A method and device for storing high pressure in an energy storage system and an energy storage system

Abstract

The embodiment of the present invention provides a method, device and system for lowering high voltage in an energy storage system. The method includes: obtaining a lower high voltage signal; responding to the lower high voltage signal, sequentially detecting the branch current in M ​​preset cycles within a preset time period; if the branch current detected in the Nth preset cycle is less than or equal to the preset current value, then stopping the detection, and determining to generate a first contactor disconnection signal based on the detected branch current in the Nth preset cycle; if the branch current detected in the M preset cycles is greater than the preset current value, then determining to preferentially generate a circuit breaker disconnection signal, and then generating a second contactor disconnection signal. The embodiment of the present invention does not require excessive human operation and can be completed with one click. In an abnormal situation, if the detected branch current cannot be reduced (that is, the branch current detected in the M preset cycles is greater than the preset current value), the circuit breaker is directly disconnected, which can avoid the impact on the contactor in the current-carrying circuit and extend the service life of the contactor.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of energy storage systems, and specifically to a method and device for storing high voltage in an energy storage system, and an energy storage system. Background Art

[0002] The current high-voltage lowering process mainly uses an isolating switch in the junction box. When the high voltage needs to be lowered, the master control directly outputs a disconnection command to the high-voltage box branch circuit breaker to execute the tripping, and then disconnects the main positive contactor and the main negative contactor in turn; or directly outputs a disconnection command to the high-voltage box contactor, disconnecting the main positive contactor and the main negative contactor in turn. Although this method only disconnects the contactor, in abnormal circumstances, directly disconnecting the contactor when there is a large current will greatly affect the life of the contactor. If the contacts are sticky, there are safety hazards. Summary of the invention

[0003] The embodiments of the present invention provide a method, device and energy storage system for reducing high voltage in an energy storage system, which are used to solve the technical problem that although the current high voltage reduction process only disconnects the contactor, under abnormal circumstances, directly disconnecting the contactor when there is a large current will greatly affect the life of the contactor, and if the contacts are stuck, there will be safety hazards.

[0004] In a first aspect, an embodiment of the present invention provides a high-voltage method for an energy storage system, comprising:

[0005] Get the lower high voltage signal;

[0006] In response to the lower high-voltage signal, the branch currents in M ​​preset cycles within a preset time period are detected in sequence, where M is an integer greater than or equal to 1, and the branch current is the current of the branch where the contactor is located, and the contactor includes a main negative contactor and a main positive contactor;

[0007] If it is detected that the branch current in the Nth preset cycle is less than or equal to the preset current value, the detection is stopped, and according to the detected branch current in the Nth preset cycle, a first contactor disconnection signal is determined to be generated, where N is an integer greater than or equal to 1 and less than or equal to M, and the first contactor disconnection signal is used to indicate disconnection of the contactor;

[0008] If it is detected that the branch currents within M preset cycles are all greater than the preset current value, it is determined to preferentially generate a circuit breaker disconnection signal, and then generate a second contactor disconnection signal, wherein the circuit breaker disconnection signal is used to indicate disconnection of the circuit breaker, and the second contactor disconnection signal is used to indicate disconnection of the contactor.

[0009] In a possible implementation, the first contactor disconnection signal includes a first main negative disconnection signal and a first main positive disconnection signal, or a second main positive disconnection signal and a second main negative disconnection signal;

[0010] If it is detected that the branch current in the Nth preset cycle is less than or equal to the preset current value, the detection is stopped, and according to the detected branch current in the Nth preset cycle, a first contactor disconnection signal is determined to be generated, including:

[0011] If it is detected that the branch current in the Nth preset cycle is less than or equal to the preset current value, the detection is stopped, and the energy storage system is in a charging state. According to the detected branch current in the Nth preset cycle, it is determined to preferentially generate a first main negative disconnection signal, and then generate a first main positive disconnection signal, wherein the first main negative disconnection signal and the first main positive disconnection signal are used to indicate disconnection of the main negative contactor and disconnection of the main positive contactor, respectively;

[0012] or

[0013] If it is detected that the branch current in the Nth preset cycle is less than or equal to the preset current value, the detection is stopped, and according to the detected branch current in the Nth preset cycle, a first contactor disconnection signal is determined to be generated, including:

[0014] If it is detected that the branch current in the Nth preset cycle is less than or equal to the preset current value, the detection is stopped and the energy storage system is in a discharging state. According to the detected branch current in the Nth preset cycle, it is determined to preferentially generate the first main positive disconnect signal and then generate the first main negative disconnect signal. The first main positive disconnect signal and the first main negative disconnect signal are used to indicate the disconnection of the main positive contactor and the disconnection of the main negative contactor, respectively.

[0015] In a possible implementation, the second contactor disconnection signal includes: a third main positive disconnection signal and a third main negative disconnection signal, and the third main positive disconnection signal and the third main negative disconnection signal are used to indicate disconnection of the main positive contactor and the main negative contactor, respectively.

[0016] In a possible implementation, the preset time period is 2 seconds, and the preset period is 100 ms.

[0017] In a second aspect, an embodiment of the present invention provides a lower high-voltage device for an energy storage system, comprising:

[0018] An acquisition unit, used for acquiring a lower high voltage signal;

[0019] A detection unit, configured to respond to the lower high voltage signal and sequentially detect branch currents in M ​​preset cycles within a preset time period, where M is an integer greater than or equal to 1, and the branch current is the current of the branch where the contactor is located, and the contactor includes a main negative contactor and a main positive contactor;

[0020] a first determining unit, configured to stop detecting if it is detected that the branch current in the Nth preset period is less than or equal to a preset current value, and determine to generate a first contactor disconnection signal according to the detected branch current in the Nth preset period, where N is an integer greater than or equal to 1 and less than or equal to M, and the contactor disconnection signal is used to indicate disconnection of the contactor; or

[0021] The second determination unit is used to determine that a circuit breaker disconnection signal is generated first, and then a second contactor disconnection signal is generated if it is detected that the branch currents within M preset cycles are all greater than a preset current value. The circuit breaker disconnection signal is used to indicate the disconnection of the circuit breaker, and the second contactor disconnection signal is used to indicate the disconnection of the contactor.

[0022] In a possible implementation, the first contactor disconnection signal includes a first main negative disconnection signal and a first main positive disconnection signal, or a second main positive disconnection signal and a second main negative disconnection signal;

[0023] The first determining unit is specifically configured to:

[0024] If it is detected that the branch current in the Nth preset cycle is less than or equal to the preset current value, the detection is stopped, and the energy storage system is in a charging state. According to the detected branch current in the Nth preset cycle, it is determined to preferentially generate a first main negative disconnection signal, and then generate a first main positive disconnection signal, wherein the first main negative disconnection signal and the first main positive disconnection signal are used to indicate disconnection of the main negative contactor and disconnection of the main positive contactor, respectively;

[0025] or

[0026] If it is detected that the branch current in the Nth preset cycle is less than or equal to the preset current value, the detection is stopped and the energy storage system is in a discharging state. According to the detected branch current in the Nth preset cycle, it is determined to preferentially generate the first main positive disconnect signal and then generate the first main negative disconnect signal. The first main positive disconnect signal and the first main negative disconnect signal are used to indicate the disconnection of the main positive contactor and the disconnection of the main negative contactor, respectively.

[0027] In a possible implementation, the second contactor disconnection signal includes: a third main positive disconnection signal and a third main negative disconnection signal, and the third main positive disconnection signal and the third main negative disconnection signal are used to indicate disconnection of the main positive contactor and the main negative contactor, respectively.

[0028] In a third aspect, an embodiment of the present invention provides an energy storage system, including:

[0029] The lower high-voltage device of the energy storage system is the lower high-voltage device of the energy storage system described in the second aspect;

[0030] A main negative contactor, used to disconnect according to a first contactor disconnection signal from a lower high-voltage device of the energy storage system; or disconnect according to a second contactor disconnection signal from a lower high-voltage device of the energy storage system;

[0031] A main positive contactor, used to disconnect according to a first contactor disconnection signal from a lower high-voltage device of the energy storage system; or disconnect according to a second contactor disconnection signal from a lower high-voltage device of the energy storage system;

[0032] The circuit breaker is used to disconnect according to the circuit breaker disconnection signal from the high-voltage device under the energy storage system.

[0033] In a possible implementation, the first contactor disconnection signal includes a first main negative disconnection signal and a first main positive disconnection signal, or a second main positive disconnection signal and a second main negative disconnection signal;

[0034] The main negative contactor is specifically used to preferentially disconnect according to the first main negative disconnect signal when the energy storage system is in a charging state;

[0035] The main positive contactor is specifically used to disconnect according to the first main positive disconnection signal after the main negative contactor is disconnected when the energy storage system is in a charging state;

[0036] or

[0037] The main positive contactor is specifically used to preferentially disconnect according to the second main positive disconnect signal when the energy storage system is in a discharging state;

[0038] The main negative contactor is specifically used to disconnect according to the second main negative disconnection signal after the main positive contactor is disconnected when the energy storage system is in a discharging state.

[0039] In a possible implementation, the second contactor disconnection signal includes: a third main positive disconnection signal and a third main negative disconnection signal;

[0040] The circuit breaker is specifically used to preferentially disconnect according to the circuit breaker disconnection signal;

[0041] The main positive contactor is specifically used to disconnect according to the third main positive disconnect signal after the circuit breaker is disconnected;

[0042] The main negative contactor is specifically used to be disconnected according to the third main negative disconnection signal after the circuit breaker is disconnected.

[0043] The embodiments of the present invention disclose the following technical effects:

[0044] The embodiment of the present invention does not require excessive human operation and can be completed with one click. In abnormal circumstances, if the detected branch current cannot be reduced (i.e., the branch current detected in M ​​preset cycles is greater than the preset current value), the circuit breaker is directly disconnected to avoid the impact on the contactor in the current-carrying line and extend the service life of the contactor; after the high-voltage signal is sent under the master control, other actions are controlled by the master control to avoid problems such as long communication time, communication loss, and communication lag during the signal interaction process.

[0045] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0047] Figure 1 A schematic diagram of a process flow of a high-voltage method for an energy storage system provided by an embodiment of the present invention;

[0048] Figure 2 A schematic block diagram of an energy storage system provided in an embodiment of the present invention;

[0049] Figure 3 Another schematic diagram of a high-voltage method for an energy storage system provided by an embodiment of the present invention

[0050] Figure 4 A schematic block diagram of a lower high-voltage device of an energy storage system provided by an embodiment of the present invention;

[0051] Figure 5 Another schematic block diagram of an energy storage system provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0052] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0053] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0054] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0055] The word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrases "if determining" or "if monitoring (stated condition or event)" may be interpreted as "when determining" or "in response to determining" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)", depending on the context.

[0056] The current high-voltage lowering process mainly uses an isolating switch in the junction box. When the high voltage needs to be lowered, the master control directly outputs a disconnection command to the high-voltage box branch circuit breaker to execute the tripping, and then disconnects the main positive contactor and the main negative contactor in turn; or directly outputs a disconnection command to the high-voltage box contactor, disconnecting the main positive contactor and the main negative contactor in turn. Although this method only disconnects the contactor, in abnormal circumstances, directly disconnecting the contactor when there is a large current will greatly affect the life of the contactor. If the contacts are sticky, there are safety hazards.

[0057] In view of this, an embodiment of the present invention provides a method for reducing high pressure in an energy storage system. The flow chart is as follows: Figure 1 The process diagram includes:

[0058] Step 101: Obtain a lower high voltage signal.

[0059] Step 102: In response to the lower high voltage signal, the branch currents in M ​​preset cycles within a preset time period are detected in sequence, where M is an integer greater than or equal to 1, and the branch current is the current of the branch where the contactor is located, and the contactor includes a main negative contactor and a main positive contactor.

[0060] Step 103: If it is detected that the branch current in the Nth preset cycle is less than or equal to the preset current value, the detection is stopped, and based on the detected branch current in the Nth preset cycle, a first contactor disconnection signal is generated, where N is an integer greater than or equal to 1 and less than or equal to M, and the first contactor disconnection signal is used to indicate disconnection of the contactor.

[0061] Step 104: If it is detected that the branch currents within M preset cycles are all greater than the preset current value, it is determined to preferentially generate a circuit breaker disconnection signal, and then generate a second contactor disconnection signal. The circuit breaker disconnection signal is used to indicate disconnection of the circuit breaker, and the second contactor disconnection signal is used to indicate disconnection of the contactor.

[0062] The following is a detailed description of each step in the above process and the effects that can be further produced in conjunction with the embodiments of the present invention. It should be noted that the "first" and "second" and other limitations involved in the embodiments of the present invention do not have limitations in terms of size, order and quantity, and are only used to distinguish them in name, for example, "first contactor disconnection signal" and "second contactor disconnection signal" are used to distinguish two different contactor disconnection signals.

[0063] First, the above step 101, namely “obtaining the lower high voltage signal” is described in detail in conjunction with an embodiment of the present invention.

[0064] In the embodiment of the present invention, if the battery array management unit (BAU) layer appears an energy management system (EMS) power-on remote control command, a display control local signal, or a system serious alarm, etc., it can trigger the following Figure 2 The general control (also known as display control) in the energy storage system shown sends a low-voltage signal to the main control. The main control can obtain the low-voltage signal from the general control.

[0065] The above step 102, i.e., "in response to the lower high voltage signal, sequentially detecting the branch currents in M ​​preset cycles within a preset time period, where M is an integer greater than or equal to 1, and the branch current is the current of the branch where the contactor is located, and the contactor includes a main negative contactor and a main positive contactor" is described in detail below in conjunction with an embodiment of the present invention.

[0066] In the embodiment of the present invention, the preset time period is divided into M preset cycles. After the master controller obtains the lower high voltage signal sent by the master controller, the battery cluster unit (BCU) layer detects the branch currents in the M preset cycles within the preset time period in response to the lower high voltage signal. For example, the master controller performs the following steps: Figure 2 The Hall sensor (HALL) in the energy storage system shown detects the branch current within M preset cycles within a preset time period. The branch current is the current of the branch where the contactor is located, and the contactor includes a main negative contactor (see Figure 2 Main negative KM) and main positive contactor (see Figure 2 The main positive KM in it).

[0067] Exemplarily, the preset time period is 2s, and the preset period is 100ms.

[0068] The above step 103, i.e., "if it is detected that the branch current in the Nth preset cycle is less than or equal to the preset current value, the detection is stopped, and based on the detected branch current in the Nth preset cycle, a first contactor disconnection signal is generated, where N is an integer greater than or equal to 1 and less than or equal to M, and the first contactor disconnection signal is used to indicate disconnection of the contactor" is described in detail below in conjunction with an embodiment of the present invention.

[0069] In an embodiment of the present invention, in step 102, when the main control sequentially detects branch currents in M ​​preset cycles within a preset time period, if the detected branch current in the Nth preset cycle is less than or equal to the preset current value, the detection is stopped, and the BCU layer determines to generate a first contactor disconnection signal based on the detected branch current in the Nth preset cycle.

[0070] It can be understood that the first contactor disconnection signal includes a first main negative disconnection signal and a first main positive disconnection signal, or the first contactor disconnection signal includes a second main positive disconnection signal and a second main negative disconnection signal.

[0071] It should be noted that if the main control detects that the branch current in the Nth preset cycle is less than or equal to the preset current value, the detection is stopped, and the energy storage system is in a charging state. Then, the BCU layer determines to prioritize the generation of the first main negative disconnect signal based on the detected branch current in the Nth preset cycle, and sends it to the main negative contactor. After detecting that the main negative contactor is disconnected, the first main positive disconnect signal is generated and sent to the main positive contactor. The first main negative disconnect signal and the first main positive disconnect signal are used to indicate the disconnection of the main negative contactor and the disconnection of the main positive contactor, respectively. In other words, the main negative contactor will first obtain the first main negative disconnect signal from the main control and disconnect first. The main positive contactor will then obtain the first main positive disconnect signal from the main control and disconnect. Alternatively, if the main control detects that the branch current in the Nth preset cycle is less than or equal to the preset current value, the detection is stopped, and the energy storage system is in a discharging state. Then, the BCU layer determines to give priority to generating the first main positive disconnect signal based on the detected branch current in the Nth preset cycle, and sends it to the main positive contactor. After detecting that the main positive contactor is disconnected, the first main negative disconnect signal is generated and sent to the main negative contactor. The first main positive disconnect signal and the first main negative disconnect signal are used to indicate disconnecting the main positive contactor and disconnecting the main negative contactor, respectively. In other words, the main positive contactor will give priority to obtaining the second main positive disconnect signal from the main control and disconnect first. The main negative contactor will then obtain the second main negative disconnect signal from the main control and disconnect.

[0072] The above step 104 is described below in conjunction with an embodiment of the present invention, i.e., "if it is detected that the branch currents within M preset cycles are all greater than the preset current value, it is determined to preferentially generate a circuit breaker disconnection signal, and then generate a second contactor disconnection signal, the circuit breaker disconnection signal being used to indicate disconnection of the circuit breaker (such as Figure 2 The second contactor disconnection signal is used to indicate the disconnection of the contactor” is described in detail.

[0073] In an embodiment of the present invention, the second contactor disconnect signal includes: a third main positive disconnect signal and a third main negative disconnect signal. The third main positive disconnect signal and the third main negative disconnect signal are used to indicate the disconnection of the main positive contactor and the main negative contactor, respectively. Specifically, if the main control detects that the branch currents within M preset cycles are all greater than the preset current value, the BCU layer determines to prioritize the generation of a circuit breaker disconnect signal, which is sent to the circuit breaker. After detecting that the circuit breaker is disconnected, the third main positive disconnect signal and the third main negative disconnect signal are generated, which are sent to the main positive contactor and the main negative contactor, respectively. In other words, the circuit breaker will preferentially obtain the circuit breaker disconnect signal from the main control and disconnect preferentially. The main positive contactor and the main negative contactor obtain the third main positive disconnect signal and the third main negative disconnect signal respectively later, and then disconnect.

[0074] As can be seen from the above content, the embodiment of the present invention does not require excessive human operation and can be completed with one click. In abnormal circumstances, if the detected branch current cannot be reduced (that is, the branch current detected in M ​​preset cycles is greater than the preset current value), the circuit breaker is directly disconnected to avoid the impact on the contactor in the current-carrying line and extend the service life of the contactor; after the high-voltage signal is sent under the master control, other actions are controlled by the main control to avoid problems such as long communication time, communication loss, and communication lag during the signal interaction process.

[0075] According to an embodiment of another aspect, a method for lowering high voltage of an energy storage system is provided. Figure 3 A schematic flow chart of a method for performing a high-voltage operation of an energy storage system according to an embodiment is shown. The schematic flow chart includes:

[0076] Step 301: Determine whether there is an EMS power-off remote control command, a display control local signal or a system serious warning.

[0077] In the embodiment of the present invention, it is determined

[0078] Step 302: If yes, trigger the master control to send a high voltage signal to the main control.

[0079] In the embodiment of the present invention, after executing step 302, step 304 is executed.

[0080] Step 303: If not, the high pressure process is not executed.

[0081] Step 304: sequentially detecting branch currents in M ​​preset periods within a preset time period.

[0082] In the embodiment of the present invention, the specific implementation process of step 304 is similar to the specific implementation process of step 102, and will not be repeated here.

[0083] Step 305: Determine whether the branch current detected in the Nth preset period is less than or equal to the preset current value.

[0084] In the embodiment of the present invention, if it is detected that the branch current in the Nth preset period is less than or equal to the preset current value, step 309 is executed. Otherwise, steps 306 to 308 are executed.

[0085] Step 306: Detect that the branch currents in M ​​preset periods are all greater than the preset current value.

[0086] Step 307: Output a circuit breaker disconnection signal to detect whether the circuit breaker is disconnected successfully.

[0087] In an embodiment of the present invention, if it is detected that the branch currents within M preset cycles are all greater than the preset current value, a circuit breaker disconnection signal is output. After detecting that the circuit breaker is disconnected successfully (exemplarily, the circuit breaker is tripped successfully), a third main positive disconnection signal and a third main negative disconnection signal are output.

[0088] Step 308: Disconnect the main positive contactor and the main negative contactor.

[0089] In the embodiment of the present invention, the main positive contactor and the main negative contactor are disconnected according to the third main positive disconnection signal and the third main negative disconnection signal in step 307 .

[0090] Step 309: Determine whether the battery is in a charging state.

[0091] In the embodiment of the present invention, if it is determined that the energy storage system is in a charging state, step 310 and step 311 are executed. If it is determined that the energy storage system is in a discharging state, step 312 and step 313 are executed.

[0092] Step 310: Open the main negative contactor.

[0093] In the embodiment of the present invention, if it is determined that the energy storage system is in a charging state, the main control first sends a first main negative disconnection signal to the main negative contactor. The main negative contactor disconnects after receiving the first main negative disconnection signal.

[0094] Step 311: Disconnect the main positive contactor.

[0095] In the embodiment of the present invention, after the main control determines that the main negative contactor is disconnected, it sends the first main positive disconnection signal to the main positive contactor. The main positive contactor disconnects after receiving the first main positive disconnection signal.

[0096] In the embodiment of the present invention, after the master control determines that the main negative contactor is disconnected, it delays for 1 second before sending the first main positive disconnection signal to the main positive contactor.

[0097] Step 312: Open the main positive contactor.

[0098] If it is determined that the energy storage system is in a discharging state, the main control first sends a second main positive disconnection signal to the main positive contactor. The main positive contactor disconnects after receiving the second main positive disconnection signal.

[0099] Step 313: Disconnect the main negative contactor.

[0100] In the embodiment of the present invention, after the main control determines that the main positive contactor is disconnected, it sends a second main negative disconnection signal to the main negative contactor. The main negative contactor disconnects after receiving the second main negative disconnection signal.

[0101] In the embodiment of the present invention, after the master control determines that the main positive contactor is disconnected, it delays for 1 second before sending the second main negative disconnection signal to the main negative contactor.

[0102] According to an embodiment of another aspect, a lower high-voltage device of an energy storage system is provided. Figure 4 A schematic block diagram of a lower high-voltage device of the energy storage system according to an embodiment is shown, and the device can be arranged at Figure 2 The main control in the energy storage system shown in the figure. Figure 4 As shown, the device 400 may include: an acquisition unit 401, a detection unit 402, a first determination unit 403, and a second determination unit 404. The main functions of each component unit are as follows:

[0103] The acquisition unit 401 is used to acquire the lower high voltage signal;

[0104] The detection unit 402 is used to respond to the lower high voltage signal and sequentially detect the branch current in M ​​preset cycles within a preset time period, where M is an integer greater than or equal to 1, and the branch current is the current of the branch where the contactor is located, and the contactor includes a main negative contactor and a main positive contactor;

[0105] The first determination unit 403 is used to stop the detection if it is detected that the branch current in the Nth preset cycle is less than or equal to the preset current value, and determine to generate a first contactor disconnection signal according to the detected branch current in the Nth preset cycle, where N is an integer greater than or equal to 1 and less than or equal to M, and the contactor disconnection signal is used to indicate disconnection of the contactor; or

[0106] The second determination unit 404 is used to determine that a circuit breaker disconnection signal is generated first, and then generate a second contactor disconnection signal if it is detected that the branch currents within M preset cycles are all greater than the preset current value. The circuit breaker disconnection signal is used to indicate the disconnection of the circuit breaker, and the second contactor disconnection signal is used to indicate the disconnection of the contactor.

[0107] In a possible implementation, the first contactor disconnection signal includes a first main negative disconnection signal and a first main positive disconnection signal, or a second main positive disconnection signal and a second main negative disconnection signal;

[0108] The first determining unit 403 is specifically configured to:

[0109] If it is detected that the branch current in the Nth preset cycle is less than or equal to the preset current value, the detection is stopped, and the energy storage system is in a charging state. According to the detected branch current in the Nth preset cycle, it is determined to preferentially generate a first main negative disconnection signal, and then generate a first main positive disconnection signal, wherein the first main negative disconnection signal and the first main positive disconnection signal are used to indicate disconnection of the main negative contactor and disconnection of the main positive contactor, respectively;

[0110] or

[0111] If it is detected that the branch current in the Nth preset cycle is less than or equal to the preset current value, the detection is stopped and the energy storage system is in a discharging state. According to the detected branch current in the Nth preset cycle, it is determined to preferentially generate the first main positive disconnect signal and then generate the first main negative disconnect signal. The first main positive disconnect signal and the first main negative disconnect signal are used to indicate the disconnection of the main positive contactor and the disconnection of the main negative contactor, respectively.

[0112] In a possible implementation, the second contactor disconnection signal includes: a third main positive disconnection signal and a third main negative disconnection signal, and the third main positive disconnection signal and the third main negative disconnection signal are used to indicate disconnection of the main positive contactor and the main negative contactor, respectively.

[0113] According to an embodiment of another aspect, an energy storage system is provided. Figure 5 FIG. 1 is a schematic block diagram of the energy storage system according to an embodiment. Figure 5 As shown, the system 500 may include: a lower high voltage device 501 of the energy storage system, a main negative contactor 502, a main positive contactor 503 and a circuit breaker 504. The main functions of each component unit are as follows:

[0114] The lower high-voltage device 501 of the energy storage system can be Figure 4 The lower high-voltage device of the energy storage system is shown.

[0115] The main negative contactor 502 is used to disconnect according to a first contactor disconnection signal from the lower high-voltage device of the energy storage system; or to disconnect according to a second contactor disconnection signal from the lower high-voltage device of the energy storage system.

[0116] The main positive contactor 503 is used to disconnect according to a first contactor disconnection signal from the lower high-voltage device of the energy storage system; or to disconnect according to a second contactor disconnection signal from the lower high-voltage device of the energy storage system.

[0117] The circuit breaker 504 is used to disconnect according to the circuit breaker disconnection signal from the lower high-voltage device of the energy storage system.

[0118] In a possible implementation, the first contactor disconnection signal includes a first main negative disconnection signal and a first main positive disconnection signal, or a second main positive disconnection signal and a second main negative disconnection signal;

[0119] The main negative contactor 502 is specifically used to preferentially disconnect according to the first main negative disconnect signal when the energy storage system is in a charging state;

[0120] The main positive contactor 503 is specifically used to disconnect according to the first main positive disconnection signal after the main negative contactor is disconnected when the energy storage system is in a charging state;

[0121] or

[0122] The main positive contactor 503 is specifically used to preferentially disconnect according to the second main positive disconnect signal when the energy storage system is in a discharging state;

[0123] The main negative contactor 502 is specifically used to disconnect according to the second main negative disconnection signal after the main positive contactor is disconnected when the energy storage system is in a discharging state.

[0124] In a possible implementation, the second contactor disconnection signal includes: a third main positive disconnection signal and a third main negative disconnection signal;

[0125] The circuit breaker 504 is specifically used to preferentially disconnect according to the circuit breaker disconnection signal;

[0126] The main positive contactor 504 is specifically used to disconnect according to the third main positive disconnect signal after the circuit breaker is disconnected;

[0127] The main negative contactor 503 is specifically used to be disconnected according to the third main negative disconnection signal after the circuit breaker is disconnected.

[0128] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment. The device embodiment described above is only schematic, wherein the unit described as a separate component may or may not be physically separated, and the component displayed as a unit may or may not be a physical unit, that is, it may be located in one place, or it may be distributed on multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative work.

[0129] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the embodiments of the present invention, rather than to limit them. Although the embodiments of the present invention have been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for reducing high pressure in an energy storage system, characterized in that: include: Get the lower high voltage signal; In response to the lower high-voltage signal, the branch currents in M ​​preset cycles within a preset time period are detected in sequence, where M is an integer greater than or equal to 1, and the branch current is the current of the branch where the contactor is located, and the contactor includes a main negative contactor and a main positive contactor; If it is detected that the branch current in the Nth preset cycle is less than or equal to the preset current value, the detection is stopped, and according to the detected branch current in the Nth preset cycle, a first contactor disconnection signal is determined to be generated, where N is an integer greater than or equal to 1 and less than or equal to M, and the first contactor disconnection signal is used to indicate disconnection of the contactor; If it is detected that the branch currents within M preset cycles are all greater than the preset current value, it is determined to preferentially generate a circuit breaker disconnection signal, and then generate a second contactor disconnection signal, wherein the circuit breaker disconnection signal is used to indicate disconnection of the circuit breaker, and the second contactor disconnection signal is used to indicate disconnection of the contactor.

2. The method according to claim 1, characterized in that The first contactor disconnect signal includes a first main negative disconnect signal and a first main positive disconnect signal, or a second main positive disconnect signal and a second main negative disconnect signal; If it is detected that the branch current in the Nth preset cycle is less than or equal to the preset current value, the detection is stopped, and according to the detected branch current in the Nth preset cycle, a first contactor disconnection signal is determined to be generated, including: If it is detected that the branch current in the Nth preset cycle is less than or equal to the preset current value, the detection is stopped, and the energy storage system is in a charging state. According to the detected branch current in the Nth preset cycle, it is determined to preferentially generate a first main negative disconnection signal, and then generate a first main positive disconnection signal, wherein the first main negative disconnection signal and the first main positive disconnection signal are used to indicate disconnection of the main negative contactor and disconnection of the main positive contactor, respectively; or If it is detected that the branch current in the Nth preset cycle is less than or equal to the preset current value, the detection is stopped, and according to the detected branch current in the Nth preset cycle, a first contactor disconnection signal is determined to be generated, including: If it is detected that the branch current in the Nth preset cycle is less than or equal to the preset current value, the detection is stopped and the energy storage system is in a discharging state. According to the detected branch current in the Nth preset cycle, it is determined to preferentially generate the first main positive disconnect signal and then generate the first main negative disconnect signal. The first main positive disconnect signal and the first main negative disconnect signal are used to indicate the disconnection of the main positive contactor and the disconnection of the main negative contactor, respectively.

3. The method according to claim 1, characterized in that: The second contactor disconnection signal includes: a third main positive disconnection signal and a third main negative disconnection signal, and the third main positive disconnection signal and the third main negative disconnection signal are used to indicate disconnection of the main positive contactor and the main negative contactor, respectively.

4. The method according to any one of claims 1 to 3, characterized in that: The preset time period is 2s, and the preset period is 100ms.

5. A lower high-voltage device for an energy storage system, characterized in that: include: An acquisition unit, used for acquiring a lower high voltage signal; A detection unit, configured to respond to the lower high voltage signal and sequentially detect branch currents in M ​​preset cycles within a preset time period, where M is an integer greater than or equal to 1, and the branch current is the current of the branch where the contactor is located, and the contactor includes a main negative contactor and a main positive contactor; A first determination unit is used for stopping detection if it is detected that the branch current in the Nth preset cycle is less than or equal to the preset current value, and determining to generate a first contactor disconnection signal according to the detected branch current in the Nth preset cycle, where N is an integer greater than or equal to 1 and less than or equal to M, and the contactor disconnection signal is used to indicate disconnection of the contactor; or The second determination unit is used to determine that a circuit breaker disconnection signal is generated first, and then a second contactor disconnection signal is generated if it is detected that the branch currents within M preset cycles are all greater than a preset current value. The circuit breaker disconnection signal is used to indicate the disconnection of the circuit breaker, and the second contactor disconnection signal is used to indicate the disconnection of the contactor.

6. The device according to claim 5, characterized in that The first contactor disconnect signal includes a first main negative disconnect signal and a first main positive disconnect signal, or a second main positive disconnect signal and a second main negative disconnect signal; The first determining unit is specifically configured to: If it is detected that the branch current in the Nth preset cycle is less than or equal to the preset current value, the detection is stopped, and the energy storage system is in a charging state. According to the detected branch current in the Nth preset cycle, it is determined to preferentially generate a first main negative disconnection signal, and then generate a first main positive disconnection signal, wherein the first main negative disconnection signal and the first main positive disconnection signal are used to indicate disconnection of the main negative contactor and disconnection of the main positive contactor, respectively; or If it is detected that the branch current in the Nth preset cycle is less than or equal to the preset current value, the detection is stopped and the energy storage system is in a discharging state. According to the detected branch current in the Nth preset cycle, it is determined to preferentially generate the first main positive disconnect signal and then generate the first main negative disconnect signal. The first main positive disconnect signal and the first main negative disconnect signal are used to indicate the disconnection of the main positive contactor and the disconnection of the main negative contactor, respectively.

7. The device according to claim 5, characterized in that The second contactor disconnection signal includes: a third main positive disconnection signal and a third main negative disconnection signal, and the third main positive disconnection signal and the third main negative disconnection signal are used to indicate disconnection of the main positive contactor and the main negative contactor, respectively.

8. An energy storage system, characterized in that: include: The lower high-voltage device of the energy storage system is the lower high-voltage device of the energy storage system according to any one of claims 5 to 7; A main negative contactor, used for disconnecting according to a first contactor disconnection signal from a lower high-voltage device of the energy storage system; or disconnected according to a disconnection signal of the second contactor from the lower high-voltage device of the energy storage system; A main positive contactor, used for disconnecting according to a first contactor disconnection signal from a lower high-voltage device of the energy storage system; or disconnected according to a disconnection signal of the second contactor from the lower high-voltage device of the energy storage system; The circuit breaker is used to disconnect according to the circuit breaker disconnection signal from the high-voltage device under the energy storage system.

9. The system according to claim 8, characterized in that The first contactor disconnect signal includes a first main negative disconnect signal and a first main positive disconnect signal, or a second main positive disconnect signal and a second main negative disconnect signal; The main negative contactor is specifically used to preferentially disconnect according to the first main negative disconnect signal when the energy storage system is in a charging state; The main positive contactor is specifically used to disconnect according to the first main positive disconnection signal after the main negative contactor is disconnected when the energy storage system is in a charging state; or The main positive contactor is specifically used to preferentially disconnect according to the second main positive disconnect signal when the energy storage system is in a discharging state; The main negative contactor is specifically used to disconnect according to the second main negative disconnection signal after the main positive contactor is disconnected when the energy storage system is in a discharging state.

10. The system according to claim 8, characterized in that The second contactor disconnect signal includes: a third main positive disconnect signal and a third main negative disconnect signal; The circuit breaker is specifically used to preferentially disconnect according to the circuit breaker disconnection signal; The main positive contactor is specifically used to disconnect according to the third main positive disconnect signal after the circuit breaker is disconnected; The main negative contactor is specifically used to be disconnected according to the third main negative disconnection signal after the circuit breaker is disconnected.

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