system (100) comprising a converter valve (110) and an energy storage valve (120), the energy storage valve (120) being connected to a direct current side of the converter valve (110), the control system (200) comprising: a coordination control subsystem (210), a converter valve control subsystem (220) and an energy storage valve control subsystem (230). The coordination control subsystem (210) is used for sending instructions to control the converter valve control subsystem (220) and the energy storage valve control subsystem (230) to work. And the converter valve control subsystem (220) is used for controlling the converter valve (110) to work according to the instruction of the coordination control subsystem (210). And the energy storage valve control subsystem (230) is used for controlling the energy storage valve (120) to work according to the instruction of the coordination control subsystem (210). The control system (200) of the energy storage system (100) can realize cooperative control between the converter valve (110) and the energy storage valve (120).

Description

Energy storage system control system and control method thereof and energy storage system Technical Field

[0001] The present application relates to the technical field of power system energy storage, and in particular to a control system of an energy storage system, a control method thereof, and an energy storage system. Background Art

[0002] In the field of power system energy storage technology, the new energy storage technology integrates the converter valve and the energy storage valve, which has the advantages of high modularity, low system network loss, good economic benefits and high operational reliability.

[0003] Currently, the control architecture of new energy storage systems has not been studied.

[0004] Summary of the Invention

[0005] In view of this, an embodiment of the present application provides a control system of an energy storage system, a control method thereof, and an energy storage system, which can achieve coordinated control between a converter valve and an energy storage valve.

[0006] In a first aspect, a control system for an energy storage system is provided, wherein the energy storage system includes a converter valve and an energy storage valve, wherein the energy storage valve is connected to the DC side of the converter valve, and the control system includes: a coordination control subsystem, a converter valve control subsystem, and an energy storage valve control subsystem; the coordination control subsystem is used to send instructions to control the operation of the converter valve control subsystem and the energy storage valve control subsystem; the converter valve control subsystem is used to control the operation of the converter valve according to the instructions of the coordination control subsystem; and the energy storage valve control subsystem is used to control the operation of the energy storage valve according to the instructions of the coordination control subsystem.

[0007] In this embodiment, the coordinated control subsystem controls the operation of the converter valve control subsystem and the energy storage valve control subsystem, thereby achieving coordinated control between the converter valve and the energy storage valve.

[0008] In one possible implementation, the converter valve includes N first power modules, and the converter valve control subsystem includes a converter valve control unit and N first power control units, where N is a positive integer; the converter valve control unit is used to generate K first control instructions for the N first power modules according to the instructions of the coordinated control subsystem, where K is a positive integer less than or equal to N; and the N first power control units are used to control the input or output of the N first power modules respectively according to the K first control instructions.

[0009] In this embodiment, a converter valve control unit and N first power control units are provided for the N first power modules in the converter valve, and the converter valve control unit serves as an upper-level control unit of the N first power control units to communicate with the coordinated control subsystem. That is, the converter valve control subsystem adopts a hierarchical design and a modular design, which is easy to expand and integrate.

[0010] In a possible implementation, each of the N first power control units is further configured to upload status information of the corresponding first power module to the converter valve control unit.

[0011] In this embodiment, the first power control unit uploads the status information of the first power modules to the converter valve control unit, which helps the converter valve control unit to timely understand the status of each first power module, thereby ensuring the reliability of system control.

[0012] In a possible implementation, the converter valve control unit is further configured to upload valve control status information of the converter valve to the coordinated control subsystem.

[0013] In this embodiment, the valve control status information of the converter valve is uploaded to the coordinated control subsystem through the converter valve control unit, which helps the coordinated control subsystem to timely understand the status of the converter valve, so as to better coordinate and control the operation of the converter valve and the energy storage valve, thereby ensuring the reliability of system control.

[0014] In one possible implementation, the energy storage valve includes M energy storage modules, each of the M energy storage modules includes a second power module and a battery module, and the energy storage valve control subsystem includes an energy storage valve control unit, M second power control units, and M battery control units, where M is a positive integer; the energy storage valve control unit is used to generate Q second control instructions for the M second power modules in the M energy storage modules according to instructions of the coordinated control subsystem, where Q is a positive integer less than or equal to M; the M second power control units are used to control the input or output of the M second power modules respectively according to the Q second control instructions; and the M battery control units are used to respectively control the charging and discharging of the M battery modules in the M energy storage modules.

[0015] In this embodiment, an energy storage valve control unit, M second power control units, and M battery control units are provided for the M second power modules and M battery modules in the energy storage valve. The energy storage valve control unit serves as the upper-level control unit for the M second power control units and communicates with the coordinated control subsystem. This means that the energy storage valve control subsystem adopts a layered and modular design, making it easy to expand and integrate. Furthermore, the converter valve and energy storage generator are controlled separately, and the converter valve control subsystem technology is relatively mature. The energy storage valve control subsystem can be expanded and developed based on the converter valve control subsystem, facilitating engineering implementation.

[0016] In one possible implementation, the energy storage valve control unit is also used to generate P third control instructions for the M battery modules according to the instructions of the coordinated control subsystem, where P is a positive integer less than or equal to M; the M battery control units are used to control the charging and discharging of the M battery modules respectively according to the P third control instructions.

[0017] In this embodiment, the M battery control units can communicate directly with the energy storage valve control unit, which is conducive to the second power control unit and the battery control unit controlling the second power module and the battery module in parallel, thereby improving the control efficiency of the system.

[0018] In a possible implementation, each of the M battery control units is further configured to upload status information of the corresponding battery module to the energy storage valve control unit.

[0019] In this embodiment, the battery control unit uploads the status information of the corresponding battery module to the energy storage valve control unit, so that the energy storage valve control unit can timely understand the status of the battery module and perform corresponding control on the battery module, thereby ensuring the control reliability of the energy storage valve control subsystem.

[0020] In one possible implementation, the M second power control units are also used to generate R fourth control instructions for the M battery modules according to the Q second control instructions, where R is a positive integer less than or equal to M; the M battery control units are used to control the charging and discharging of the M battery modules according to the R fourth control instructions.

[0021] In this embodiment, the M battery control units are respectively controlled by the M second power control units, which can reduce the communication load of the energy storage valve control unit.

[0022] In a possible implementation, each of the M battery control units is further configured to upload status information of the corresponding battery module to the corresponding second power control unit.

[0023] In this embodiment, the battery control unit uploads the status information of the corresponding battery module to the second power control unit, so that the second power control unit can promptly feedback the status of the battery module to the energy storage valve control unit and perform corresponding control on the battery module, thereby ensuring the control reliability of the energy storage valve control subsystem.

[0024] In a possible implementation, the energy storage valve control unit is further configured to upload valve control state information of the energy storage valve to the coordinated control subsystem.

[0025] In this embodiment, the valve control status information of the energy storage valve is uploaded to the coordinated control subsystem through the energy storage valve control unit, which helps the coordinated control subsystem to timely understand the status of the energy storage valve, so as to better coordinate and control the operation of the energy storage valve and the energy storage valve, thereby ensuring the reliability of system control.

[0026] In a possible implementation, each of the M second power control units is further configured to upload status information of the corresponding second power module to the energy storage valve control unit.

[0027] In this embodiment, the second power control unit uploads the status information of the second power modules to the energy storage valve control unit, which helps the energy storage valve control unit to timely understand the status of each second power module, thereby ensuring the reliability of system control.

[0028] In a possible implementation, the second power control unit and the battery control unit corresponding to the same energy storage module communicate with each other.

[0029] In a possible implementation, the energy storage valve control subsystem further includes: a battery monitoring unit, configured to obtain battery data of the M battery modules.

[0030] In a possible implementation, M is a positive integer greater than 1, and the M battery control units are connected in daisy chain communication.

[0031] In a possible implementation, the converter valve control subsystem includes multiple converter valve control units, each of the multiple converter valve control units communicates with the N first power control units, and the multiple converter valve control units communicate with each other.

[0032] In this embodiment, the converter valve control subsystem includes multiple converter valve control units, and the multiple converter valve control units communicate with each other and communicate with N first power control units, which can meet the redundant design requirements of the converter valve control subsystem and ensure the control reliability of the converter valve control subsystem.

[0033] In a possible implementation, the energy storage valve control subsystem includes multiple energy storage valve control units, each of the multiple energy storage valve control units communicates with the M second power control units, and the multiple energy storage valve control units communicate with each other.

[0034] In this embodiment, the energy storage valve control subsystem includes multiple energy storage valve control units, and the multiple energy storage valve control units communicate with each other and communicate with M second power control units, which can meet the redundant design requirements of the energy storage valve control subsystem and ensure the control reliability of the energy storage valve control subsystem.

[0035] In a possible implementation, the coordinated control subsystem includes multiple system control units, each of the multiple system control units communicates with the converter valve control subsystem and the energy storage valve control subsystem, and the multiple system control units communicate with each other.

[0036] In this embodiment, the coordinated control subsystem includes multiple system control units, and the multiple system control units communicate with each other and communicate with the converter valve control subsystem and the energy storage valve control subsystem, which can meet the redundant design requirements of the coordinated control subsystem and ensure the control reliability of the coordinated control subsystem.

[0037] In a possible implementation, the converter valve control subsystem is integrated into the converter valve, and the energy storage valve control subsystem is integrated into the energy storage valve.

[0038] In a second aspect, an energy storage system is provided, comprising a converter valve and an energy storage valve, wherein the energy storage valve is connected to the DC side of the converter valve. The energy storage system further comprises a control system as in the first aspect and any possible implementation thereof.

[0039] In a third aspect, a control method for an energy storage system is provided, wherein the energy storage system includes a converter valve and an energy storage valve, wherein the energy storage valve is connected to the DC side of the converter valve. The control method includes: sending a first instruction to the converter valve control subsystem and sending a second instruction to the energy storage valve control subsystem, wherein the first instruction is used to control the operation of the converter valve, and the second instruction is used to control the operation of the energy storage valve.

[0040] In a fourth aspect, a computer-readable storage medium is provided, characterized in that it is used to store a computer program, which enables a computer to execute the method in the first aspect and any possible implementation of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the drawings without creative work.

[0042] FIG1 shows a schematic architecture diagram of a high-voltage direct current (HVDC) energy storage system applicable to an embodiment of the present application.

[0043] FIG2 shows a schematic structural diagram of the VSC converter valve in FIG1 .

[0044] FIG3 shows a schematic structural diagram of the DC energy storage valve in FIG1 .

[0045] FIG4 a shows a schematic structural diagram of the energy storage module in FIG3 .

[0046] FIG4 b shows another schematic structural diagram of the energy storage module in FIG3 .

[0047] FIG5 shows a schematic architecture diagram of a control system provided in an embodiment of the present application.

[0048] FIG6 shows a schematic block diagram of a converter valve control subsystem in the control system in FIG5 .

[0049] FIG. 7 shows a schematic block diagram of an energy storage valve control subsystem in the control system in FIG. 5 .

[0050] FIG8 shows another schematic architecture diagram of a control system provided in an embodiment of the present application.

[0051] FIG9 shows another schematic architecture diagram of the control system provided in an embodiment of the present application.

[0052] FIG10 shows a schematic block diagram of a control method provided in an embodiment of the present application.

[0053] FIG11 shows a schematic flow chart of a control method for an energy storage system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0054] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0055] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first" and "second" in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0056] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0057] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "connected" and "connected" may refer to direct connection, indirect connection through an intermediate medium, or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0058] The term "and / or" in this application simply describes an association between related objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0059] In the field of power system energy storage, new energy storage technologies integrate converter valves with energy storage valves, offering advantages such as high modularity, low system losses, good economic benefits, and high operational reliability. For example, by integrating energy storage valves on the DC side of a voltage source converter (VSC) converter valve, AC / DC power conversion and energy storage can be achieved simultaneously. Compared to traditional energy storage technologies, these new energy storage systems offer higher voltage levels, larger capacities, and enhanced grid regulation and support capabilities, making them of great research significance for new power systems dominated by renewable energy.

[0060] Currently, the control architecture of new energy storage systems has not been studied.

[0061] In view of this, an embodiment of the present application provides a control system for an energy storage system, which can achieve coordinated control between the converter valve and the energy storage valve through a coordinated control subsystem.

[0062] Figure 1 shows a schematic architecture diagram of a high-voltage direct current (HVDC) energy storage system applicable to embodiments of the present application. As shown in Figure 1 , the HVDC energy storage system 100 includes a VSC converter valve 110 and an energy storage valve 120 . The energy storage valve 120 is connected to the DC side of the VSC converter valve 110 . Optionally, the VSC converter valve 110 may employ an MMC structure as shown in Figure 2 . Specifically, as shown in Figure 2 , the VSC converter valve 110 may include six bridge arms, with two bridge arms connected in series. Each bridge arm includes n power modules (111_1, 111_2, ..., 111_n). As shown in Figure 3 , the energy storage valve 120 includes m series-connected energy storage modules 121 (121_1, 121_2, ..., 121_m-1, 121_m). Each energy storage module 121 may be composed of a power module 1211 connected to a battery module 1212. Specifically, the power module 1211 can be a half-bridge power module as shown in Figure 4a, or a full-bridge power module as shown in Figure 4b. The battery module 1212 can be a single-branch series battery module, a multi-branch parallel battery module, or a series-parallel battery module.

[0063] It should be noted that the control system of the energy storage system provided in the embodiment of the present application is not only applicable to the high-voltage direct-connected energy storage system 100 shown in Figure 1, but can also be applied to other energy storage systems, for example, high-voltage alternating current direct-connected energy storage systems, and the embodiment of the present application is not limited to this.

[0064] Figure 5 shows a schematic block diagram of a control system 200 for an energy storage system according to an embodiment of the present application. Optionally, the energy storage system may be the HVDC direct-connected energy storage system 100 described in Figure 1 . The energy storage system may include a converter valve and an energy storage valve, with the energy storage valve connected to the DC side of the converter valve. For example, the energy storage valve may be connected in parallel to the DC side of the converter valve. As shown in Figure 5 , the control system 200 may include a coordination control subsystem 210, a converter valve control subsystem 220, and an energy storage valve control subsystem 230. The coordination control subsystem 210 is configured to send instructions to control the operation of the converter valve control subsystem 220 and the energy storage valve control subsystem 230; the converter valve control subsystem 220 is configured to control the operation of the converter valve according to the instructions of the coordination control subsystem 210; and the energy storage valve control subsystem 230 is configured to control the operation of the energy storage valve according to the instructions of the coordination control subsystem 210.

[0065] Specifically, the coordinated control subsystem 210 may be responsible for receiving instructions from the upper-level control system of the control system 200 and, based on the instructions from the upper-level control system, coordinating and controlling the operations of the converter valve control subsystem 220 and the energy storage valve control subsystem 230. In other words, the coordinated control subsystem 210 communicates with the converter valve control subsystem 220 and the energy storage valve control subsystem 230, respectively. For example, the coordinated control subsystem 210 may issue instructions to the converter valve control subsystem 220 to control the operation of the converter valve; the coordinated control subsystem 210 may also issue instructions to the energy storage valve control subsystem 230 to control the operation of the energy storage valve.

[0066] In this embodiment, the coordinated control subsystem 210 controls the operation of the converter valve control subsystem 220 and the energy storage valve control subsystem 230, thereby achieving coordinated control between the converter valve and the energy storage valve.

[0067] Optionally, in an embodiment of the present application, the converter valve includes N first power modules. Furthermore, as shown in Figure 6 , the converter valve control subsystem 220 includes a converter valve control unit 221 and N first power control units 222 , where N is a positive integer. The converter valve control unit 221 is configured to generate K first control instructions for the N first power modules based on instructions from the coordination control subsystem 210 , where K is a positive integer less than or equal to N. The N first power control units 222 are configured to control the switching on or off of the N first power modules, respectively, based on the K first control instructions.

[0068] Specifically, the converter valve includes N first power modules, which may be the power module 111 shown in Figure 2 . In one example, the first power module may be the half-bridge power module 1211 shown in Figure 4a . In another example, the first power module may be the full-bridge power module 1211 shown in Figure 4b . Optionally, the converter valve control subsystem 220 may include a converter valve control unit 221 and N first power control units 222 . That is, each of the N first power modules corresponds to a first power control unit 222 , and the N first power control units 222 correspond to a common converter valve control unit 221 . The converter valve control unit 221 is responsible for receiving instructions from the coordinated control subsystem 210 and generating control instructions for the K first power modules. In one example, K is equal to N, i.e., each first power module corresponds to a control instruction, and each first power control unit 222 corresponds to a control instruction. Each first power control unit 222 of the N first power control units 222 is responsible for receiving the corresponding control instruction generated by the converter valve control unit 221 and controlling the operation of the corresponding first power module, for example, controlling the corresponding first power module to be switched on or off. In another example, K is less than N, i.e., only some of the N first power control units 222 receive the control instruction. These first power control units 222 can control the operation of the corresponding first power module according to the received control instruction, for example, controlling the corresponding first power module to be switched on or off, while the other first power control units 222 that do not receive the control instruction can control the corresponding first power module to be in a default state, for example, a default switch-off state or a default switched-on state.

[0069] In this embodiment, a converter valve control unit 221 and N first power control units 222 are provided for the N first power modules in the converter valve, and the converter valve control unit 221 serves as an upper-level control unit of the N first power control units 222 to communicate with the coordination control subsystem 210, that is, the converter valve control subsystem 220 adopts a hierarchical design and a modular design, which is easy to expand and integrate.

[0070] Optionally, in the embodiment of the present application, each first power control unit 222 of the N first power control units 222 is further configured to upload status information of the corresponding first power module to the converter valve control unit 221 .

[0071] Optionally, the status information of the first power module primarily includes states such as on, off, locked, and fault. That is, the status information of the first power module is used to indicate to the converter valve control unit 221 whether the corresponding first power module is currently in the on, off, locked, or fault state. Furthermore, if the first power module is in a faulty state, the status information of the first power module is also used to indicate to the converter valve control unit 221 the current fault of the corresponding first power module.

[0072] In this embodiment, the status information of the first power modules is uploaded to the converter valve control unit 221 by the first power control unit 222, which helps the converter valve control unit 221 to timely understand the status of each first power module, thereby ensuring the reliability of system control.

[0073] Optionally, in the embodiment of the present application, the converter valve control unit 221 is further configured to upload valve control status information of the converter valve to the coordinated control subsystem 210 .

[0074] Optionally, the valve control state information of the converter valve primarily includes three states: locked, faulty, or operational. In other words, the valve control state information is used to indicate to the coordinated control subsystem 210 whether the converter valve is currently locked, faulty, or operational. Furthermore, if the converter valve is in a faulty state, the valve control state information of the converter valve is also used to indicate to the coordinated control subsystem 210 the current fault.

[0075] Optionally, the converter valve control unit 221 may also determine the valve control status information of the converter valve based on the status information of the N first power modules reported by the N first power control units 222, and then report the determined valve control status information to the coordinated control subsystem 210.

[0076] In this embodiment, the valve control status information of the converter valve is uploaded to the coordinated control subsystem 210 through the converter valve control unit 221, which helps the coordinated control subsystem 210 to timely understand the status of the converter valve, so as to better coordinate and control the operation of the converter valve and the energy storage valve, thereby ensuring the reliability of system control.

[0077] Optionally, in an embodiment of the present application, the converter valve control subsystem 220 includes multiple converter valve control units 221, each of the multiple converter valve control units 221 communicates with N first power control units 222, and the multiple converter valve control units 221 communicate with each other.

[0078] Optionally, the multiple valve control units 221 can communicate with each other, exchange control information, and switch between master and slave modes. That is, one of the multiple valve control units 221 is the master control unit, while the remaining valve control units 221 are slave control units. If the master control unit fails, one of the slave control units can be set as the master control unit.

[0079] It should be understood that the multiple converter valve control units 221 can be integrated into different plug-ins within the same device, or can be set in different devices; similarly, the N first power control units 222 can be integrated into different plug-ins within the same device, or can be set in different devices; in addition, the converter valve control unit 221 can be integrated with the first power control unit 222 in different plug-ins within the same device, or can be set in different devices, and the embodiments of the present application are not limited to this.

[0080] In this embodiment, the converter valve control subsystem 220 includes multiple converter valve control units 221, and the multiple converter valve control units 221 communicate with each other and communicate with N first power control units 222, which can meet the redundant design requirements of the converter valve control subsystem 220 and ensure the control reliability of the converter valve control subsystem 220.

[0081] Optionally, in an embodiment of the present application, the energy storage valve includes M energy storage modules, each of the M energy storage modules includes a second power module and a battery module, and M is a positive integer. Further, as shown in Figure 7, the energy storage valve control subsystem 230 includes an energy storage valve control unit 231, M second power control units 232, and M battery control units 233. The energy storage valve control unit 231 is used to generate Q second control instructions for the M second power modules in the M energy storage modules according to the instructions of the coordination control subsystem 210, where Q is a positive integer less than or equal to M; the M second power control units 232 are used to control the input or output of the M second power modules according to the Q second control instructions; and the M battery control units 233 are used to control the charge and discharge of the M battery modules in the M energy storage modules.

[0082] Specifically, the energy storage valve includes M energy storage modules, each of which may be the energy storage module 121 shown in FIG3 , and each of which includes a second power module and a battery module connected in parallel. That is, the energy storage valve includes M second power modules and M battery modules. In one example, the second power module may be a half-bridge power module 1211 as shown in FIG4a . In another example, the second power module may also be a full-bridge power module 1211 as shown in FIG4b . Optionally, the energy storage valve control subsystem 230 may include an energy storage valve control unit 231 , M second power control units 232 , and M battery control units 233 . That is, each of the M second power modules corresponds to a second power control unit 232 , each of the M battery modules corresponds to a battery control unit 233 , and the M second power control units 232 and the M battery control units 233 correspond to a common energy storage valve control unit 231 . The energy storage valve control unit 231 is responsible for receiving instructions from the coordinated control subsystem 210 and generating control instructions for Q second power modules. In one example, Q is equal to M, i.e., each second power module corresponds to a control instruction, and each second power control unit 232 corresponds to a control instruction. Each second power control unit 232 in the M second power control units 232 is responsible for receiving the corresponding control instruction generated by the energy storage valve control unit 231 and controlling the operation of the corresponding second power module, for example, controlling the corresponding second power module to be switched on or off. In another example, Q is less than M, i.e., only some of the M second power control units 232 receive control instructions. These second power control units 232 can control the operation of the corresponding second power module according to the received control instructions, for example, controlling the corresponding second power module to be switched on or off, while the remaining second power control units 232 that do not receive control instructions can control the corresponding second power module to a default state, for example, a default switched-off state or a default switched-on state. In addition, each battery control unit 233 in the M battery control units 233 is used to control the operation of the corresponding battery module, for example, to control the charging and discharging of the corresponding battery module.

[0083] In this embodiment, energy storage valve control units 231, M second power control units 232, and M battery control units 233 are provided for the M second power modules and M battery modules in the energy storage valve. Energy storage valve control unit 231 serves as the upper-level control unit for the M second power control units 232, communicating with coordination control subsystem 210. This means that energy storage valve control subsystem 230 employs a layered and modular design, facilitating expansion and integration. Furthermore, the converter valve and energy storage generator are controlled separately, and the technology behind converter valve control subsystem 220 is relatively mature. Therefore, energy storage valve control subsystem 230 can be expanded and developed based on converter valve control subsystem 220, facilitating engineering implementation.

[0084] It should be noted that the first power module and the second power module may be the same or different, which is not limited in the embodiment of the present application.

[0085] Optionally, in this embodiment of the present application, the energy storage valve control unit 231 is further configured to generate P third control instructions for the M battery modules based on instructions from the coordinated control subsystem 210. P is a positive integer less than or equal to M, and the M battery control units 233 are configured to respectively control the charge and discharge of the M battery modules based on the P third control instructions.

[0086] In one example, P is equal to M, that is, each battery module corresponds to a control instruction, and each battery control unit 233 corresponds to a control instruction. Each battery control unit 233 in the M battery control units 233 is responsible for receiving the corresponding control instruction generated by the energy storage valve control unit 231 and controlling the operation of the corresponding battery module, for example, controlling the corresponding battery module to charge and discharge. In another example, P is less than M, that is, only some of the M battery control units 233 receive the control instruction. These battery control units 233 can control the operation of the corresponding battery module according to the received control instruction, for example, controlling the corresponding battery module to charge and discharge, while the other battery control units 233 that do not receive the control instruction can control the corresponding battery module to be in a default state, for example, defaulting to not charging or defaulting to not discharging.

[0087] In this embodiment, the M battery control units 233 can communicate directly with the energy storage valve control unit 231, which is conducive to the second power control unit 232 and the battery control unit 233 controlling the second power module and the battery module in parallel, thereby improving the control efficiency of the system.

[0088] Optionally, in an embodiment of the present application, each battery control unit 233 of the M battery control units 233 is further configured to upload status information of the corresponding battery module to the energy storage valve control unit 231 .

[0089] Optionally, the status information of the battery module may include at least one battery parameter such as the voltage, power, temperature, state of charge (SOC), temperature, and current of the battery module. Optionally, the status information of the battery module may also be a function of the various battery parameters mentioned above. The battery control unit 233 may upload the status information of the corresponding battery module according to the requirements of the energy storage valve control unit 231. In other words, the battery control unit 233 only uploads the required status information based on the status information required by the energy storage valve control unit 231.

[0090] In this embodiment, the battery control unit 233 uploads the status information of the corresponding battery module to the energy storage valve control unit 231, so that the energy storage valve control unit 231 can timely understand the status of the battery module and perform corresponding control on the battery module, thereby ensuring the control reliability of the energy storage valve control subsystem 230.

[0091] Optionally, in an embodiment of the present application, the M second power control units 232 are also used to generate R fourth control instructions for the M battery modules according to the M second control instructions, where R is a positive integer less than or equal to M; the M battery control units 233 are used to control the charging and discharging of the M battery modules according to the R fourth control instructions.

[0092] That is, the M battery control units 233 do not communicate directly with the energy storage valve control unit 231 , but communicate indirectly with the energy storage valve control unit 231 through the M second power control units 232 .

[0093] In one example, R is equal to M, that is, each battery module corresponds to a control instruction, and each battery control unit 233 corresponds to a control instruction. Each battery control unit 233 in the M battery control units 233 is responsible for receiving the corresponding control instruction generated by the corresponding second power control unit 232 and controlling the operation of the corresponding battery module, for example, controlling the corresponding battery module to charge and discharge. In another example, R is less than M, that is, only some of the M battery control units 233 receive the control instruction sent by the corresponding second power control unit 232. These battery control units 233 can control the operation of the corresponding battery module according to the received control instruction, for example, control the corresponding battery module to charge and discharge, while the other battery control units 233 that have not received the control instruction can control the corresponding battery module to be in a default state, for example, defaulting to not charging or defaulting to not discharging.

[0094] In this embodiment, the M battery control units 233 are respectively controlled by the M second power control units 232 , which can reduce the communication load of the energy storage valve control unit 231 .

[0095] Optionally, in the embodiment of the present application, each battery control unit 233 of the M battery control units 233 is further configured to upload status information of the corresponding battery module to the corresponding second power control unit 232 .

[0096] Similar to the above embodiment, the status information of the battery module may include at least one battery parameter such as the voltage, power, temperature, state of charge (SOC), temperature, and current of the battery module. Optionally, the status information of the battery module may also be a function of the various battery parameters mentioned above. The battery control unit 233 may upload the status information of the battery module to the second power control unit 232 based on the content of the fourth control instruction. That is, the battery control unit 233 uploads the information indicated by the fourth control instruction.

[0097] In this embodiment, the battery control unit 233 uploads the status information of the corresponding battery module to the second power control unit 232, so that the second power control unit 232 can promptly feedback the status of the battery module to the energy storage valve control unit 231 and perform corresponding control on the battery module, thereby ensuring the control reliability of the energy storage valve control subsystem 230.

[0098] Optionally, in the embodiment of the present application, each second power control unit 232 of the M second power control units 232 is further configured to upload status information of the corresponding second power module to the energy storage valve control unit 231 .

[0099] Optionally, the status information of the second power module mainly includes states such as on, off, locked, and fault. In other words, the status information of the second power module is used to indicate to the energy storage valve control unit 231 whether the corresponding second power module is currently in the state of on, off, locked, or fault. Furthermore, if the second power module is in the fault state, the status information of the second power module is also used to indicate to the energy storage valve control unit 231 the current fault of the corresponding second power module.

[0100] In this embodiment, the second power control unit 232 uploads the status information of the second power modules to the energy storage valve control unit 231, which helps the energy storage valve control unit 231 to timely understand the status of each second power module, thereby ensuring the reliability of system control.

[0101] Optionally, in an embodiment of the present application, the energy storage valve control unit 231 is further configured to upload valve control status information of the energy storage valve to the coordination control subsystem 210 .

[0102] Optionally, the valve control state information of the energy storage valve primarily includes three states: locked, faulty, or operational. In other words, the valve control state information is used to indicate to the coordinated control subsystem 210 whether the energy storage valve is currently locked, faulty, or operational. Furthermore, if the energy storage valve is in a faulty state, the valve control state information of the energy storage valve is also used to indicate to the coordinated control subsystem 210 the current fault of the energy storage valve.

[0103] Optionally, the energy storage valve control unit 231 can also determine the valve control status information of the energy storage valve based on the status information of the M second power modules reported by the M second power control units 232 and the status information of the M battery modules reported by the M battery control units 233, and then report the determined valve control status information to the coordination control subsystem 210.

[0104] In this embodiment, the valve control status information of the energy storage valve is uploaded to the coordination control subsystem 210 through the energy storage valve control unit 231, which helps the coordination control subsystem 210 to timely understand the status of the energy storage valve, so as to better coordinate and control the operation of the energy storage valve and the energy storage valve, thereby ensuring the reliability of system control.

[0105] Optionally, in the embodiment of the present application, the second power control unit 232 and the battery control unit 233 corresponding to the same energy storage module communicate with each other.

[0106] Optionally, in an embodiment of the present application, the energy storage valve control subsystem 230 further includes: a battery monitoring unit, configured to obtain battery data of the M battery modules.

[0107] Optionally, the battery data may include all battery parameters of the battery module, including voltage, power, temperature, state of charge (SOC), temperature, current, etc. The battery data is actively reported to the battery monitoring unit by the battery control unit 233 .

[0108] In an example, each battery control unit 233 may communicate with a battery monitoring unit, that is, each battery control unit 233 directly reports the battery data of the corresponding battery module to the battery monitoring unit.

[0109] In other examples, each battery control unit 233 uses daisy chain communication, and only the first and last battery control units 233 in the daisy chain communicate directly with the battery monitoring unit. That is, the first and last battery control units 233 in the daisy chain can aggregate the battery data acquired by all battery control units 233 and upload the aggregated battery data to the battery monitoring unit.

[0110] Optionally, no matter which of the above examples the battery monitoring unit adopts to obtain the battery data of the M battery modules, daisy chain communication can be adopted between the M battery control units 233 .

[0111] Optionally, in this embodiment, the energy storage valve control subsystem 230 includes multiple energy storage valve control units 231, each of the multiple energy storage valve control units 231 communicates with M second power control units 232, and the multiple energy storage valve control units 232 communicate with each other.

[0112] Optionally, the multiple energy storage valve control units 231 can communicate with each other, exchange control information, and switch between master and slave modes. That is, one of the multiple energy storage valve control units 231 is the master control unit, while the remaining energy storage valve control units 231 are slave control units. If the master control unit fails, one of the slave control units can be set as the master control unit.

[0113] It should be understood that the multiple energy storage valve control units 231 can be integrated into different plug-ins within the same device, or can be provided in different devices; similarly, the M second power control units 232 can be integrated into different plug-ins within the same device, or can be provided in different devices; and the M battery control units 233 can be integrated into different plug-ins within the same device, or can be provided in different devices. Furthermore, the energy storage valve control unit 231, the second power control unit 232, and the battery control unit 233 can be integrated into different plug-ins within the same device, or can be provided in different devices, and this is not limited in the present embodiment.

[0114] In this embodiment, the energy storage valve control subsystem 230 includes multiple energy storage valve control units 231, and the multiple energy storage valve control units 231 communicate with each other and communicate with M second power control units 232, which can meet the redundant design requirements of the energy storage valve control subsystem 230 and ensure the control reliability of the energy storage valve control subsystem 230.

[0115] Optionally, in an embodiment of the present application, the coordinated control subsystem 210 includes multiple system control units, each of which communicates with the converter valve control subsystem 220 and the energy storage valve control subsystem 230, and the multiple system control units communicate with each other.

[0116] Optionally, the multiple system control units can communicate with each other, exchange control information, and switch between master and slave modes. That is, one of the multiple system control units can be the master control unit, while the remaining system control units can be slave control units. If the master control unit fails, one of the slave control units can be set as the master control unit.

[0117] It should be understood that the multiple system control units can be integrated into different plug-ins in the same device, or can be set in different devices, and the embodiments of the present application are not limited to this.

[0118] In this embodiment, the coordinated control subsystem 210 includes multiple system control units, and the multiple system control units communicate with each other and communicate with the converter valve control subsystem 220 and the energy storage valve control subsystem 230, which can meet the redundant design requirements of the coordinated control subsystem 210 and ensure the control reliability of the coordinated control subsystem 210.

[0119] Optionally, in an embodiment of the present application, the converter valve control subsystem 220 is integrated into the converter valve, and the energy storage valve control subsystem 230 is integrated into the energy storage valve.

[0120] The control system of the energy storage system provided in the embodiment of the present application will be described in detail below with reference to FIG8 and FIG9 .

[0121] Figure 8 is a diagram of the three-layer control architecture of the energy storage valve control subsystem. As shown in Figure 8, the control system includes a coordinated control subsystem, a converter valve control subsystem, and an energy storage valve control subsystem. The coordinated control subsystem includes a system control unit A and a system control unit B, which communicate with each other and exchange control information. The converter valve control subsystem includes two converter valve control units (converter valve control unit A and converter valve control unit B, which communicate with each other and exchange control information) and N first power control units (first power control unit 1, first power control unit 2, ..., first power control unit N-1, first power control unit N). The energy storage valve control subsystem includes N energy storage valve control units (energy storage valve control unit A and energy storage valve control unit B, which communicate with each other and exchange control information), M second power control units (second power control unit 1, second power control unit 2, ..., second power control unit M), M battery control units (battery control unit 1, battery control unit 2, ..., battery control unit M), and a battery monitoring unit. The system control unit A generates control instructions and sends them to the converter valve control unit A and the energy storage valve control unit A. The system control unit B generates control instructions and sends them to the converter valve control unit B and the energy storage valve control unit B. The converter valve control units A and B send switching instructions to the first power control units 1-N based on the control instructions generated by the system control units A and B, respectively. The first power control units 1-N send the status of the controlled first power modules to the converter valve control units A and B, respectively. The converter valve control unit A sends the valve control status of the converter valve to the system control unit A, and the converter valve control unit B sends the valve control status of the converter valve to the system control unit B. The energy storage valve control units A and B send switching instructions to the second power control units 1-M based on the control instructions generated by the system control units A and B, respectively. The second power control units 1-M send the status of the second power modules to the energy storage valve control units A and B, respectively. The second power control unit 1-M can also send charge and discharge instructions to the battery control unit 1-M respectively. On the one hand, the battery control unit 1-M controls the charging and discharging of the battery module according to the charge and discharge instructions, and uploads the battery status of the battery module to the second power control unit 1-M. On the other hand, the battery control units 1-M are connected by daisy chain communication to collect the battery data obtained by the battery control unit 1-M into the battery monitoring unit.

[0122] Figure 9 is a diagram of the two-layer control architecture of the energy storage valve control subsystem. As shown in Figure 9, the control system includes a coordinated control subsystem, a converter valve control subsystem, and an energy storage valve control subsystem. The coordinated control subsystem includes a system control unit A and a system control unit B, which communicate with each other and exchange control information. The converter valve control subsystem includes two converter valve control units (converter valve control unit A and converter valve control unit B, which communicate with each other and exchange control information) and N first power control units (first power control unit 1, first power control unit 2, ..., first power control unit N-1, first power control unit N). The energy storage valve control subsystem includes N energy storage valve control units (energy storage valve control unit A and energy storage valve control unit B, which communicate with each other and exchange control information), M second power control units (second power control unit 1, second power control unit 2, ..., second power control unit M), M battery control units (battery control unit 1, battery control unit 2, ..., battery control unit M), and a battery monitoring unit. The system control unit A generates control instructions and sends them to the converter valve control unit A and the energy storage valve control unit A. The system control unit B generates control instructions and sends them to the converter valve control unit B and the energy storage valve control unit B. The converter valve control unit A and the converter valve control unit B send switching instructions to the first power control units 1-N based on the control instructions generated by the system control units A and B, respectively. The first power control units 1-N send status information of the controlled first power modules to the converter valve control units A and B. The energy storage valve control units A and B send switching instructions to the second power control unit 1-M and charge and discharge instructions to the battery control unit 1-M based on the control instructions generated by the system control units A and B, respectively. The second power control unit 1-M sends the status information of the second power module to the energy storage valve control unit A and the energy storage valve control unit B. The battery control unit 1-M controls the charging and discharging of the battery module according to the charge and discharge instructions and uploads the battery status of the battery module to the energy storage valve control unit A and the energy storage valve control unit B. Furthermore, the battery control units 1-M are connected to each other via daisy chain communication, and the battery data obtained by the battery control units 1-M are aggregated to the battery monitoring unit. In addition, the second power control unit and the battery control unit corresponding to the same energy storage module communicate with each other and exchange control information.

[0123] FIG10 shows a schematic block diagram of a control method 300 for an energy storage system according to an embodiment of the present application. The energy storage system includes a converter valve and an energy storage valve, wherein the energy storage valve is connected to the DC side of the converter valve. Optionally, the control method may be executed by the coordinated control subsystem described above. As shown in FIG10 , the control method 300 includes:

[0124] S310, sending a first instruction to the converter valve control subsystem and a second instruction to the energy storage valve control subsystem, wherein the first instruction is used to control the operation of the converter valve, and the second instruction is used to control the operation of the energy storage valve.

[0125] It should be noted that the contents of control method 300 can be found in the various steps performed by the aforementioned coordinated control subsystem 210. Optionally, control method 200 may also include the various steps performed by the aforementioned converter valve subsystem 220 and energy storage valve subsystem 230, which are not further described here for the sake of brevity.

[0126] FIG11 is a schematic flow chart of a control method for an energy storage system based on the control architecture shown in FIG8 . Specifically, the control method includes: (1) the system control unit in the coordinated control subsystem determines the valve control instructions of the converter valve and the energy storage valve under different control modes through control mode selection, power calculation, power control (AC power / DC power) and internal and external dual-loop control (active power / reactive power); (2) in the converter valve control subsystem, the converter valve control unit completes the bridge arm current control, capacitor voltage balancing control and modulation, and generates the switching instruction of the first power module in the converter valve; (3) the first power control unit in the converter valve control subsystem completes the switching control of the first power control unit; (4) in the energy storage valve control subsystem, the energy storage valve control unit completes the battery current control, battery state balancing control and modulation, and generates the switching instruction of the first power module in the energy storage valve; (5) the second power control unit in the energy storage valve control subsystem completes the switching control of the second power module; (6) finally, the battery control unit in the energy storage valve control subsystem controls the battery module in the energy storage valve to charge and discharge according to the charge and discharge instructions generated by the second power control unit, and completes the battery information aggregation and calculation of the battery module.

[0127] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0128] An embodiment of the present application also provides a computer-readable storage medium for storing a computer program.

[0129] Optionally, the computer-readable storage medium can be applied to the control system in the embodiments of the present application, and the computer program enables the computer to execute the corresponding processes implemented by the control system in the various methods of the embodiments of the present application. For the sake of brevity, they will not be repeated here.

[0130] An embodiment of the present application also provides a computer program product, including computer program instructions.

[0131] Optionally, the computer program product can be applied to the control system in the embodiments of the present application, and the computer program instructions enable the computer to execute the corresponding processes implemented by the control system in the various methods of the embodiments of the present application. For the sake of brevity, they will not be repeated here.

[0132] The embodiment of the present application also provides a computer program.

[0133] Optionally, the computer program can be applied to the control system in the embodiments of the present application. When the computer program runs on a computer, the computer executes the corresponding processes implemented by the control system in the various methods of the embodiments of the present application. For the sake of brevity, they will not be repeated here.

[0134] Optionally, an embodiment of the present application further provides an energy storage system, which includes a converter valve and an energy storage valve, wherein the energy storage valve is connected to the DC side of the converter valve, and the high-voltage direct-mounted energy storage system may further include the control system described in the various embodiments above.

[0135] Optionally, in an embodiment of the present application, the converter valve is a VSC converter valve.

[0136] Furthermore, in an embodiment of the present application, the VSC converter valve adopts a modular multilevel converter (MMC) structure.

[0137] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A control system for an energy storage system, characterized in that: The energy storage system includes a converter valve and an energy storage valve, wherein the energy storage valve is connected to the DC side of the converter valve. The control system includes: a coordination control subsystem, a converter valve control subsystem and an energy storage valve control subsystem; The coordination control subsystem is used to send instructions to control the operation of the converter valve control subsystem and the energy storage valve control subsystem; The converter valve control subsystem is used to control the operation of the converter valve according to the instructions of the coordination control subsystem; The energy storage valve control subsystem is used to control the operation of the energy storage valve according to the instructions of the coordination control subsystem.

2. The control system according to claim 1, characterized in that: The converter valve includes N first power modules, and the converter valve control subsystem includes a converter valve control unit and N first power control units, where N is a positive integer; The converter valve control unit is configured to generate K first control instructions for the N first power modules according to an instruction of the coordinated control subsystem, where K is a positive integer less than or equal to N; The N first power control units are used to control the switching on or off of the N first power modules respectively according to the K first control instructions.

3. The control system according to claim 2, characterized in that: Each of the N first power control units is further configured to upload status information of the corresponding first power module to the converter valve control unit.

4. The control system according to claim 2 or 3, characterized in that: The converter valve control unit is further configured to upload valve control status information of the converter valve to the coordinated control subsystem.

5. The control system according to any one of claims 1 to 4, characterized in that: The energy storage valve includes M energy storage modules, each of the M energy storage modules includes a second power module and a battery module, and the energy storage valve control subsystem includes an energy storage valve control unit, M second power control units, and M battery control units, where M is a positive integer; The energy storage valve control unit is used to generate Q second control instructions for the M second power modules in the M energy storage modules according to the instructions of the coordinated control subsystem, where Q is a positive integer less than or equal to M; The M second power control units are used to control the switching on or off of the M second power modules according to the Q second control instructions; The M battery control units are used to respectively control the charging and discharging of the M battery modules in the M energy storage modules.

6. The control system according to claim 5, characterized in that: The energy storage valve control unit is also used to generate P third control instructions for the M battery modules according to the instructions of the coordinated control subsystem, where P is a positive integer less than or equal to M; the M battery control units are used to control the charging and discharging of the M battery modules respectively according to the P third control instructions.

7. The control system according to claim 6, characterized in that: Each of the M battery control units is further configured to upload status information of the corresponding battery module to the energy storage valve control unit.

8. The control system according to claim 5, characterized in that: The M second power control units are also used to generate R fourth control instructions for the M battery modules according to the Q second control instructions, where R is a positive integer less than or equal to M; the M battery control units are used to control the charging and discharging of the M battery modules according to the R fourth control instructions.

9. The control system according to claim 8, characterized in that: Each of the M battery control units is further configured to upload status information of the corresponding battery module to the corresponding second power control unit.

10. The control system according to any one of claims 5 to 9, characterized in that: The energy storage valve control unit is further configured to upload valve control status information of the energy storage valve to the coordinated control subsystem.

11. The control system according to any one of claims 5 to 10, characterized in that: Each of the M second power control units is further configured to upload status information of the corresponding second power module to the energy storage valve control unit.

12. The control system according to any one of claims 5 to 11, characterized in that: The second power control unit and the battery control unit corresponding to the same energy storage module communicate with each other.

13. The control system according to any one of claims 5 to 12, characterized in that: The energy storage valve control subsystem further includes: A battery monitoring unit is used to obtain battery data of the M battery modules.

14. The control system according to any one of claims 5 to 13, characterized in that: M is a positive integer greater than 1, and the M battery control units are connected to each other using a daisy chain communication method.

15. The control system according to any one of claims 2 to 4, characterized in that: The converter valve control subsystem includes a plurality of converter valve control units, each of the plurality of converter valve control units communicates with the N first power control units, and the plurality of converter valve control units communicate with each other.

16. The control system according to any one of claims 5 to 14, characterized in that: The energy storage valve control subsystem includes a plurality of energy storage valve control units, each of the plurality of energy storage valve control units communicates with the M second power control units, and the plurality of energy storage valve control units communicate with each other.

17. The control system according to any one of claims 1 to 16, characterized in that: The coordinated control subsystem includes a plurality of system control units, each of which communicates with the converter valve control subsystem and the energy storage valve control subsystem, and the plurality of system control units communicate with each other.

18. The control system according to any one of claims 1 to 17, characterized in that: The converter valve control subsystem is integrated into the converter valve, and the energy storage valve control subsystem is integrated into the energy storage valve.

19. An energy storage system, characterized in that: The energy storage system comprises a converter valve and an energy storage valve, wherein the energy storage valve is connected to the DC side of the converter valve. The energy storage system further comprises a control system according to any one of claims 1 to 18.

20. A control method for an energy storage system, characterized in that: The energy storage system includes a converter valve and an energy storage valve, wherein the energy storage valve is connected to the DC side of the converter valve. The control method includes: A first instruction is sent to the converter valve control subsystem and a second instruction is sent to the energy storage valve control subsystem, wherein the first instruction is used to control the operation of the converter valve and the second instruction is used to control the operation of the energy storage valve.

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