Method and device for controlling high-voltage energy storage system to enter maintenance state

Abstract

The invention relates to a method and device for controlling a high-voltage energy storage system to enter a maintenance state, computer equipment and a storage medium, and relates to the technical field of high-voltage energy storage, the high-voltage energy storage system comprises at least one energy storage branch, and the energy storage branch comprises a plurality of cascaded energy storage sub-modules; the method in one embodiment comprises the following steps: controlling an energy storage branch to be overhauled to be in a no-power output state; the branch voltage of the energy storage branch to be overhauled is controlled to be smaller than a branch voltage safety value; controlling the current of a to-be-overhauled energy storage sub-module in the to-be-overhauled energy storage branch to be smaller than a current safety value; and grounding the shell of the to-be-overhauled energy storage sub-module. By adopting the scheme of the embodiment, the safety problem caused by the fact that the to-be-overhauled energy storage branch and the to-be-overhauled energy storage sub-module in the energy storage branch are in the high-voltage state is reduced, so that the energy storage branch can enter the state that a maintainer can perform on-machine maintenance, and the maintenance safety is improved.

Description

Technical Field

[0001] The present application relates to the field of high-voltage energy storage technology, and in particular to a method, apparatus, computer equipment, storage medium, and computer program product for controlling a high-voltage energy storage system to enter a maintenance state. Background Art

[0002] Currently, high-voltage energy storage systems, as a new type of energy storage system, are in their infancy in terms of research and implementation, with few actual projects available. Consequently, the development of maintenance methods for these systems is also lacking. High-voltage energy storage systems utilize a cascaded structure of energy storage submodules. The voltages to ground vary across various devices in the system, with the submodule with the highest voltage to ground reaching tens or even hundreds of kilovolts (AC or DC). In high-voltage energy storage systems, the voltages of the system submodules and battery pack casings are typically clamped in some way, ensuring that the casing voltage of each submodule is at a high voltage relative to ground. This prevents maintenance personnel from directly accessing the system for maintenance. Therefore, there is an urgent need to provide a means to make the high-voltage energy storage system accessible for maintenance, based on its characteristics. This would allow personnel to access the system for on-site maintenance, thereby resolving the design challenges of difficult inspections. Summary of the Invention

[0003] Based on this, it is necessary to provide a method, device, computer equipment, storage medium and computer program product for controlling a high-voltage energy storage system to enter a maintenance state, which can control a high-voltage energy storage battery to enter a maintenance state, in order to address the above technical problems.

[0004] In a first aspect, the present application provides a method for controlling a high-voltage energy storage system to enter a maintenance state, wherein the high-voltage energy storage system includes at least one energy storage branch, and the energy storage branch includes a plurality of cascaded energy storage submodules; wherein the method includes:

[0005] Control the energy storage branch to be repaired to be in a no-power output state;

[0006] Controlling the branch voltage of the energy storage branch to be repaired to be less than a branch voltage safety value;

[0007] The current of the energy storage submodule to be repaired in the energy storage branch to be repaired is controlled to be less than a current safety value; and the shell of the energy storage submodule to be repaired is grounded.

[0008] Based on the method for controlling a high-voltage energy storage system to enter a maintenance state in the embodiment of the present application as described above, when it is necessary to control the high-voltage energy storage system to enter a maintenance state, the energy storage branch to be repaired is controlled to be in a no-power output state, so that the energy storage branch to be repaired has no power output, and the branch voltage of the energy storage branch to be repaired is controlled to be less than the branch voltage safety value, so that the energy storage branch to be repaired is in a maintenance preparation state, and by controlling the current of the energy storage submodule to be repaired in the energy storage branch to be repaired to be less than the current safety value, the current caused by the battery in the energy storage submodule to be repaired can be within the current safety value to ensure maintenance safety, and the energy storage submodule to be repaired can be placed in a maintenance preparation state. The shell of the block is grounded, so that the shell voltage of the energy storage submodule to be repaired is reduced to the ground potential, so as to further ensure the safety of maintenance. After the above operation, the energy storage branch to be repaired can be put into a no-power output state, the branch voltage of the energy storage branch to be repaired is within the range of the branch voltage safety value, the current in the energy storage submodule to be repaired is within the range of the current safety value, and the shell voltage of the energy storage submodule to be repaired is reduced to the ground potential, which reduces the safety problems caused by the energy storage branch to be repaired and the energy storage submodule to be repaired in the energy storage branch being in a high-voltage state, so that it can enter a state where maintenance personnel can perform on-board maintenance, thereby improving the safety of maintenance.

[0009] In one embodiment, controlling the energy storage branch to be repaired to be in a no-power output state includes:

[0010] The branch current of the energy storage branch to be repaired is controlled to be 0.

[0011] Based on the solution of this embodiment, by controlling the branch current of the energy storage branch to be repaired to 0, the branch current of the energy storage branch to be repaired can be made 0, that is, there is no current output as a whole, and thus it is in a no-power output state, which can make the energy storage branch to be repaired in a maintenance preparation state to improve safety.

[0012] In some embodiments, controlling the energy storage branch to be repaired to be in a no-power output state includes:

[0013] The energy storage branch to be repaired is controlled to be in a locked state so that the branch current of the energy storage branch to be repaired is less than a preset value.

[0014] Based on the solution of this embodiment, by controlling the energy storage branch to be repaired to be in a locked state, when the energy storage branch to be controlled is in a locked state, theoretically no branch current flows through the energy storage branch to be repaired, that is, there is no current output as a whole, the branch current is less than a preset value, and it is in a no-power output state. The control method is simple and convenient, and the operability is strong.

[0015] In some embodiments, controlling the energy storage branch to be repaired to be in a locked state includes:

[0016] A locking instruction is sent to the branch controller of the energy storage branch to be repaired, wherein the locking instruction is used to control the energy storage branch to be repaired to stop switching, so that the energy storage branch to be repaired is in a locked state.

[0017] Therefore, when the energy storage branch to be repaired is controlled to be in a locked state, it can be achieved by sending a locking instruction to the branch controller of the energy storage branch to be repaired. The energy storage branch to be repaired can stop switching based on the locking instruction, so that the energy storage branch to be repaired is in a locked state. At this time, the branch current of the energy storage branch to be repaired is less than the preset value, that is, there is no current output as a whole, and it is in a no-power output state. The control method is simple and convenient, and the operability is strong.

[0018] In one embodiment, the sending of a locking instruction to the branch controller of the energy storage branch to be repaired, wherein the locking instruction is used to control the energy storage branch to be repaired to stop switching so that the energy storage branch to be repaired is in a locked state, includes:

[0019] A locking instruction is sent to the submodule controller of the energy storage submodule of the energy storage branch to be repaired, wherein the locking instruction is used to instruct the submodule controller to turn off the IGBT of the power module in the energy storage submodule, and the branch controller includes the submodule controller.

[0020] Therefore, when a locking instruction is sent to the branch controller of the energy storage branch to be repaired to control the energy storage branch to be repaired to stop switching, the submodule controller can be specifically instructed to turn off the IGBT of the power module in the energy storage submodule. That is, by turning off the IGBT of the power module in the energy storage submodule, the energy storage submodule of the energy storage branch to be repaired can be stopped from switching, so that the branch current of the energy storage branch to be repaired is 0. The control method is simple and convenient, and the operability is strong.

[0021] In some embodiments, after controlling the energy storage branch to be repaired to be in a no-power output state and before controlling the voltage of the energy storage branch to be repaired to be less than a branch voltage safety value, the method further includes:

[0022] The energy storage branch to be repaired is controlled to be in an isolated and open state.

[0023] Based on this embodiment, after controlling the energy storage branch to be repaired to be in a no-power output state, the energy storage branch to be repaired is further controlled to be in an isolated and disconnected state, thereby isolating and disconnecting the current of the energy storage branch to be repaired, thereby further improving the safety of the repair state.

[0024] In some embodiments, controlling the energy storage branch to be repaired to be in an isolated and tripped state includes:

[0025] The isolating switch of the energy storage branch to be repaired is controlled to be in an open state.

[0026] Since the isolating switch of the energy storage branch can provide a visible break in the air but cannot interrupt the current, when the energy storage branch to be repaired is controlled to be in an isolated and disconnected state, by controlling the isolating switch of the energy storage branch to be repaired to be in an open state, the possibility of current passing through the energy storage valve can be reduced, thereby further improving the safety of maintenance.

[0027] In some embodiments, after controlling the isolating switch of the energy storage branch to be repaired to be in an open state, the method further includes:

[0028] The isolating switch state of the isolating switch of the energy storage branch to be repaired is detected, and whether the isolating switch is correctly opened is determined according to the isolating switch state.

[0029] Therefore, after performing the work of opening the isolating switch of the energy storage branch to be repaired, the isolating switch status of the isolating switch of the energy storage branch to be repaired is further detected to ensure that the isolating switch of the energy storage branch to be repaired is correctly opened, so as to further improve the maintenance safety.

[0030] In some embodiments, after controlling the energy storage branch to be repaired to be in a no-power output state and before controlling the branch voltage of the energy storage branch to be repaired to be less than a branch voltage safety value, the process further includes:

[0031] The energy storage branch to be repaired is controlled to be in a disconnected state.

[0032] Thus, after controlling the energy storage branch to be repaired to be in a no-power output state, the energy storage branch to be repaired is further disconnected, so that the energy storage circuit to be repaired is in a disconnected state, reducing the possibility of current existing due to the energy storage circuit to be repaired not being disconnected, and further improving the repair safety.

[0033] In some embodiments, controlling the energy storage branch to be repaired to be in a disconnected state includes:

[0034] The circuit breaker of the energy storage branch to be repaired is controlled to be in an open state.

[0035] Therefore, when a circuit breaker is provided for the energy storage branch to be repaired, the current of the energy storage branch to be repaired can be disconnected by controlling the circuit breaker of the energy storage branch to be repaired to be in the open state, thereby further improving the safety of the repair state.

[0036] In some embodiments, after controlling the circuit breaker of the energy storage branch to be repaired to be in an open state, the method further includes:

[0037] Detect the circuit breaker status of the circuit breaker of the energy storage branch to be repaired, and determine whether the circuit breaker is correctly opened according to the circuit breaker status.

[0038] Therefore, after executing the work of controlling the circuit breaker of the energy storage branch to be repaired to be in the open state, the circuit breaker state of the circuit breaker of the energy storage branch to be repaired is further detected to ensure that the circuit breaker of the energy storage branch to be repaired is correctly opened, so as to further improve the maintenance safety.

[0039] In some embodiments, controlling the energy storage branch to be repaired to be in a disconnected state includes:

[0040] The fast switch of the energy storage branch to be repaired is controlled to be in an open state.

[0041] In a high-voltage energy storage system, a fast switch can quickly cut off the fault current when a fault occurs, and has a fast opening and closing speed. Therefore, when it is necessary to control the energy storage branch to be repaired in a disconnected state, by controlling the fast switch of the energy storage branch to be repaired in an open state, it can meet the need to disconnect the energy storage branch to be repaired, improve the safety of the maintenance state, and help improve maintenance efficiency.

[0042] In some embodiments, after controlling the fast switch of the energy storage branch to be repaired to be in an open state, the method further includes:

[0043] The fast switching state of the fast switch of the energy storage branch to be repaired is detected, and whether the fast switch is correctly opened is determined according to the fast switching state.

[0044] Therefore, after executing the work of controlling the fast switch of the energy storage branch to be repaired to be in the open state, the fast switching state of the fast switch of the energy storage branch to be repaired is further detected to ensure that the fast switch of the energy storage branch to be repaired is correctly opened, so as to further improve the safety of maintenance.

[0045] In some embodiments, controlling the voltage of the energy storage branch to be repaired to be less than a branch voltage safety value includes:

[0046] The voltage reduction module of the energy storage branch to be repaired is used to perform voltage reduction processing so that the voltage of the energy storage branch to be repaired is less than the branch voltage safety value.

[0047] Based on this embodiment, a step-down module can be configured for the energy storage branch. During the normal operation of the energy storage branch, the step-down module is not enabled. When it is necessary to enter the maintenance state for maintenance and it is necessary to control the voltage of the energy storage branch to be repaired to be lower than the branch voltage safety value, the step-down module is enabled to perform voltage reduction processing through the step-down module so that the voltage of the energy storage branch to be repaired is lower than the branch voltage safety value, thereby improving maintenance safety.

[0048] In some embodiments, controlling the voltage of the energy storage branch to be repaired to be less than a branch voltage safety value includes:

[0049] Control the energy storage branch to be repaired to be grounded.

[0050] Based on this embodiment, since most high-voltage energy storage systems are series systems, when not grounded, the system voltage and the shell voltage of each submodule are still in a suspended state. Therefore, when it is necessary to control the voltage of the energy storage branch to be repaired to be lower than the branch voltage safety value, by controlling the grounding switch of the energy storage branch to be repaired to be closed, one or both ends of the grounding switch of the energy storage branch to be repaired can be at the ground potential, which can further improve safety and the control method is simple and convenient.

[0051] In some embodiments, controlling the energy storage branch to be repaired to be grounded includes:

[0052] Control the grounding switch of the energy storage branch to be repaired to close.

[0053] Based on this embodiment, when it is necessary to control the grounding of the energy storage branch to be repaired, by controlling the closing of the grounding switch of the energy storage branch to be repaired, one or both ends of the grounding switch of the energy storage branch to be repaired can be at the ground potential, which can further improve safety. The control method is simple and convenient, and no additional devices are required.

[0054] In some embodiments, after controlling the energy storage branch to be repaired to be grounded, the method further includes:

[0055] The grounding switch state of the grounding switch of the energy storage branch to be repaired is detected, and whether the grounding switch is correctly closed is determined according to the grounding switch state.

[0056] Therefore, after executing the work of controlling the closing of the grounding switch of the energy storage branch to be repaired, the grounding state of the grounding switch of the energy storage branch to be repaired is further detected to ensure that the grounding switch of the energy storage branch to be repaired is correctly closed, thereby further improving the safety of repair.

[0057] In one embodiment, the energy storage submodule includes an energy storage battery and a power module, and controlling the current of the energy storage submodule to be repaired in the energy storage branch to be repaired to be less than a current safety value includes:

[0058] The capacitor in the power module of the energy storage submodule to be repaired is controlled to discharge, so that the current of the energy storage submodule to be repaired in the energy storage branch to be repaired is less than the current safety value.

[0059] Since in the high-voltage energy storage system, the energy storage submodule is large in size, and the capacitors in the power module of the energy storage submodule are in a high-voltage state, it is easy for current to flow in the energy storage submodule. Therefore, by controlling the discharge of the capacitors in the power module of the energy storage submodule to be repaired, the voltage of the capacitors in the power module can be reduced, so that the current of the energy storage submodule to be repaired in the energy storage branch to be repaired is less than the current safety value, allowing maintenance personnel to enter the energy storage submodule to be repaired for maintenance, so as to further ensure maintenance safety.

[0060] In some embodiments, the power module includes a capacitor and a resistor; and controlling the discharge of the capacitor in the power module of the energy storage submodule to be repaired includes:

[0061] The connection between the energy storage battery of the energy storage submodule to be repaired and the power module is disconnected, so that the capacitor in the power module discharges to the resistance of the power module.

[0062] In high-voltage energy storage systems, some energy storage submodules are provided with capacitors and resistors. Therefore, by disconnecting the connection between the energy storage battery of the energy storage submodule to be repaired and the power module, the capacitor and the resistor in the power module form a loop. Based on this loop, the capacitor of the power module will discharge the resistor of the power module, thereby reducing the voltage of the capacitor in the power module, making the current of the energy storage submodule to be repaired in the energy storage branch to be repaired less than the current safety value, allowing maintenance personnel to enter the energy storage submodule to be repaired for maintenance, so as to further ensure maintenance safety.

[0063] In some embodiments, disconnecting the energy storage battery and the power module of the energy storage submodule to be repaired includes:

[0064] Disconnect the isolation switch between the parallel energy storage battery and the power module of the energy storage submodule to be repaired.

[0065] Since there are usually multiple energy storage batteries in the energy storage submodule, and these multiple energy storage batteries are connected to the power module in parallel, when it is necessary to disconnect the energy storage batteries of the energy storage submodule to be repaired and the power module, the parallel energy storage batteries of the energy storage submodule to be repaired and the power module can be directly disconnected by disconnecting the isolation switch between the parallel energy storage batteries of the energy storage submodule to be repaired and the power module. This can put the parallel energy storage batteries of the energy storage submodule to be repaired and the power module into a disconnected state, so that the power module is disconnected from the parallel energy storage batteries, and the capacitor and the resistor in the power module form a loop. Based on this loop, the capacitor of the power module will discharge the resistor of the power module, so that the voltage of the capacitor in the power module is reduced, so that the current of the energy storage submodule to be repaired in the energy storage branch to be repaired is less than the current safety value. In addition, by disconnecting the isolation switch, a visible breakpoint can be provided, which can improve reliability.

[0066] In some embodiments, disconnecting the energy storage battery and the power module of the energy storage submodule to be repaired includes:

[0067] Disconnect the branch switch of the parallel energy storage battery.

[0068] Since there are usually multiple energy storage batteries in the energy storage submodule, and these multiple energy storage batteries are connected to the power module in parallel, when it is necessary to disconnect the connection between the energy storage battery of the energy storage submodule to be repaired and the power module, the branch switch of the parallel energy storage battery can be directly disconnected to put the energy storage switch of the parallel energy storage battery into an off state, so that there is no current on the busbar of the energy storage battery, and the capacitor and the resistor in the power module form a loop. Based on this loop, the capacitor of the power module will discharge the resistor of the power module, so that the voltage of the capacitor in the power module is reduced, so that the current of the energy storage submodule to be repaired in the energy storage branch to be repaired is less than the current safety value.

[0069] In some embodiments, disconnecting the energy storage battery and the power module of the energy storage submodule to be repaired includes:

[0070] Disconnect the isolation switch between the parallel energy storage battery and the power module and the branch switch of the parallel energy storage battery.

[0071] Since there are usually multiple energy storage batteries in the energy storage submodule, and these multiple energy storage batteries are connected to the power module in parallel, when it is necessary to disconnect the energy storage battery of the energy storage submodule to be repaired and the power module, both the isolating switch between the parallel energy storage batteries of the energy storage submodule to be repaired and the power module is disconnected, and the branch switch of the parallel energy storage batteries is disconnected. Disconnecting the isolating switch not only provides a visible breakpoint, thereby improving reliability, but also eliminates current on the busbar of the energy storage battery. Through the dual control method, the capacitor and the resistor in the power module form a loop, so that based on this loop, the capacitor of the power module discharges the resistor of the power module, thereby improving the reliability of disconnecting the energy storage battery of the energy storage submodule to be repaired and the power module, and increasing the possibility of ensuring that the current of the energy storage submodule to be repaired in the energy storage branch to be repaired is less than the current safety value.

[0072] In some embodiments, the energy storage submodule further includes a discharge module, and the power module is connected to either the energy storage battery or the discharge module;

[0073] The controlling the discharge of the capacitor in the power module of the energy storage submodule to be repaired includes:

[0074] The power module is controlled to switch to be connected to the discharge module, so that the capacitor in the power module is discharged through the discharge module.

[0075] Therefore, a special discharge module is set in the energy storage submodule, and the power module is connected to the energy storage battery and the discharge module in a selective manner. During the normal operation of the energy storage submodule, the power module is connected to the energy storage module. When it is necessary to enter the maintenance state for maintenance, the power module is disconnected from the energy storage module and switched to the discharge module. The capacitor of the power module will be discharged through the discharge module, thereby reducing the voltage of the capacitor in the power module, making the current of the energy storage submodule to be repaired in the energy storage branch to be repaired less than the current safety value, so that maintenance personnel can enter the energy storage submodule to be repaired for maintenance, so as to further improve maintenance safety.

[0076] In one embodiment, after disconnecting the isolation switch between the parallel energy storage battery and the power module, the method further includes:

[0077] The isolating switch state of the isolating switch of the energy storage submodule to be repaired is detected, and whether the isolating switch is correctly opened is determined according to the isolating switch state.

[0078] Therefore, after disconnecting the isolating switch between the parallel energy storage battery and the power module, the switching state of the isolating switch of the energy storage submodule to be repaired is further detected to ensure that the isolating switch of the energy storage submodule to be repaired is correctly opened, thereby further improving the maintenance safety.

[0079] In one embodiment, grounding the housing of the energy storage submodule to be repaired includes any one of the following:

[0080] Hanging the shell of the energy storage submodule to be repaired on a grounding rod;

[0081] Connecting the housing of the energy storage submodule to be repaired to the ground wire;

[0082] Close the standby grounding switch of the energy storage submodule to be repaired.

[0083] Therefore, when it is necessary to ground the shell of the energy storage submodule to be repaired, the shell of the energy storage submodule to be repaired can be grounded by hanging the shell of the energy storage submodule to be repaired on a grounding rod, connecting the shell of the energy storage submodule to be repaired to a ground wire, closing the standby grounding switch of the energy storage submodule to be repaired, etc., so that when actually performing the shell grounding operation, it can be selected according to the needs of the scene, which has strong flexibility and operability.

[0084] In a second aspect, the present application further provides a device for controlling a high-voltage energy storage system to enter a maintenance state, wherein the high-voltage energy storage system includes at least one energy storage branch, and the energy storage branch includes a plurality of cascaded energy storage submodules; wherein the device includes a branch control module and a submodule control module:

[0085] The branch control module is used to control the energy storage branch to be repaired to be in a no-power output state, and to control the voltage of the energy storage branch to be repaired to be less than a branch voltage safety value;

[0086] The submodule control module is used to control the current safety value of the energy storage submodule to be repaired in the energy storage branch to be repaired, and to ground the shell of the energy storage submodule to be repaired.

[0087] In a third aspect, the present application further provides a computer device comprising a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the method of any of the above embodiments when executing the computer program.

[0088] In a fourth aspect, the present application further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method of any of the above embodiments.

[0089] In a fifth aspect, the present application further provides a computer program product, which includes a computer program that, when executed by a processor, implements the steps of the method of any of the above embodiments.

[0090] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0091] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present application. The same reference numerals are used throughout the drawings to represent the same components. In the drawings:

[0092] Figure 1 A schematic diagram of the architecture of a high-voltage energy storage system in one embodiment;

[0093] Figure 2 A schematic diagram of the architecture of a high-voltage energy storage system in another embodiment;

[0094] Figure 3 A schematic diagram of the architecture of a high-voltage energy storage system in another embodiment;

[0095] Figure 4 1 is a flow chart of a method for controlling a high-voltage energy storage system to enter a maintenance state in one embodiment;

[0096] Figure 5 Schematic diagram of the structure of the energy storage submodule in one embodiment;

[0097] Figure 6 A flowchart of a method for controlling a high-voltage energy storage system to enter a maintenance state in another embodiment;

[0098] Figure 7 A flowchart of a method for controlling a high-voltage energy storage system to enter a maintenance state in another embodiment;

[0099] Figure 8 A flowchart of a method for controlling a high-voltage energy storage system to enter a maintenance state in another embodiment;

[0100] Figure 9 1 is a flow chart of a method for controlling a high-voltage energy storage system to enter a maintenance state in a specific example;

[0101] Figure 10 1 is a structural block diagram of a device for controlling a high-voltage energy storage system to enter a maintenance state in one embodiment;

[0102] Figure 11 FIG. 1 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0103] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0104] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0105] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments 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 figure descriptions are intended to cover non-exclusive inclusions.

[0106] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0107] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present 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 herein may be combined with other embodiments.

[0108] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0109] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0110] In the description of the embodiments of this application, unless otherwise specified or limited, technical terms such as "connection" should be understood in a broad sense. For example, it can refer to a mechanical connection or an electrical connection; it can refer to a direct connection or an indirect connection through an intermediate medium; it can refer to internal communication between two components or an interaction between two components. For those skilled in the art, the specific meanings of the above terms in the embodiments of this application can be understood based on the specific circumstances.

[0111] Currently, high-voltage energy storage systems, as a new type of energy storage system, are in their infancy in terms of research and implementation, with few actual projects available. Consequently, the development of maintenance methods for these systems is also lacking. Maintenance methods used in areas such as flexible direct current (FDC) are not applicable to high-voltage energy storage systems. This is because high-voltage energy storage systems utilize a cascaded structure of energy storage submodules, with the ground voltages of various devices in the system varying. The submodule with the highest ground voltage can reach tens or even hundreds of kilovolts (AC or DC). In high-voltage energy storage systems, the voltages of the system submodules and battery pack casings are typically clamped, ensuring that each submodule's casing voltage is at a high voltage relative to the ground. Therefore, maintenance personnel cannot directly access the system for maintenance.

[0112] Based on this, it is necessary to provide a means to make the high-voltage energy storage system maintainable according to the characteristics of the high-voltage energy storage system, so that it can be put into a state where personnel can conduct on-board maintenance.

[0113] Accordingly, the embodiment of the present application provides a method for controlling a high-voltage energy storage system to enter a maintenance state, which can be applied to a high-voltage energy storage system. Among them, some structural examples of the high-voltage energy storage system can be as follows Figures 1 to 3As shown. Combined Figures 1 to 3 As shown, the high-voltage energy storage system includes at least one energy storage branch, such as Figure 1 The energy storage branch 100 shown in FIG. 1 includes multiple energy storage submodules connected in cascade. Figures 1 to 3 The energy storage submodules SM#1, SM#2, SM#3, SM#n-1 and SM#n are shown in FIG. Figures 1 to 3 In the figure, only the components related to the solution of this application are shown. In actual technical application scenarios, the high-voltage energy storage system may include other components.

[0114] Based on this, if Figure 4 As shown, the method for controlling a high-voltage energy storage system to enter a maintenance state according to an embodiment of the present application includes:

[0115] Step S402: Control the energy storage branch to be repaired to be in a no-power output state.

[0116] The energy storage branch to be repaired refers to the energy storage branch that needs to be repaired. Since a high-voltage energy storage system generally includes multiple energy storage branches, when repair is required, one energy storage branch of the high-voltage energy storage system may be the energy storage branch to be repaired, or two or more energy storage branches of the high-voltage energy storage system may be the energy storage branches to be repaired. In some cases, all energy storage branches of the high-voltage energy storage system may be the energy storage branches to be repaired.

[0117] The no-power output state refers to a state in which no power is output, that is, no power is output to the outside. The energy storage branch to be repaired is in a no-power output state, that is, the energy storage branch to be repaired does not output power to the outside.

[0118] By controlling the energy storage branch to be repaired to be in a no-power output state, the energy storage branch to be repaired can be prevented from outputting power to the outside, thereby reducing the safety impact on maintenance personnel caused by the energy storage branch in the power output state, and helping to improve maintenance safety.

[0119] Step S404: controlling the branch voltage of the energy storage branch to be repaired to be less than a branch voltage safety value.

[0120] The branch voltage safety value refers to the voltage value of the energy storage branch, assuming maintenance personnel can enter the environment of the energy storage branch. In other words, if the branch voltage of the energy storage branch is within the branch voltage safety value, personnel entering the energy storage branch environment will not pose a safety threat to maintenance personnel. Or, there may be some impact on the safety of maintenance personnel, but the impact is minimal and within the acceptable safety impact range.

[0121] Since the voltage of the energy storage branch is relatively high, voltage may still exist in the energy storage branch even when the energy storage branch is in a state of no power output. Therefore, by controlling the branch voltage of the energy storage branch to be repaired to be lower than the branch voltage safety value, the branch voltage of the energy storage branch to be repaired can be made within the branch voltage safety value range, thereby reducing the safety impact of the maintenance personnel due to the excessively high voltage of the energy storage branch, and helping to improve the maintenance safety.

[0122] Step S406: controlling the current of the energy storage submodule to be repaired in the energy storage branch to be repaired to be less than the current safety value; and grounding the shell of the energy storage submodule to be repaired.

[0123] An energy storage submodule to be repaired refers to an energy storage submodule that requires repair. Since a single energy storage branch of a high-voltage energy storage system includes multiple cascaded energy storage submodules, one of the energy storage submodules in the energy storage branch to be repaired may be the energy storage submodule to be repaired, or two or more of the energy storage submodules in the energy storage branch to be repaired may be the energy storage submodules to be repaired. In some cases, all of the energy storage submodules in the energy storage branch to be repaired may be the energy storage submodules to be repaired.

[0124] The current safety value refers to the current value of the energy storage submodule, assuming maintenance personnel can enter the energy storage submodule environment. In other words, if the current of the energy storage submodule is within this current safety value, personnel entering the energy storage branch environment will not pose a safety threat to maintenance personnel. Or, while there may be some impact on the maintenance personnel's safety, the impact is minimal and within the acceptable safety impact range.

[0125] Since in a high-voltage energy storage system, the energy storage submodule can provide current for power supply, even when the energy storage branch has no power output and the branch voltage is less than the branch voltage safety value, a high current may still exist in the energy storage submodule. Therefore, by controlling the current of the energy storage submodule to be repaired to be less than the current safety value, the safety impact of the excessive current of the energy storage submodule to be repaired on the maintenance personnel is reduced, which helps to improve the maintenance safety. Moreover, in a high-voltage energy storage system, the energy storage submodule is generally large in size, and maintenance personnel need to enter the interior of the energy storage submodule for maintenance. The shell of the energy storage submodule may have a high voltage to ground. Therefore, by grounding the shell of the energy storage submodule to be repaired, the shell voltage of the energy storage submodule to be repaired is reduced to the ground potential, which enables maintenance personnel to safely enter the interior of the energy storage submodule to be repaired for maintenance, thereby improving maintenance safety.

[0126] Based on the method for controlling a high-voltage energy storage system to enter a maintenance state in the embodiment of the present application as described above, when it is necessary to control the high-voltage energy storage system to enter a maintenance state, the energy storage branch to be repaired is controlled to be in a no-power output state, so that the energy storage branch to be repaired has no power output, and the branch voltage of the energy storage branch to be repaired is controlled to be less than the branch voltage safety value, so that the energy storage branch to be repaired is in a maintenance preparation state, and by controlling the current of the energy storage submodule to be repaired in the energy storage branch to be repaired to be less than the current safety value, the current caused by the battery in the energy storage submodule to be repaired can be within the current safety value to ensure maintenance safety, and the energy storage submodule to be repaired can be placed in a maintenance preparation state. The shell of the block is grounded, so that the shell voltage of the energy storage submodule to be repaired is reduced to the ground potential, so as to further ensure the safety of maintenance. After the above operation, the energy storage branch to be repaired can be put into a no-power output state, the branch voltage of the energy storage branch to be repaired is within the range of the branch voltage safety value, the current in the energy storage submodule to be repaired is within the range of the current safety value, and the shell voltage of the energy storage submodule to be repaired is reduced to the ground potential, which reduces the safety problems caused by the energy storage branch to be repaired and the energy storage submodule to be repaired in the energy storage branch being in a high-voltage state, so that it can enter a state where maintenance personnel can perform on-board maintenance, thereby improving the safety of maintenance.

[0127] Among them, in the scheme of the above embodiment, the execution order of each step is not limited. For example, it can be that the energy storage branch to be repaired is first controlled to be in a no-power output state, and the branch voltage of the energy storage branch to be repaired is less than the branch voltage safety value, and then the current of the energy storage sub-module to be repaired in the energy storage branch to be repaired is controlled to be less than the current safety value. It can also be that the current of the energy storage sub-module to be repaired in the energy storage branch to be repaired is first controlled to be less than the current safety value, and then the branch voltage of the energy storage branch to be repaired is controlled to be less than the branch voltage safety value. As long as the busbar of the energy storage branch does not charge the energy storage branch to be repaired during the above control process, it is sufficient.

[0128] For the purpose of simplicity of explanation, in the following embodiments, an example is given in which the energy storage branch to be repaired is first controlled to be in a no-power output state, the branch voltage of the energy storage branch to be repaired is less than the branch voltage safety value, and then the current of the energy storage sub-module to be repaired in the energy storage branch to be repaired is controlled to be less than the current safety value. However, this does not strictly limit the execution order of the various steps.

[0129] In the above step S402, there is no limitation on the method of controlling the energy storage branch to be repaired to be in a no-power output state. In some embodiments, controlling the energy storage branch to be repaired to be in a no-power output state includes:

[0130] The branch current of the energy storage branch to be repaired is controlled to be 0.

[0131] When the branch current of the energy storage branch to be repaired is 0, based on the power determination method, since there is no branch current, it can be determined that the energy storage branch to be repaired has no power output, which can make the branch current of the energy storage branch to be repaired 0, that is, there is no current output as a whole, and thus it is in a no-power output state, which can make the energy storage branch to be repaired in a maintenance preparation state to improve safety.

[0132] In some embodiments, controlling the energy storage branch to be repaired to be in a no-power output state includes:

[0133] The energy storage branch to be repaired is controlled to be in a locked state so that the branch current of the energy storage branch to be repaired is less than a preset value.

[0134] Among them, the locked state refers to the state where the energy storage branch is not working. When the energy storage branch is not working, the energy storage branch as a whole has no current output, so that the branch current of the energy storage branch to be repaired can be less than a preset value.

[0135] There is no limitation on the specific setting method of the preset value, as long as the branch current of the energy storage branch is the preset value or less than the preset value, the branch current of the energy storage branch is in a state of no power output as a whole.

[0136] Based on the solution of this embodiment, by controlling the energy storage branch to be repaired to be in a locked state, when the energy storage branch to be controlled is in a locked state, theoretically no branch current flows through the energy storage branch to be repaired, that is, there is no current output as a whole, the branch current is less than a preset value, and it is in a no-power output state. The control method is simple and convenient, and the operability is strong.

[0137] There is no limitation on the manner of controlling the energy storage branch to be repaired to be in a locked state. In some embodiments, controlling the energy storage branch to be repaired to be in a locked state includes:

[0138] A locking instruction is sent to the branch controller of the energy storage branch to be repaired, wherein the locking instruction is used to control the energy storage branch to be repaired to stop switching, so that the energy storage branch to be repaired is in a locked state.

[0139] A locking instruction refers to an instruction used to control the energy storage branch to enter a locked state. Whether the energy storage branch is in the locked state can be controlled based on the branch controller of the energy storage branch. Therefore, by sending a locking instruction to the branch controller of the energy storage branch to be repaired, the branch controller can control the energy storage branch to be repaired to stop switching, so that the energy storage branch to be repaired is in a locked state.

[0140] Therefore, when the energy storage branch to be repaired is controlled to be in a locked state, it can be achieved by sending a locking instruction to the branch controller of the energy storage branch to be repaired. The energy storage branch to be repaired can stop switching based on the locking instruction, so that the energy storage branch to be repaired is in a locked state. At this time, the branch current of the energy storage branch to be repaired is less than the preset value, that is, there is no current output as a whole, and it is in a no-power output state. The control method is simple and convenient, and the operability is strong.

[0141] In a high-voltage energy storage system, the branch controller can be a standalone controller or comprise multiple submodule controllers, with each submodule controller corresponding to at least one energy storage submodule, i.e., one submodule controller controls one or more energy storage submodules. The number of submodule controllers can be the same as the number of energy storage submodules, i.e., a one-to-one correspondence exists between each submodule controller and each energy storage submodule, with each submodule controller controlling a corresponding energy storage submodule. It should be understood that in actual technical implementations, redundant configurations may also be employed.

[0142] Taking a branch controller including a plurality of submodules as an example, the step of sending a locking instruction to the branch controller of the energy storage branch to be repaired, wherein the locking instruction is used to control the energy storage branch to be repaired to stop switching so that the energy storage branch to be repaired is in a locked state, may include:

[0143] A locking instruction is sent to the submodule controller of the energy storage submodule of the energy storage branch to be repaired, wherein the locking instruction is used to instruct the submodule controller to shut down the IGBT (Insulated Gate Bipolar Transistor) of the power module in the energy storage submodule, and the branch controller includes the submodule controller.

[0144] The locking instruction sent to the sub-module controller can be used to control the sub-module controller to shut down the IGBT of the power module in each energy storage sub-module controlled by the sub-module controller, so that the energy storage sub-module is in a locked state, and then the energy storage branch to be repaired including the energy storage sub-module is in a locked state.

[0145] The structural block diagram of the energy storage submodule in some embodiments is as follows: Figure 5 As shown, the IGBT of the power module of the energy storage submodule is turned off, specifically, Figure 5 As shown in the IGBT2, after IGBT2 is turned off, when the energy storage submodule is cascaded with other energy storage submodules through terminal 1 and terminal 2, the energy storage submodule is locked by cascading through the turned-off IGBT2.

[0146] Therefore, when a locking instruction is sent to the branch controller of the energy storage branch to be repaired to control the energy storage branch to be repaired to stop switching, the submodule controller can be specifically instructed to turn off the IGBT of the power module in the energy storage submodule. That is, by turning off the IGBT of the power module in the energy storage submodule, the energy storage submodule of the energy storage branch to be repaired can be stopped from switching, so that the branch current of the energy storage branch to be repaired is 0. The control method is simple and convenient, and the operability is strong.

[0147] In some embodiments, controlling the energy storage branch to be repaired to be in a no-power output state may include: controlling the energy storage branch to be repaired to be in a short-circuit state so that the energy storage branch to be repaired is in a no-power output state.

[0148] In some application scenarios, the energy storage submodule is provided with a switch connected in parallel to the IGBT2 of the energy storage submodule in series, such as Figure 5 As shown, the switch K in the energy storage submodule can be closed to short-circuit the IGBT2 used to connect the energy storage submodule in series, thereby controlling the energy storage branch to be repaired to be in a short-circuit state, which is simple and convenient to operate.

[0149] In some embodiments, reference Figure 6 As shown, after controlling the energy storage branch to be repaired to be in a no-power output state and before controlling the voltage of the energy storage branch to be repaired to be less than the branch voltage safety value, the method further includes:

[0150] Step S4031: Control the energy storage branch to be repaired to be in an isolated and tripped state.

[0151] The energy storage branch to be repaired is in an isolated and tripped state, meaning that the power supply to the energy storage branch to be repaired is cut off and no small current flows through it. When the energy storage branch to be repaired is in a no-power output state, the energy storage branch to be repaired as a whole has no current output. However, in actual technical scenarios, the energy storage branch to be repaired is still connected to the power supply, which may cause leakage current and affect the safety of the repair. Therefore, by isolating and tripping the energy storage branch to be repaired, the current of the energy storage branch to be repaired can be isolated and disconnected, thereby further improving the safety of the repair state.

[0152] There is no limitation on the manner of controlling the energy storage branch to be repaired to be in an isolated and tripped state. In some embodiments, controlling the energy storage branch to be repaired to be in an isolated and tripped state includes:

[0153] The isolating switch of the energy storage branch to be repaired is controlled to be in an open state.

[0154] In the energy storage branch, an isolating switch is usually provided to reduce the impact of the fault through the isolating switch when a fault occurs, or to change the system operation wiring mode through the isolating switch.

[0155] In the energy storage branch, only one isolating switch or two isolating switches may be provided. Generally, when the negative busbar of the energy storage branch is grounded, an isolating switch may be provided only on the positive busbar side of the energy storage branch to isolate the influence of the positive busbar voltage. It should be understood that when the negative busbar of the energy storage branch is grounded, isolating switches may be provided on both the positive busbar side and the negative busbar side of the energy storage branch, such as Figure 2 As shown in the figure, the isolating knife switch is the set isolating switch.

[0156] By controlling the isolating switch of the energy storage branch to be repaired to be in the open state, the energy storage branch to be repaired can be controlled to be in the isolated and open state, which can reduce the possibility of current passing through the energy storage branch to be repaired, so as to further improve the safety of maintenance. The control method is simple and convenient, does not require the introduction of additional equipment, and has strong operability.

[0157] After controlling the isolating switch of the energy storage branch to be repaired to be in an open state, the method may further include:

[0158] The isolating switch state of the isolating switch of the energy storage branch to be repaired is detected, and whether the isolating switch is correctly opened is determined according to the isolating switch state.

[0159] Among them, the method of detecting the isolating switch status of the isolating switch is not limited, as long as it can detect whether the isolating switch is in the open state. The embodiment of the present application does not impose any specific restrictions on this.

[0160] Therefore, after performing the work of opening the isolating switch of the energy storage branch to be repaired, the isolating switch status of the isolating switch of the energy storage branch to be repaired is further detected to ensure that the isolating switch of the energy storage branch to be repaired is correctly opened, so as to further improve the maintenance safety.

[0161] In some embodiments, reference Figure 7 As shown, after controlling the energy storage branch to be repaired to be in a no-power output state, and before controlling the branch voltage of the energy storage branch to be repaired to be less than the branch voltage safety value, the method may further include:

[0162] Step S4032: Control the energy storage branch to be repaired to be in a disconnected state.

[0163] The energy storage branch to be repaired is in a disconnected state, which means that the energy storage branch to be repaired is disconnected from the power supply. When the energy storage branch to be repaired is in a state of no power output, the energy storage branch to be repaired as a whole has no current output. However, in actual technical scenarios, the energy storage branch to be repaired is still connected to the power supply, and it is easy for power supply fluctuations or other conditions to cause current to flow in the energy storage branch to be repaired, affecting the safety of repair. Therefore, by disconnecting the energy storage branch to be repaired, the energy storage branch to be repaired is controlled to be in a disconnected state, so that the energy storage circuit to be repaired is in a disconnected state, reducing the possibility of current flowing due to the energy storage circuit to be repaired not being disconnected, and further improving the safety of repair.

[0164] There are various ways to control the energy storage branch to be repaired to be in a disconnected state, and several of these ways are described below with examples.

[0165] In some embodiments, controlling the energy storage branch to be repaired to be in a disconnected state includes:

[0166] The circuit breaker of the energy storage branch to be repaired is controlled to be in an open state.

[0167] A circuit breaker refers to a switching device that can close, carry and disconnect current under normal or abnormal circuit conditions. Therefore, when a circuit breaker is installed on the energy storage branch to be repaired, the current of the energy storage branch to be repaired can be disconnected by controlling the circuit breaker of the energy storage branch to be repaired to be in the open state, thereby further improving the safety of the maintenance state.

[0168] After controlling the circuit breaker of the energy storage branch to be repaired to be in the open state, the method may further include:

[0169] Detect the circuit breaker status of the circuit breaker of the energy storage branch to be repaired, and determine whether the circuit breaker is correctly opened according to the circuit breaker status.

[0170] There is no limitation on the method of detecting the circuit breaker state of the circuit breaker, as long as it can detect whether the circuit breaker is in the open state. The embodiment of the present application does not impose any specific limitation on this.

[0171] Therefore, after executing the work of controlling the circuit breaker of the energy storage branch to be repaired to be in the open state, the circuit breaker state of the circuit breaker of the energy storage branch to be repaired is further detected to ensure that the circuit breaker of the energy storage branch to be repaired is correctly opened, so as to further improve the maintenance safety.

[0172] In some embodiments, controlling the energy storage branch to be repaired to be in a disconnected state includes:

[0173] The fast switch of the energy storage branch to be repaired is controlled to be in an open state.

[0174] A fast switch is a switching device that can quickly close, carry, and interrupt current under normal or abnormal circuit conditions. In high-voltage energy storage systems, fast switches can quickly cut off fault currents in the event of a fault, with fast opening and closing speeds. Therefore, when it is necessary to control the energy storage branch under maintenance in the disconnected state, by controlling the fast switch of the energy storage branch under maintenance in the open state, the fast response speed and opening speed can not only meet the need to disconnect the energy storage branch under maintenance, improve the safety of the maintenance state, but also help improve maintenance efficiency.

[0175] After controlling the fast switch of the energy storage branch to be repaired to be in an open state, the method may further include:

[0176] The fast switching state of the fast switch of the energy storage branch to be repaired is detected, and whether the fast switch is correctly opened is determined according to the fast switching state.

[0177] There is no limitation on the method for detecting the fast switch state of the fast switch, as long as it is possible to detect whether the fast switch is in the open state. The embodiment of the present application does not impose any specific limitation on this.

[0178] Therefore, after executing the work of controlling the fast switch of the energy storage branch to be repaired to be in the open state, the fast switching state of the fast switch of the energy storage branch to be repaired is further detected to ensure that the fast switch of the energy storage branch to be repaired is correctly opened, so as to further improve the safety of maintenance.

[0179] There is no limitation on the manner of controlling the voltage of the energy storage branch to be repaired to be lower than the branch voltage safety value. Some of these implementations are described below with examples.

[0180] In some embodiments, controlling the voltage of the energy storage branch to be repaired to be less than a branch voltage safety value may include:

[0181] The voltage reduction module of the energy storage branch to be repaired is used to perform voltage reduction processing so that the voltage of the energy storage branch to be repaired is less than the branch voltage safety value.

[0182] The step-down module can also be called a step-down converter, a step-down regulator, a step-down inverter, etc., which can convert the input voltage into a lower voltage output. Among them, the setting position of the step-down module on the energy storage branch to be repaired is not limited, for example, it can be set on the side of the positive bus of the energy storage branch to be repaired. When the energy storage branch is working normally, the step-down module can be in a bypass state, or in a non-enabled state, and the energy storage branch can work normally. When the high-voltage energy storage system needs to enter the maintenance state, it is necessary to reduce the voltage of the energy storage branch to be repaired to less than the branch voltage safety value. By enabling the step-down module, the voltage of the energy storage branch to be repaired is less than the branch voltage safety value through the step-down processing of the step-down module. Among them, the specific parameter setting method of the step-down module is not limited, as long as the output voltage after the step-down module is reduced, it can be less than the branch voltage safety value.

[0183] Based on this embodiment, a step-down module can be configured for the energy storage branch. During the normal operation of the energy storage branch, the step-down module is not enabled. When it is necessary to enter the maintenance state for maintenance and it is necessary to control the voltage of the energy storage branch to be repaired to be lower than the branch voltage safety value, the step-down module is enabled to perform voltage reduction processing through the step-down module so that the voltage of the energy storage branch to be repaired is lower than the branch voltage safety value, thereby improving maintenance safety.

[0184] In other embodiments, controlling the voltage of the energy storage branch to be repaired to be less than a branch voltage safety value may include:

[0185] Control the energy storage branch to be repaired to be grounded.

[0186] Grounding the energy storage branch to be repaired means that the potential of the energy storage branch to be repaired is at the ground potential. Under normal circumstances, the ground potential is a very low potential that can meet safety requirements. Under the ground potential (ground voltage), there will be no safety problems when personnel enter. In this case, the voltage of the energy storage branch to be repaired can be made lower than the branch voltage safety value.

[0187] Based on this embodiment, since most high-voltage energy storage systems are series systems, when not grounded, the system voltage and the shell voltage of each submodule are still in a suspended state. Therefore, when it is necessary to control the voltage of the energy storage branch to be repaired to be lower than the branch voltage safety value, by controlling the grounding switch of the energy storage branch to be repaired to be closed, one or both ends of the grounding switch of the energy storage branch to be repaired can be at the ground potential, which can further improve safety and the control method is simple and convenient.

[0188] There is no limitation on the method of controlling the grounding of the energy storage branch to be repaired, as long as the energy storage branch to be repaired can be placed in a grounded state.

[0189] In some embodiments, controlling the grounding of the energy storage branch to be repaired may include:

[0190] Control the grounding switch of the energy storage branch to be repaired to close.

[0191] In a high-voltage energy storage system, a grounding switch is usually provided on the energy storage branch to ground the energy storage branch through the grounding switch when needed (such as when a fault occurs). In the energy storage branch, there may be only one grounding switch or two grounding switches. Normally, when the negative busbar of the energy storage branch is grounded, a grounding switch may be provided only on the positive busbar side of the energy storage branch to isolate the influence of the positive busbar voltage. It should be understood that when the negative busbar of the energy storage branch is grounded, grounding switches may also be provided on both the positive busbar side and the negative busbar side of the energy storage branch, such as Figure 2 As shown in the figure, the grounding knife switch is the set grounding switch.

[0192] Based on this embodiment, when it is necessary to control the grounding of the energy storage branch to be repaired, by controlling the closing of the grounding switch of the energy storage branch to be repaired, one or both ends of the grounding switch of the energy storage branch to be repaired can be at the ground potential, which can further improve safety. The control method is simple and convenient, and no additional devices are required.

[0193] After controlling the grounding switch of the energy storage branch to be repaired to be closed, the method may further include:

[0194] The grounding switch state of the grounding switch of the energy storage branch to be repaired is detected, and whether the grounding switch is correctly closed is determined according to the grounding switch state.

[0195] There is no limitation on the method of inspecting the grounding switch status of the grounding switch, as long as it is possible to detect whether the grounding switch is in the open state. The embodiment of the present application does not impose any specific limitation on this.

[0196] Therefore, after executing the work of controlling the closing of the grounding switch of the energy storage branch to be repaired, the grounding state of the grounding switch of the energy storage branch to be repaired is further detected to ensure that the grounding switch of the energy storage branch to be repaired is correctly closed, thereby further improving the safety of repair.

[0197] Among them, reference Figure 5 As shown, the energy storage submodule generally includes a connected energy storage battery 501 and a power module 502. Figure 5 As shown, there is a capacitor C in the power module 502. The capacitor C may have a high voltage, which causes current to flow in the energy storage submodule, affecting safety. Figure 8As shown, controlling the current of the energy storage submodule to be repaired in the energy storage branch to be repaired to be less than the current safety value may include:

[0198] Step S4060: Controlling the discharge of the capacitor in the power module of the energy storage submodule to be repaired, so that the current of the energy storage submodule to be repaired in the energy storage branch to be repaired is less than the current safety value.

[0199] Since in the high-voltage energy storage system, the energy storage submodule is large in size, and the capacitors in the power module of the energy storage submodule are in a high-voltage state, it is easy for current to flow in the energy storage submodule. Therefore, by controlling the discharge of the capacitors in the power module of the energy storage submodule to be repaired, the voltage of the capacitors in the power module can be reduced, so that the current of the energy storage submodule to be repaired in the energy storage branch to be repaired is less than the current safety value, allowing maintenance personnel to enter the energy storage submodule to be repaired for maintenance, so as to further ensure maintenance safety.

[0200] There are various ways to control the current of the energy storage submodule to be repaired in the energy storage branch to be repaired to be less than the current safety value. Some of these ways are described below with examples.

[0201] In some embodiments, the energy storage submodule further includes a discharge module, and the power module is connected to either the energy storage battery or the discharge module;

[0202] The controlling the discharge of the capacitor in the power module of the energy storage submodule to be repaired includes:

[0203] The power module is controlled to switch to be connected to the discharge module, so that the capacitor in the power module is discharged through the discharge module.

[0204] The discharge module is a module that can discharge the capacitor part, and the voltage on the capacitor can be released through the discharge module. Among them, the discharge module can be an independent module. When the energy storage submodule is working normally, the discharge module is in a bypass state or is not enabled, the power module is not connected to the discharge module, and the energy storage submodule works normally. When it is necessary to enter the maintenance state and control the discharge of the capacitor in the power module of the energy storage submodule to be repaired, the power module is switched to connect with the discharge module, so that the capacitor in the power module can be discharged through the discharge module.

[0205] Therefore, a special discharge module is set in the energy storage submodule, and the power module is connected to the energy storage battery and the discharge module in a selective manner. During the normal operation of the energy storage submodule, the power module is connected to the energy storage module. When it is necessary to enter the maintenance state for maintenance, the power module is disconnected from the energy storage module and switched to the discharge module. The capacitor of the power module will be discharged through the discharge module, thereby reducing the voltage of the capacitor in the power module, making the current of the energy storage submodule to be repaired in the energy storage branch to be repaired less than the current safety value, so that maintenance personnel can enter the energy storage submodule to be repaired for maintenance, so as to further improve maintenance safety.

[0206] In some embodiments, combined Figure 5 As shown, the power module includes a capacitor and a resistor; the method of controlling the discharge of the capacitor in the power module of the energy storage submodule to be repaired includes:

[0207] The connection between the energy storage battery of the energy storage submodule to be repaired and the power module is disconnected, so that the capacitor in the power module discharges to the resistance of the power module.

[0208] After the connection between the energy storage battery and the power module is disconnected, a loop is no longer formed between the energy storage battery and the power module. However, due to the presence of capacitors and resistors in the power module, the capacitors and resistors can form a loop. The capacitors discharge the resistors, causing the voltage in the capacitors to decrease.

[0209] In high-voltage energy storage systems, some energy storage submodules are provided with capacitors and resistors. Therefore, by disconnecting the connection between the energy storage battery of the energy storage submodule to be repaired and the power module, the capacitor and the resistor in the power module form a loop. Based on this loop, the capacitor of the power module will discharge the resistor of the power module, thereby reducing the voltage of the capacitor in the power module, making the current of the energy storage submodule to be repaired in the energy storage branch to be repaired less than the current safety value, allowing maintenance personnel to enter the energy storage submodule to be repaired for maintenance, so as to further ensure maintenance safety.

[0210] The method of disconnecting the connection between the energy storage battery and the power module of the energy storage submodule to be repaired is not limited. In some embodiments, Figure 5 As shown, a switch 503 can be provided between the energy storage battery and the power module. Specifically, since the energy storage submodule comprises multiple energy storage batteries connected in parallel and then connected to the power module, the switch can be provided between the parallel energy storage batteries and the power module. The type of switch is not limited. In the embodiment of the present application, the switch can be an isolating switch. Since an isolating switch can isolate small currents, it can help further improve safety.

[0211] Accordingly, in some embodiments, taking an example where an isolating switch is provided between the energy storage battery and the power module, disconnecting the connection between the energy storage battery and the power module of the energy storage submodule to be repaired may include:

[0212] Disconnect the isolation switch between the parallel energy storage battery and the power module of the energy storage submodule to be repaired.

[0213] Since there are usually multiple energy storage batteries in the energy storage submodule, and these multiple energy storage batteries are connected to the power module in parallel, when it is necessary to disconnect the energy storage batteries of the energy storage submodule to be repaired and the power module, the parallel energy storage batteries of the energy storage submodule to be repaired and the power module can be directly disconnected by disconnecting the isolation switch between the parallel energy storage batteries of the energy storage submodule to be repaired and the power module. This can put the parallel energy storage batteries of the energy storage submodule to be repaired and the power module into a disconnected state, so that the power module is disconnected from the parallel energy storage batteries, and the capacitor and the resistor in the power module form a loop. Based on this loop, the capacitor of the power module will discharge the resistor of the power module, so that the voltage of the capacitor in the power module is reduced, so that the current of the energy storage submodule to be repaired in the energy storage branch to be repaired is less than the current safety value. In addition, by disconnecting the isolation switch, a visible breakpoint can be provided, which can improve reliability.

[0214] After disconnecting the isolating switch between the parallel energy storage battery and the power module of the energy storage submodule to be repaired, the method may further include:

[0215] Detect the isolating switch status of the isolating switch between the parallel energy storage battery and the power module of the energy storage submodule to be repaired, and determine whether the isolating switch between the parallel energy storage battery and the power module is correctly opened according to the isolating switch status.

[0216] Therefore, after disconnecting the isolating switch between the parallel energy storage battery and the power module of the energy storage submodule under maintenance, the isolating switch status of the isolating switch between the parallel energy storage battery and the power module is further detected to ensure that the isolating switch between the parallel energy storage battery and the power module is correctly opened, thereby further improving maintenance safety.

[0217] As mentioned above, in the energy storage submodule, multiple energy storage batteries are connected in parallel and then connected to the power module. Each energy storage battery has a branch switch, and the opening and closing states of the branch switch can be controlled to switch whether the energy storage battery is connected. At this time, each energy storage battery can be called a parallel energy storage battery.

[0218] Accordingly, in some embodiments, disconnecting the connection between the energy storage battery and the power module of the energy storage submodule to be repaired includes:

[0219] Disconnect the branch switch of the parallel energy storage battery.

[0220] Since there are usually multiple energy storage batteries in the energy storage submodule, and these multiple energy storage batteries are connected to the power module in parallel, when it is necessary to disconnect the connection between the energy storage battery of the energy storage submodule to be repaired and the power module, the branch switch of the parallel energy storage battery can be directly disconnected to put the energy storage switch of the parallel energy storage battery into an off state, so that there is no current on the busbar of the energy storage battery, and the capacitor and the resistor in the power module form a loop. Based on this loop, the capacitor of the power module will discharge the resistor of the power module, so that the voltage of the capacitor in the power module is reduced, so that the current of the energy storage submodule to be repaired in the energy storage branch to be repaired is less than the current safety value.

[0221] When disconnecting the branch switches of the parallel energy storage batteries, the branch switches of all the energy storage batteries in the energy storage submodule can be disconnected, thereby disconnecting each energy storage battery. Alternatively, the branch switches of a portion of the parallel energy storage batteries in the energy storage submodule can be disconnected. As long as disconnecting only the branch switches of a portion of the parallel energy storage batteries allows the capacitors in the power module to discharge and the current of the energy storage submodule to be repaired to be less than the safe current value, it will be sufficient.

[0222] After disconnecting the branch switch of the parallel energy storage battery, the following steps may also be performed:

[0223] Detect the branch switch status of the branch switch of the parallel energy storage battery, and determine whether the branch switch of the parallel energy storage battery is correctly opened according to the branch switch status.

[0224] Therefore, after performing the work of disconnecting the branch switch of the parallel energy storage battery, the branch switch status of the branch switch of the parallel energy storage battery is further detected to ensure that the branch switch of the parallel energy storage battery is correctly opened, so as to further improve the maintenance safety.

[0225] In some embodiments, disconnecting the energy storage battery and the power module of the energy storage submodule to be repaired includes:

[0226] Disconnect the isolation switch between the parallel energy storage battery and the power module and the branch switch of the parallel energy storage battery.

[0227] Since there are usually multiple energy storage batteries in the energy storage submodule, and these multiple energy storage batteries are connected to the power module in parallel, when it is necessary to disconnect the energy storage battery of the energy storage submodule to be repaired and the power module, both the isolating switch between the parallel energy storage batteries of the energy storage submodule to be repaired and the power module is disconnected, and the branch switch of the parallel energy storage batteries is disconnected. Disconnecting the isolating switch not only provides a visible breakpoint, thereby improving reliability, but also eliminates current on the busbar of the energy storage battery. Through the dual control method, the capacitor and the resistor in the power module form a loop, so that based on this loop, the capacitor of the power module discharges the resistor of the power module, thereby improving the reliability of disconnecting the energy storage battery of the energy storage submodule to be repaired and the power module, and increasing the possibility of ensuring that the current of the energy storage submodule to be repaired in the energy storage branch to be repaired is less than the current safety value.

[0228] There is no limitation on the manner of grounding the housing of the energy storage submodule to be repaired. In some embodiments, grounding the housing of the energy storage submodule to be repaired includes any one of the following:

[0229] Hanging the shell of the energy storage submodule to be repaired on a grounding rod;

[0230] Connecting the housing of the energy storage submodule to be repaired to the ground wire;

[0231] Close the standby grounding switch of the energy storage submodule to be repaired.

[0232] Grounding rods, also known as grounding electrodes or grounding grids, can improve the internal conductivity of grounding conductors and reduce the external soil resistivity of grounding conductors. They are easy to construct, require little space, are environmentally friendly, have a long service life, and offer low resistance. By hooking the housing of the energy storage submodule to be repaired to the grounding rod, the housing of the energy storage submodule to be repaired can be grounded in a simple and convenient manner.

[0233] The ground wire is connected to the earth, the housing or a conductor with a reference potential of zero. Therefore, the housing of the energy storage submodule to be repaired can be grounded by connecting the housing of the energy storage submodule to be repaired to the ground wire.

[0234] In some application scenarios, the energy storage submodule is provided with a backup grounding switch. Therefore, the shell of the energy storage submodule to be repaired can be grounded by closing the backup grounding switch. The operation is simple and convenient, and no additional equipment is required.

[0235] Therefore, when it is necessary to ground the shell of the energy storage submodule to be repaired, the shell of the energy storage submodule to be repaired can be grounded by hanging the shell of the energy storage submodule to be repaired on a grounding rod, connecting the shell of the energy storage submodule to be repaired to a ground wire, closing the standby grounding switch of the energy storage submodule to be repaired, etc., so that when actually performing the shell grounding operation, it can be selected according to the needs of the scene, which has strong flexibility and operability.

[0236] Based on the above-mentioned embodiments, some specific examples are given below for illustration. Figure 9 As shown, when the high-voltage energy storage system needs to be repaired, the high-voltage energy storage system can be put into a repair state in the following manner to repair the high-voltage energy storage system.

[0237] Combine Figure 9 As shown in the figure, when the high-voltage energy storage system needs to be repaired, a locking command is first sent to the energy storage branch to be repaired through the valve control system. The energy storage branch stops switching and the IGBT of the energy storage submodule is turned off. At this time, the branch current of the energy storage branch is less than the preset value. Theoretically, the branch current of the energy storage branch is 0, and the energy storage branch as a whole is in a locked state.

[0238] When the energy storage branch is locked, leakage current may occur. By controlling the fast switch of the energy storage branch under maintenance to the open state, the system leakage current of the energy storage branch under maintenance can be quickly disconnected, and a break visible in the air can be provided. After controlling the fast switch to the open state, the state of the fast switch of the energy storage branch can also be checked to determine whether it is in the open state to ensure that the fast switch is correctly opened.

[0239] The fast switch can quickly disconnect the system leakage current of the energy storage branch under maintenance, and further disconnect the isolating switch of the energy storage branch under maintenance to ensure that no current flows through the energy storage branch. After disconnecting the isolating switch, the isolating switch of the energy storage branch under maintenance is also checked to see if it is in the open state to ensure that it is correctly opened.

[0240] The grounding switch of the energy storage branch under maintenance is controlled to close, ensuring that the branch voltage of the energy storage branch is below the safe branch voltage value, for example, at zero potential. The grounding switch of the energy storage branch can be located adjacent to the disconnector and close to the energy storage branch. Because the energy storage branch contains energy storage submodules connected in series, if ungrounded, the branch voltage and the housing voltage of each submodule remain suspended, posing a significant risk to maintenance personnel. Closing the grounding switch of the energy storage branch sets the ground reference potential, ensuring that one or both ends of the grounding switch (depending on the system configuration) are at zero potential. After closing the grounding switch of the energy storage branch under maintenance, a status check can be performed to verify that the grounding switch is closed to ensure proper closing.

[0241] After performing the above operations, the whole machine enters the maintenance preparation state, and the energy storage submodule that needs to be repaired (i.e., the energy storage submodule to be repaired) can be operated to put the submodule to be repaired into the maintenance state to meet the maintenance requirements.

[0242] Take the example of an isolating switch between the parallel energy storage battery and the power module, and disconnect the isolating switch between the parallel energy storage battery and the power module. The isolating switch is set at the connection position between the power module and the parallel energy storage battery. Figure 5 As shown, since there are capacitors in the power module connected in parallel with the energy storage battery, the capacitors need to be discharged to ensure maintenance safety. By disconnecting the isolating switch between the parallel energy storage battery and the power module, the capacitors in the power module of the energy storage submodule can be discharged to the resistor, so that the current in the energy storage submodule is less than the current safety value, that is, the leakage current of the energy storage submodule is less than the current safety value, so that the energy storage submodule does not have the common leakage current caused by the battery. After disconnecting the isolating switch between the parallel energy storage battery and the power module, the state of the isolating switch can also be detected to detect whether the isolating switch is in the open state to ensure that it is correctly opened.

[0243] Subsequently, the housing of the energy storage submodule to be repaired is grounded, reducing the voltage of the housing to ground potential. After grounding the housing of the energy storage submodule to be repaired, the housing (platform) voltage of the repair submodule can be further measured to detect whether the housing voltage is at ground potential or zero potential, thereby ensuring repair safety.

[0244] After the above operations, the operator can intervene in the energy storage submodule of the high-voltage energy storage system on site for maintenance.

[0245] It should be understood that, although the various steps in the flowcharts involved in the various embodiments described above are displayed in sequence according to the instructions of the arrows, these steps are not necessarily executed in sequence in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the flowcharts involved in the various embodiments described above can include multiple steps or multiple stages, and these steps or stages are not necessarily executed and completed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of steps or stages in other steps.

[0246] Based on the same inventive concept, an embodiment of the present application further provides a device for controlling a high-voltage energy storage system to enter a maintenance state, which is used to implement the aforementioned method for controlling a high-voltage energy storage system to enter a maintenance state. The solution provided by this device is similar to the solution described in the aforementioned method. Therefore, the specific limitations of one or more embodiments of the device for controlling a high-voltage energy storage system to enter a maintenance state provided below can be found in the aforementioned method for controlling a high-voltage energy storage system to enter a maintenance state, and will not be repeated here.

[0247] In one embodiment, Figure 10 As shown, a device for controlling a high-voltage energy storage system to enter a maintenance state is provided, wherein the high-voltage energy storage system includes at least one energy storage branch, and the energy storage branch includes a plurality of cascaded energy storage submodules; wherein the device includes: a branch control module 101 and a submodule control module 102, wherein:

[0248] The branch control module 101 is used to control the energy storage branch to be repaired to be in a no-power output state, and to control the voltage of the energy storage branch to be repaired to be less than a branch voltage safety value;

[0249] The submodule control module 102 is used to control the current safety value of the energy storage submodule to be repaired in the energy storage branch to be repaired, and to ground the shell of the energy storage submodule to be repaired.

[0250] In some embodiments, the branch control module 101 is used to control the energy storage branch to be repaired to be in a locked state, so that the branch current of the energy storage branch to be repaired is less than a preset value.

[0251] In some embodiments, the branch control module 101 is further used to control the energy storage branch to be repaired to be in an isolated and disconnected state after the energy storage branch to be repaired is in a no-power output state, and before the voltage of the energy storage branch to be repaired is controlled to be less than the branch voltage safety value.

[0252] In some embodiments, the branch control module 101 is further used to control the energy storage branch to be repaired to be in a no-power output state, and before the branch voltage of the energy storage branch to be repaired is controlled to be less than the branch voltage safety value, and also includes: controlling the energy storage branch to be repaired to be in a disconnected state.

[0253] In some embodiments, the branch control module 101 is further configured to control the fast switch of the energy storage branch to be repaired to be in an open state, so as to control the energy storage branch to be repaired to be in a disconnected state.

[0254] In some embodiments, the branch control module 101 is configured to perform voltage reduction processing through a voltage reduction module of the energy storage branch to be repaired, so that the voltage of the energy storage branch to be repaired is less than a branch voltage safety value.

[0255] In some embodiments, the branch control module 101 is used to control the energy storage branch to be repaired to be grounded, so as to control the voltage of the energy storage branch to be repaired to be lower than the branch voltage safety value.

[0256] In some embodiments, the energy storage submodule includes an energy storage battery and a power module, and the submodule control module 102 is used to control the discharge of the capacitor in the power module of the energy storage submodule to be repaired so that the current of the energy storage submodule to be repaired in the energy storage branch to be repaired is less than the current safety value.

[0257] In some embodiments, the energy storage submodule further includes a discharge module, and the power module is selectively connected to either the energy storage battery or the discharge module; the submodule control module 102 is used to control the power module to switch to connection with the discharge module so that the capacitor in the power module is discharged through the discharge module.

[0258] In some embodiments, the power module includes a capacitor and a resistor; the submodule control module 102 is used to disconnect the connection between the energy storage battery of the energy storage submodule to be repaired and the power module, so that the capacitor in the power module discharges to the resistor of the power module.

[0259] In some embodiments, the submodule control module 102 is configured to disconnect the isolation switch between the parallel energy storage battery and the power module and the branch switch of the parallel energy storage battery to disconnect the connection between the energy storage battery and the power module of the energy storage submodule to be repaired.

[0260] In some embodiments, the submodule control module 102 is configured to ground the housing of the energy storage submodule to be repaired by any one of the following methods:

[0261] Hanging the shell of the energy storage submodule to be repaired on a grounding rod;

[0262] Connecting the housing of the energy storage submodule to be repaired to the ground wire;

[0263] Close the standby grounding switch of the energy storage submodule to be repaired.

[0264] Each module in the aforementioned apparatus for controlling the high-voltage energy storage system to enter a maintenance state may be implemented in whole or in part through software, hardware, or a combination thereof. Each module may be embedded in or independent of a processor within a computer device in hardware form, or may be stored in a computer device memory in software form, so that the processor can call and execute the corresponding operations of each module.

[0265] In one embodiment, a computer device is provided. The computer device may be a server, and its internal structure diagram may be as follows: Figure 11 As shown. The computer device includes a processor, a memory and a network interface connected via a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store data related to controlling the high-voltage energy storage system to enter a maintenance state, such as the above-mentioned processing logic for controlling the high-voltage energy storage system to enter a maintenance state, etc. The network interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a method for controlling a high-voltage energy storage system to enter a maintenance state is implemented.

[0266] Those skilled in the art will understand that Figure 11 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0267] In one embodiment, a computer device is provided, including a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, the steps of the method for controlling a high-voltage energy storage system to enter a maintenance state in any of the embodiments described above are implemented.

[0268] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the method for controlling a high-voltage energy storage system to enter a maintenance state in any of the embodiments described above is implemented.

[0269] In one embodiment, a computer program product is provided, including a computer program, which, when executed by a processor, implements the method of controlling a high-voltage energy storage system to enter a maintenance state in any of the above embodiments.

[0270] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the above-mentioned embodiments. In particular, any reference to memory, database, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The databases involved in the various embodiments provided herein may include at least one of a relational database and a non-relational database. Non-relational databases may include, but are not limited to, distributed databases based on blockchains. The processors involved in the various embodiments provided herein may be, but are not limited to, general-purpose processors, central processing units (CPUs), graphics processing units (GPUs), digital signal processors (DSPs), programmable logic devices (PLDs), data processing logic devices based on quantum computing, and the like.

[0271] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0272] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A method for controlling a high-voltage energy storage system to enter a maintenance state, wherein the high-voltage energy storage system includes at least one energy storage branch, and the energy storage branch includes a plurality of cascaded energy storage submodules; characterized in that: The method comprises: Control the energy storage branch to be repaired to be in a no-power output state; Controlling the branch voltage of the energy storage branch to be repaired to be less than a branch voltage safety value; The current of the energy storage submodule to be repaired in the energy storage branch to be repaired is controlled to be less than a current safety value; and the shell of the energy storage submodule to be repaired is grounded.

2. The method according to claim 1, characterized in that The step of controlling the energy storage branch to be repaired to be in a no-power output state includes: The energy storage branch to be repaired is controlled to be in a locked state so that the branch current of the energy storage branch to be repaired is less than a preset value.

3. The method according to claim 1 or 2, characterized in that After controlling the energy storage branch to be repaired to be in a no-power output state and before controlling the voltage of the energy storage branch to be repaired to be less than a branch voltage safety value, the method further includes: The energy storage branch to be repaired is controlled to be in an isolated and open state.

4. The method according to any one of claims 1 to 3, characterized in that After controlling the energy storage branch to be repaired to be in a no-power output state and before controlling the branch voltage of the energy storage branch to be repaired to be less than a branch voltage safety value, the method further includes: The energy storage branch to be repaired is controlled to be in a disconnected state.

5. The method according to claim 4, characterized in that The controlling the energy storage branch to be repaired to be in a disconnected state includes: The fast switch of the energy storage branch to be repaired is controlled to be in an open state.

6. The method according to any one of claims 1 to 5, characterized in that The controlling the voltage of the energy storage branch to be repaired to be less than a branch voltage safety value includes: The voltage reduction module of the energy storage branch to be repaired is used to perform voltage reduction processing so that the voltage of the energy storage branch to be repaired is less than the branch voltage safety value.

7. The method according to any one of claims 1 to 5, characterized in that The controlling the voltage of the energy storage branch to be repaired to be less than a branch voltage safety value includes: Control the energy storage branch to be repaired to be grounded.

8. The method according to any one of claims 1 to 7, characterized in that The energy storage submodule includes an energy storage battery and a power module, and the controlling the current of the energy storage submodule to be repaired in the energy storage branch to be repaired to be less than the current safety value includes: The capacitor in the power module of the energy storage submodule to be repaired is controlled to discharge, so that the current of the energy storage submodule to be repaired in the energy storage branch to be repaired is less than the current safety value.

9. The method according to claim 8, characterized in that The energy storage submodule further includes a discharge module, and the power module is connected to either the energy storage battery or the discharge module; The controlling the discharge of the capacitor in the power module of the energy storage submodule to be repaired includes: The power module is controlled to switch to be connected to the discharge module, so that the capacitor in the power module is discharged through the discharge module.

10. The method according to claim 8, characterized in that The power module includes a capacitor and a resistor; The controlling the discharge of the capacitor in the power module of the energy storage submodule to be repaired includes: The connection between the energy storage battery of the energy storage submodule to be repaired and the power module is disconnected, so that the capacitor in the power module discharges to the resistance of the power module.

11. The method according to claim 10, characterized in that Disconnecting the connection between the energy storage battery and the power module of the energy storage submodule to be repaired includes: Disconnect the isolation switch between the parallel energy storage battery and the power module and the branch switch of the parallel energy storage battery.

12. The method according to any one of claims 1 to 11, characterized in that Grounding the housing of the energy storage submodule to be repaired includes any one of the following: Hanging the shell of the energy storage submodule to be repaired on a grounding rod; Connecting the housing of the energy storage submodule to be repaired to the ground wire; Close the standby grounding switch of the energy storage submodule to be repaired.

13. A device for controlling a high-voltage energy storage system to enter a maintenance state, wherein the high-voltage energy storage system comprises at least one energy storage branch, wherein the energy storage branch comprises a plurality of cascaded energy storage submodules; The device includes a branch control module and a submodule control module: The branch control module is used to control the energy storage branch to be repaired to be in a no-power output state, and to control the voltage of the energy storage branch to be repaired to be less than a branch voltage safety value; The submodule control module is used to control the current safety value of the energy storage submodule to be repaired in the energy storage branch to be repaired, and to ground the shell of the energy storage submodule to be repaired.

14. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 12 are implemented.

15. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 12 are implemented.

16. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 12 are implemented.

Images