Battery management system, energy storage system and battery addressing method

Abstract

The present application relates to the field of power management technology, and specifically to a battery management system, an energy storage system and a battery addressing method. By utilizing the insulation detection unit in the battery management system, the ground wire of the cabinet is connected to the upper and lower bridge arms of the insulation detection balance bridge in the insulation detection unit, so that the ground wire of the cabinet is at the middle potential position of the battery pack voltage, and the ground wire of each sub-control unit is connected to the ground wire of the cabinet. In this way, it is only necessary to connect the ground wire of each sub-control unit to the ground wire of the cabinet to dynamically identify and adjust the address of the battery cell unit. The design structure is simple, does not require a complex wiring structure, reduces the impact of noise interference on system addressing, and improves the flexibility and adaptability of the system.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of power management technology, and specifically to a battery management system, an energy storage system, and a battery addressing method. Background Art

[0002] Battery Management System (BMS) is a key component in modern battery technology. Its role is to ensure that the battery system operates in a safe, efficient and optimal performance state. BMS provides an intelligent management method for batteries through a series of complex control and monitoring mechanisms, thereby significantly improving the battery life and reliability.

[0003] The applicant has found in the research that in the battery management system, when managing the addresses of each battery, the existing addressing methods mostly rely on fixed hardware addresses or static configurations, which may cause addressing conflicts, especially in complex battery pack configurations with multiple series. In addition, as the scale of the battery pack increases, the fixed addressing method will lead to increased signal delay, which in turn affects the response speed and real-time performance of the system. Summary of the invention

[0004] In view of the above problems, the embodiments of the present application provide a battery management system, an energy storage system and a battery addressing method to solve the above technical problems existing in the prior art.

[0005] According to one aspect of an embodiment of the present application, there is provided a battery management system, including: a cabinet, a battery pack, an insulation detection unit and a main control unit;

[0006] The battery pack is arranged in the cabinet and is insulated from the cabinet; the battery pack includes a plurality of battery cells and a plurality of sub-control units, the plurality of battery cells are connected in series, the plurality of sub-control units are respectively connected to the plurality of battery cells for controlling the battery cells, the plurality of sub-control units are electrically connected to the main control unit via a communication bus, and the plurality of sub-control units are grounded via the ground wire of the cabinet;

[0007] The insulation detection unit includes a first switch, a first pull-down resistor, a second switch and a second pull-down resistor, one end of the first pull-down resistor is electrically connected to the positive electrode of the battery pack through the first switch, one end of the second pull-down resistor is electrically connected to the negative electrode of the battery pack through the second switch, and the other end of the first pull-down resistor and the other end of the second pull-down resistor are connected to the ground wire of the cabinet;

[0008] The main control unit is used to send an addressing instruction to each of the sub-control units through the communication bus when the first switch and the second switch are closed, so that each of the sub-control units obtains the voltage difference between the positive pole of the battery cell unit connected to it and the ground wire of the cabinet; the main control unit is also used to receive the voltage difference sent by each of the sub-control units through the communication bus, assign address information to each of the battery cell units according to the voltage difference, and send the address information of the battery cell unit connected to it to each of the sub-control units through the communication bus.

[0009] Preferably, the first switch and the second switch are switch power tubes.

[0010] According to another aspect of the embodiments of the present application, there is provided an energy storage system, comprising the battery management system described in the above embodiments.

[0011] According to a third aspect of an embodiment of the present application, a battery addressing method is provided, which is applied to the battery management system proposed in the above embodiment, and the method includes:

[0012] S1: close the first switch and the second switch;

[0013] S2: Sending an addressing instruction to each sub-control unit so that each sub-control unit obtains a voltage difference between the positive electrode of the battery cell unit connected thereto and the ground wire of the cabinet;

[0014] S3: receiving the voltage difference sent by each sub-control unit;

[0015] S4: allocating address information to each battery cell unit according to the voltage difference;

[0016] S5: Sending address information of the battery cell units connected thereto to each of the sub-control units.

[0017] Preferably, after receiving the voltage difference sent by each of the sub-control units, the method further includes:

[0018] Acquire the number of voltage difference values ​​received and sent by each of the sub-control units;

[0019] Determine, according to the number of the voltage differences and the preset number of battery cell units, whether the number of the voltage differences received within a first preset time is equal to the preset number of battery cell units;

[0020] If the number of the voltage differences is not equal to the preset number of battery cell units, and exceeds the first preset time, the number of errors N is accumulated, where N is a natural number.

[0021] Preferably, the allocating address information to each battery cell unit according to the voltage difference includes:

[0022] Each received voltage difference is verified according to a preset voltage difference threshold value. If the verification succeeds, address information is allocated to each battery cell unit according to the voltage difference value; if the verification fails, the number of errors N is accumulated.

[0023] Preferably, the allocating address information to each battery cell unit according to the voltage difference includes:

[0024] The received voltage difference values ​​are sorted, and addresses are sequentially allocated to the battery cell units corresponding to the voltage difference values ​​according to the sorting.

[0025] Preferably, the sending of address information of the battery cell unit connected to each of the sub-control units includes:

[0026] An address allocation message is broadcasted to each of the sub-control units, wherein the address allocation message includes a voltage difference and address information allocated to the battery cell corresponding to the voltage difference, so that each of the sub-control units determines the address information of the battery cell connected thereto according to the voltage difference.

[0027] Preferably, the method further comprises:

[0028] Determine whether a successful address information allocation message sent by each sub-control unit is received within a second preset time;

[0029] If the address information allocation success message is received, the stored address information of each of the battery cell units is updated, and an address storage message is sent to each of the sub-control units so that each of the sub-control units stores the address information;

[0030] If the address information allocation success message is not received and the second preset time has passed, the number of errors N is accumulated, and the address allocation message continues to be sent to each sub-control unit in a broadcasting manner.

[0031] Preferably, the method further comprises:

[0032] If the number of errors N is greater than a preset error number threshold, an error prompt is issued, the number of errors N is reset to zero, and the updating of the address information of each of the battery cell units is stopped.

[0033] A battery management system, energy storage system and battery addressing method proposed in the embodiment of the present application, by using the insulation detection unit in the battery management system, the ground wire of the cabinet is connected to the upper and lower bridge arms of the insulation detection balance bridge in the insulation detection unit, so that the ground wire of the cabinet is at the middle potential position of the battery pack voltage, and the ground wire of each battery cell unit is connected to the ground wire of the cabinet. When the main control unit is addressing, after the upper and lower bridge arms of the insulation detection balance bridge in the insulation detection unit are turned on, an addressing instruction is sent to each sub-control unit, and each sub-control unit reports the voltage difference between the positive pole of each battery cell unit and the ground wire of the cabinet, and the main control unit performs address allocation according to the voltage difference between the positive pole of each battery cell unit and the ground wire of the cabinet. In this way, it is only necessary to connect the ground wire of each sub-control unit to the ground wire of the cabinet to dynamically identify and adjust the address of the battery cell unit. The design structure is simple, does not require a complex wiring structure, reduces the impact of noise interference on system addressing, and improves the flexibility and adaptability of the system.

[0034] The above description is only an overview of the technical solution of the embodiment of the present application. In order to more clearly understand the technical means of the embodiment 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 embodiment 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

[0035] The accompanying drawings are only used to illustrate the embodiments and are not to be considered as limiting the present application. In addition, the same reference symbols are used to represent the same components throughout the accompanying drawings. In the accompanying drawings:

[0036] Figure 1 A battery addressing communication topology diagram provided in an embodiment of the present application;

[0037] Figure 2 A schematic diagram of the structure of a battery management system provided in an embodiment of the present application;

[0038] Figure 3 A flow chart of a battery addressing method provided in an embodiment of the present application;

[0039] Figure 4 A flow chart of another battery addressing method provided in an embodiment of the present application. DETAILED DESCRIPTION

[0040] The exemplary embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present application are shown in the drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein.

[0041] Battery addressing in the battery management system (BMS) is a key technology that ensures accurate monitoring and management of each battery cell in the battery pack. In the BMS system, the battery pack usually includes multiple battery cells. In the BMS system, the battery cells are often managed as units. Therefore, the BMS system needs to assign addresses to each battery cell of the battery pack. The addressing mechanism in the BMS system allows the BMS to identify and access each battery cell, so that individual voltage and temperature monitoring, state of charge (SOC) and state of health (SOH) estimation, and battery balancing can be performed. With the development of technology, the addressing method of BMS is also constantly improving. For example, automatic addressing is achieved through the CAN bus circuit to improve the accuracy and efficiency of the system. The introduction of these technologies enables BMS to better serve multiple fields such as new energy vehicles, energy storage systems, and power tools, ensuring the stable and safe operation of the battery system in various complex environments.

[0042] The inventor of the present application found in the research that when using the potential method to address the battery cell, by detecting the potential from the negative electrode (B-) of the battery pack to each battery cell in the entire battery management system, it is necessary to arrange a special measurement circuit for each battery cell, and then determine the position of the battery cell in the battery pack by calculating the potential of the battery cell. Since it is necessary to detect the potential from the negative electrode (B-) of the battery pack to each battery cell in the entire battery management system, it is necessary to arrange a special measurement circuit for each battery cell, which will complicate the wiring harness and increase the difficulty and cost of addressing.

[0043] In view of this, the embodiment of the present application proposes a battery management system, an energy storage system and a battery addressing method. By utilizing the insulation detection unit in the battery management system, the ground wire of the cabinet is connected to the upper and lower bridge arms of the insulation detection balance bridge in the insulation detection unit, so that the ground wire of the cabinet is at the middle potential position of the battery pack voltage, and the ground wire of each battery cell unit is connected to the ground wire of the cabinet. When the main control unit is addressed, after the upper and lower bridge arms of the insulation detection balance bridge in the insulation detection unit are turned on, an addressing instruction is sent to each sub-control unit, and each sub-control unit reports the voltage difference between the positive pole of each battery cell unit and the ground wire of the cabinet, and the main control unit performs address allocation according to the voltage difference between the positive pole of each battery cell unit and the ground wire of the cabinet. In this way, it is only necessary to connect the ground wire of each sub-control unit to the ground wire of the cabinet to dynamically identify and adjust the address of the battery cell unit. The design structure is simple, does not require a complex wiring structure, reduces the impact of noise interference on system addressing, and improves the flexibility and adaptability of the system.

[0044] like Figure 1 and Figure 2As shown, a bus topology diagram and a structural schematic diagram of a battery management system proposed in an embodiment of the present application are shown. A battery management system proposed in an embodiment of the present application includes: a cabinet, a battery pack, an insulation detection unit and a main control unit.

[0045] The battery pack is arranged in the cabinet and is insulated from the cabinet; the battery pack includes a plurality of battery cells and a plurality of sub-control units, the plurality of battery cells are connected in series with each other, the plurality of sub-control units are respectively connected to the plurality of battery cells for controlling the battery cells, the plurality of sub-control units are electrically connected to the main control unit via a communication bus, and the plurality of sub-control units are grounded via the ground wire of the cabinet.

[0046] The insulation detection unit includes a first switch, a first pull-down resistor, a second switch and a second pull-down resistor, one end of the first pull-down resistor is electrically connected to the positive electrode of the battery pack through the first switch, one end of the second pull-down resistor is electrically connected to the negative electrode of the battery pack through the second switch, and the other end of the first pull-down resistor and the other end of the second pull-down resistor are connected to the ground wire of the cabinet.

[0047] The main control unit is used to send an addressing instruction to each of the sub-control units through the communication bus when the first switch and the second switch are closed, so that each of the sub-control units obtains the voltage difference between the positive pole of the battery cell unit connected to it and the ground wire of the cabinet; the main control unit is also used to receive the voltage difference sent by each of the sub-control units through the communication bus, assign address information to each of the battery cell units according to the voltage difference, and send the address information of the battery cell unit connected to it to each of the sub-control units through the communication bus.

[0048] In the embodiment of the present application, the cabinet is a physical chassis for placing a battery pack. In the cabinet, a battery pack, an insulation detection circuit board, and a main control board are placed. The battery pack is composed of multiple battery cells. Usually, the battery cells in the battery pack are connected together in series to form the positive and negative electrodes of the battery pack. The positive and negative electrodes of the battery pack are insulated from the cabinet to prevent leakage of the battery pack. The cabinet is provided with a ground wire for connecting to the ground. Each battery cell is provided with a sub-circuit board, and a sub-control unit is provided on the sub-circuit board. The sub-control unit is used to control the battery cell, including configuring address information for the battery cell, obtaining temperature information and status information of the battery cell, and monitoring the fault of the battery cell. The ground wire of each sub-control unit is connected to the ground wire of the cabinet and grounded through the ground wire of the cabinet. In the cabinet, since there are multiple ways to set the ground wire of the cabinet, each sub-control unit can be easily connected to the ground wire of the cabinet in the cabinet without the need for additional complex wiring.

[0049] In order to monitor the status of the battery pack, the main control unit of the battery management system is set on the main control board. Figure 1 The bus topology structure is connected to each sub-control unit. The communication bus can be a CAN bus or other buses. Through the CAN bus, the main control unit can send messages to each sub-control unit in a broadcasting manner, and each sub-control unit can also send messages to the main control unit and other sub-control units in a broadcasting manner.

[0050] In the embodiment of the present application, in order to detect the insulation state of the battery pack, an insulation detection unit is provided, and the insulation detection unit includes an insulation detection balance bridge, such as Figure 2 As shown, the insulation detection balance bridge includes an upper bridge arm and a lower bridge arm, wherein the upper bridge arm includes a first switch SWu and a first pull-down resistor Rsu, and the lower bridge arm includes a second switch SWn and a second pull-down resistor Rsn. One end of the upper bridge arm is mainly connected to the positive voltage of the battery pack, and the other end is connected to the ground wire GND of the cabinet; one end of the lower bridge arm is connected to the negative voltage of the battery pack, and the other end is connected to the ground wire GND of the cabinet. Figure 2 As shown, one end of the first pull-down resistor Rsu is electrically connected to the positive electrode of the battery pack through the first switch SWu, one end of the second pull-down resistor Rsn is electrically connected to the negative electrode of the battery pack through the second switch SWn, and the other end of the first pull-down resistor Rsu and the other end of the second pull-down resistor Rsn are connected to the ground wire GND of the cabinet. When the upper bridge arm and the lower bridge arm are closed, the ground wire of the cabinet is at the middle potential position of the battery pack voltage, for example: assuming that the battery pack voltage is 700V, the potential at the ground wire GND of the cabinet is 350V.

[0051] like Figure 2 As shown, assuming that the battery pack contains 4 battery cells BAT1, BAT2, BAT3 and BAT4, the voltage of each battery cell is 60V, and the battery cells are connected in series, the total voltage of the battery pack is 240V. When the upper bridge arm and the lower bridge arm are turned on, the potential at the ground wire of the cabinet is 120V. Since the ground wire of the sub-control unit connected to the battery cell is connected to the ground wire of the cabinet, the voltage difference between the positive electrode of the battery cell measured by each sub-control unit and the cabinet ground wire is: V1 is -60V, V2 is 0V, V3 is 60V, and V4 is 120V.

[0052] The main control unit is an MCU unit or a DSP unit, etc., which is connected to the sub-control unit through a communication bus on the one hand, and is electrically connected to the first switch SWu and the second switch SWn on the other hand, for controlling the first switch SWu and the second switch SWn. The first switch SWu and the second switch SWn can be two switch power tubes, respectively, and their gates are connected to the main control unit respectively. The main control unit controls the switch power tube by sending a high level or a low level to realize the on and off of the upper bridge arm and the lower bridge arm.

[0053] When it is necessary to assign an address to each battery cell, such as when the system is restarted, the main control unit controls the first switch SWu and the second switch SWn to be closed, and can send an addressing instruction to each sub-control unit in a broadcast manner through the communication bus. After each sub-control unit receives the addressing instruction sent by the main control unit, the sub-control unit obtains the voltage difference between the positive electrode of the battery cell connected to it and the ground wire of the cabinet, such as Figure 2 As shown, the voltage difference V4 obtained by the sub-control unit connected to BAT4 is 120 V, the voltage difference obtained by the sub-control unit connected to BAT3 is 60 V, the voltage difference obtained by the sub-control unit connected to BAT2 is 0 V, and the voltage difference of the sub-control unit connected to BAT1 is -60 V. The sub-control unit reports the obtained voltage difference of the battery cell unit connected to it to the main control unit.

[0054] After receiving the voltage difference of the battery cell units sent by each sub-control unit, the main control unit analyzes the voltage difference, identifies different battery cell units, and then allocates address information to each battery cell unit according to the voltage difference value, for example, sorting the voltage differences by size, such as Figure 2 As shown, the address information assigned to BAT1 is 1, the address information assigned to BAT2 is 2, the address information assigned to BAT3 is 3, and the address information assigned to BAT4 is 4. Of course, the main control unit can also assign address information to each battery cell unit in other ways, which is not limited in the present invention.

[0055] When the main control unit completes address allocation to each battery cell unit, it will send the address information of the battery cell unit connected to it to each sub-control unit through the communication bus. In order to enable each sub-control unit to recognize the address information allocated to itself by the main control unit, the main control unit can associate the address information with the received voltage difference when sending the address allocation message. Each sub-control unit can recognize the address information allocated to itself through the voltage difference.

[0056] After each sub-control unit recognizes the address information allocated by the main control unit to itself, it writes the address information into its own storage system. In the subsequent communication process, the sub-control unit will use the address information to communicate with each control unit.

[0057] The embodiment of the present application adopts the above method, and the circuit structure is simple, and no modification is required to the circuit in the cabinet. It is only necessary to connect the ground wire of the sub-control unit to the ground wire of the cabinet, and control the insulation detection unit through the main control unit to realize the addressing operation of each battery cell. When each battery cell changes, for example, when the battery cell is damaged or the number of battery cells changes, the sub-control unit can obtain the voltage difference between the positive electrode of the battery cell and the cabinet ground wire in real time. Compared with the traditional potential measurement method, it is not necessary to obtain the potential difference of each battery cell relative to the negative electrode of the battery pack, and there is no need to lay a special measurement circuit. The design structure is simple, which reduces the impact of noise interference on system addressing and improves the flexibility and adaptability of the system.

[0058] Based on the battery management system proposed in the above embodiment, the present application embodiment also proposes a battery addressing method, specifically as follows Figure 3 As shown, a flow chart of the battery addressing method is shown. The method is applied to the battery management system proposed in the above embodiment and is executed by the main control unit.

[0059] Step S1: closing the first switch and the second switch;

[0060] Depend on Figure 2 As can be seen from the above embodiments, the first switch and the second switch are electrically connected to the main control unit respectively, and the main control unit controls the on and off of the insulation detection balance bridge by controlling the first switch and the second switch. When the battery management system is started, an address needs to be assigned first. At this time, the main control unit sends a control signal to the first switch and the second switch to make them in a conducting state, so that the ground wire of the cabinet is at the middle potential of the battery pack.

[0061] It should be pointed out that, under normal circumstances, the first switch and the second switch are both in the open state. The first switch and the second switch need to be turned on only when insulation detection or addressing is required. After addressing is completed, the main control unit can disconnect the first switch and the second switch again.

[0062] Step S2: sending an addressing instruction to each sub-control unit so that each sub-control unit obtains a voltage difference between the positive electrode of the battery cell unit connected thereto and the ground wire of the cabinet;

[0063] The main control unit sends an addressing instruction to each sub-control unit in a broadcasting manner through the control bus, so that each sub-control unit automatically detects the voltage difference between the positive electrode of the battery cell unit connected thereto and the ground wire of the cabinet after receiving the addressing instruction. It can be seen from the above embodiment that the ground wire of the sub-control unit is connected to the ground wire of the cabinet, so the sub-control unit can very conveniently obtain the voltage difference between the positive electrode of the battery cell unit and the ground wire of the cabinet.

[0064] Step S3: receiving the voltage difference sent by each sub-control unit;

[0065] When the sub-control unit obtains the voltage difference between the positive electrode of the battery cell unit connected to it and the ground wire of the cabinet, the voltage difference is reported to the main control unit, wherein each sub-control unit reports the voltage difference in a broadcasting manner. The main control unit receives the voltage difference reported by each sub-control unit through the bus.

[0066] Step S4: assigning address information to each battery cell unit according to the voltage difference;

[0067] After the main control unit receives the voltage difference reported by all the sub-control units in the battery management system, the voltage difference is analyzed, and address information is assigned to each battery cell unit according to preset rules. The preset rules can be implemented in a variety of ways, such as: assigning in sequence, or assigning according to the time of receipt, etc. We do not limit this here.

[0068] Step S5: sending address information of the battery cell units connected thereto to each of the sub-control units.

[0069] When the main control unit completes the address allocation to each sub-control unit, it broadcasts the address information to each sub-control unit through the communication bus in a broadcasting manner. In order to enable each sub-control unit to identify the address information allocated to it by the main control unit, the main control unit can send the voltage difference value to the sub-control unit in the broadcast message by associating the address information with the voltage difference value. After receiving the voltage difference value and the associated address information, the sub-control unit confirms whether the voltage difference value is the voltage difference between the positive electrode of the connected battery cell unit and the cabinet ground wire. If so, the address information is stored and used as its own address for subsequent battery management.

[0070] The battery addressing method proposed in the embodiment of the present application is applied to the battery management system proposed in the above embodiment. The voltage difference between the positive electrode of the battery cell unit reported by each sub-control unit and the ground wire of the cabinet is obtained, and the voltage difference is analyzed. Address information is allocated to each battery cell unit according to the voltage difference. The operation is simple, and address information can be allocated to the battery cell unit in real time. At the same time, the influence of noise interference on system addressing is reduced, and the flexibility and adaptability of the system are improved.

[0071] Figure 4 A battery addressing method proposed in another embodiment of the present application is shown, comprising the following steps:

[0072] Step S101: closing the first switch and the second switch;

[0073] Step S102: sending an addressing instruction to each sub-control unit;

[0074] Step S103: receiving the voltage difference sent by each sub-control unit;

[0075] When the battery management system is started or initialized, the main control unit needs to start the addressing operation. Steps S101-S103 are the same as steps S1-S3, and will not be repeated here.

[0076] Step S104: acquiring the number of voltage difference values ​​received and sent by each of the sub-control units;

[0077] After receiving the voltage difference value sent by the sub-control unit, the main control unit needs to confirm whether the voltage difference value information sent by all sub-control units has been received to prevent battery management problems caused by missing battery cells. In an embodiment of the present application, the main control unit can determine whether the voltage difference values ​​sent by all sub-control units have been received by counting the number of voltage difference values ​​sent by the sub-control units.

[0078] Step S105: determining whether the number of voltage differences is equal to the number of preset battery cell units;

[0079] In a battery management system, the number of battery cells included in a battery pack is usually preset so that the battery management system can effectively manage all the battery cells. The preset number of battery cells is usually stored by a main control unit.

[0080] After obtaining the number of voltage difference values ​​reported by the sub-control units, the number of reported voltage difference values ​​is compared with the number of pre-set battery cell units. If the two are equal, it means that all sub-control units have reported voltage difference values, and the battery management system works normally, and then go to step S108. If the two are not equal, usually, the number of reported voltage difference values ​​is less than the number of pre-set battery cell units, and then go to step S106.

[0081] Step S106: Determine whether the first timer has timed out;

[0082] When the main control unit determines the number of voltage difference values ​​reported by the sub-control unit, sometimes the two numbers are different because the voltage difference value reported by the sub-control unit has not yet been received. In the embodiment of the present application, in order to provide system robustness, the time for the main control unit to receive the voltage difference value reported by the sub-control unit is limited. After the main control unit sends the addressing instruction, the first timer is started, and the timing duration of the first timer is a first preset time. If the timing duration has not expired, go to step 101, and the main control unit restarts the addressing operation; if the timing duration expires, go to step S107.

[0083] Step S107: Determine whether the number of errors N is greater than a preset error number threshold;

[0084] In order to improve the fault tolerance of the battery management system, in the embodiment of the present application, when the first timer times out, the number of timer timeouts is also counted. Initially, the number of errors N is 0. When the timer times out once, that is, an error occurs once, N is increased by 1. If the number of errors N is greater than the preset error number threshold, it means that a serious error has occurred in the battery management system, and it is necessary to stop the addressing operation and go to step S115. If the number of errors N is not greater than the preset error number threshold, it means that the battery management system can continue to work, then go to step S101 and re-perform the addressing operation. Preferably, the preset error number threshold is 5.

[0085] Step S108: Verify whether it is successful;

[0086] In order to further improve the robustness of the battery management system, in an embodiment of the present application, when the main control unit receives the voltage difference reported by the sub-control unit, the received voltage difference is first verified to determine the accuracy of the voltage difference.

[0087] The main control unit compares the received voltage differences according to the preset voltage difference threshold. If they are within the preset voltage difference threshold range, for example, when the voltage of each battery cell is 60V, the voltage difference threshold range is 60±5V. If they are within this range, it means that there is no problem with the reported voltage difference. The verification is successful, and the process goes to step S109. Address information is assigned to each battery cell according to the voltage difference. If the verification fails, that is, the voltage difference reported by each sub-control unit is not within the voltage difference threshold range, it means that there is an error in the voltage difference reported by the sub-control unit. The verification fails, then the number of errors N is accumulated by 1, and the process goes to step S107.

[0088] Step S109: sorting the received voltage difference values, and assigning addresses to the battery cell units corresponding to the voltage difference values ​​in sequence according to the sorting;

[0089] After the main control unit receives the voltage difference values ​​reported by all the sub-control units and all the voltage difference values ​​pass the verification, the main control unit assigns address information to each battery cell according to the voltage difference value corresponding to each battery cell. Preferably, in the embodiment of the present application, the main control unit sorts the voltage difference values ​​and assigns addresses to the battery cells corresponding to each voltage difference in turn according to the sorting, for example Figure 2 In the example, the voltage differences of the positive electrodes of the battery cells measured by each sub-control unit relative to the cabinet ground wire are respectively -60V for V1, 0V for V2, 60V for V3, and 120V for V4. Then, the address information assigned to BAT1 is 1, the address information assigned to BAT2 is 2, the address information assigned to BAT3 is 3, and the address information assigned to BAT4 is 4. This allocation method is simple and practical, and can greatly improve the efficiency of address allocation.

[0090] Step S110: sending an address allocation message to each of the sub-control units in a broadcasting manner;

[0091] An address allocation message is broadcasted to each of the sub-control units, wherein the address allocation message includes a voltage difference and address information allocated to the battery cell corresponding to the voltage difference, so that each of the sub-control units determines the address information of the battery cell connected thereto according to the voltage difference.

[0092] Step S111: determining whether an address information allocation success message sent by each sub-control unit is received;

[0093] After each sub-control unit receives the address information sent by the main control unit, each sub-control unit needs to send an address information allocation success message to the main control unit to notify the main control unit that the address information has been successfully received, so that the information stored on both the main control unit and the sub-control unit is consistent.

[0094] When the main control unit successfully receives the address information allocation success message, it means that the address allocation is successful, and the process goes to step S112.

[0095] When the main control unit does not receive the address information allocation success message sent by the sub-control unit, the process goes to step S113.

[0096] Step S112: updating the stored address information of each of the battery cell units, and sending an address storage message to each of the sub-control units so that each of the sub-control units stores the address message;

[0097] The address information of each battery cell unit is updated and stored on the main control unit side, and each sub-control unit is notified to store the address message through the address storage message to maintain the consistency of the information stored in the main control unit and the sub-control unit. In the subsequent control process, the newly allocated address information will be used for interaction.

[0098] Step S113: Determine whether the second timer has timed out;

[0099] In order to improve the robustness of the battery management system, after the main control unit sends an address allocation message to each sub-control unit, the main control unit starts a second timer to control the time for receiving the sub-control unit to send an address information allocation success message, and the timing duration of the second timer is a second preset time.

[0100] When the second timer has not timed out, it is possible that the address information allocation success message has not been received due to system delay, and the process continues to wait for the address allocation success message sent by the sub-control unit; when the second timer has timed out, the process goes to step S114.

[0101] Step S114: determining whether the number of errors N is greater than a preset error number threshold;

[0102] In order to improve the fault tolerance of the battery management system, in an embodiment of the present application, when the second timer times out, the number of timer timeouts will also be counted. In the initial state, the number of errors N is 0. When the timer times out once, that is, an error occurs once, N is increased by 1. If the number of errors N is greater than the preset error number threshold, it means that a serious error has occurred in the battery management system, and it is necessary to stop the addressing operation and go to step S115. If the number of errors N is not greater than the preset error number threshold, it means that the battery management system can continue to work, and then continue to wait for the address allocation success message sent by the sub-control unit. Preferably, the preset error number threshold is 5.

[0103] It should be pointed out that the number of errors in this step and the number of errors in step S107 can be accumulated at the same time or separately. If accumulated at the same time, the reliability of the system can be improved; if accumulated separately, the robustness of the system can be improved. The battery management system can be set autonomously as needed, which is not limited in the embodiments of the present application.

[0104] Step S115: issuing an error prompt, clearing the number of errors N, and stopping updating the address information of each battery cell unit;

[0105] When the number of errors N exceeds the preset error threshold, it means that a serious error has occurred in the battery management system. At this time, the main control unit stops updating the address information of each battery cell unit, clears the number of errors N, and continues to use the address information before the update to control the battery cell unit in order to solve the problem in the system.

[0106] The embodiments of the present application further propose an energy storage system, which includes a battery management system proposed in any of the above embodiments. The working methods of the battery management system have been described in the above embodiments and will not be repeated here.

[0107] In summary, a battery management system, energy storage system and battery addressing method proposed in the embodiment of the present application, by utilizing the insulation detection unit in the battery management system, connects the ground wire of the cabinet to the upper and lower bridge arms of the insulation detection balance bridge in the insulation detection unit, so that the ground wire of the cabinet is at the middle potential position of the battery pack voltage, and connects the ground wire of each battery cell unit to the ground wire of the cabinet. When the main control unit is addressing, after the upper and lower bridge arms of the insulation detection balance bridge in the insulation detection unit are turned on, an addressing instruction is sent to each sub-control unit, and each sub-control unit reports the voltage difference between the positive pole of each battery cell unit and the ground wire of the cabinet, and the main control unit performs address allocation according to the voltage difference between the positive pole of each battery cell unit and the ground wire of the cabinet. In this way, it is only necessary to connect the ground wire of each sub-control unit to the ground wire of the cabinet to dynamically identify and adjust the address of the battery cell unit. The design structure is simple, does not require a complex wiring structure, reduces the impact of noise interference on system addressing, and improves the flexibility and adaptability of the system.

[0108] The algorithm or display provided here are not inherently related to any specific computer, virtual system or other equipment. Various general systems can also be used together with the teaching based on this. According to the above description, it is obvious to construct the structure required for this type of system. In addition, the present application embodiment is not directed to any specific programming language yet. It should be understood that various programming languages ​​can be utilized to realize the content of the present application described here, and the above description of specific languages ​​is to disclose the best mode of implementation of the present application.

[0109] In the description provided herein, a large number of specific details are described. However, it is understood that the embodiments of the present application can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0110] Similarly, it should be understood that in order to streamline the present application and help understand one or more of the various aspects of the invention, in the above description of exemplary embodiments of the present application, the various features of the embodiments of the present application are sometimes grouped together into a single embodiment, figure, or description thereof.

[0111] Those skilled in the art will appreciate that the modules in the devices in the embodiments may be adaptively changed and arranged in one or more devices different from the embodiments. The modules or units or components in the embodiments may be combined into one module or unit or component, and may be divided into a plurality of submodules or subunits or subcomponents. Except that at least some of such features and / or processes or units are mutually exclusive, all features disclosed in this specification (including the accompanying abstract and drawings) and all processes or units of any method or device disclosed in this manner may be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying abstract and drawings) may be replaced by an alternative feature providing the same, equivalent or similar purpose.

[0112] It should be noted that the above embodiments illustrate the present application rather than limit the present application, and those skilled in the art may design alternative embodiments without departing from the scope. The steps in the above embodiments, unless otherwise specified, should not be understood as limiting the execution order.

Claims

1. A battery management system, characterized in that: include: Cabinets, battery packs, insulation detection units and main control units; The battery pack is arranged in the cabinet and is insulated from the cabinet; the battery pack includes a plurality of battery cells and a plurality of sub-control units, the plurality of battery cells are connected in series, the plurality of sub-control units are respectively connected to the plurality of battery cells for controlling the battery cells, the plurality of sub-control units are electrically connected to the main control unit via a communication bus, and the plurality of sub-control units are grounded via the ground wire of the cabinet; The insulation detection unit includes a first switch, a first pull-down resistor, a second switch and a second pull-down resistor, one end of the first pull-down resistor is electrically connected to the positive electrode of the battery pack through the first switch, one end of the second pull-down resistor is electrically connected to the negative electrode of the battery pack through the second switch, the other end of the first pull-down resistor and the other end of the second pull-down resistor are connected to the ground wire of the cabinet, and when the first switch and the second switch are closed, the ground wire of the cabinet is at the middle potential position of the battery pack voltage; The main control unit is used to send an addressing instruction to each of the sub-control units through the communication bus when the first switch and the second switch are closed, so that each of the sub-control units obtains the voltage difference between the positive pole of the battery cell unit connected to it and the ground wire of the cabinet; the main control unit is also used to receive the voltage difference sent by each of the sub-control units through the communication bus, assign address information to each of the battery cell units according to the voltage difference, and send the address information of the battery cell unit connected to it to each of the sub-control units through the communication bus.

2. The battery management system according to claim 1, characterized in that: The first switch and the second switch are switch power tubes.

3. An energy storage system, characterized in that: Comprising a battery management system as claimed in claim 1 or 2.

4. A battery addressing method, characterized in that: Applied to the battery management system according to claim 1 or 2, the method comprises: S1: close the first switch and the second switch; S2: Sending an addressing instruction to each sub-control unit so that each sub-control unit obtains a voltage difference between the positive electrode of the battery cell unit connected thereto and the ground wire of the cabinet; S3: receiving the voltage difference sent by each sub-control unit; S4: allocating address information to each battery cell unit according to the voltage difference; S5: Sending address information of the battery cell units connected thereto to each of the sub-control units.

5. The battery addressing method according to claim 4, characterized in that: After receiving the voltage difference sent by each of the sub-control units, the method further includes: Acquire the number of voltage difference values ​​received and sent by each of the sub-control units; Determine, according to the number of the voltage differences and the preset number of battery cell units, whether the number of the voltage differences received within a first preset time is equal to the preset number of battery cell units; If the number of the voltage differences is not equal to the preset number of battery cell units, and exceeds the first preset time, the number of errors N is accumulated, where N is a natural number.

6. The battery addressing method according to claim 5, characterized in that: The allocating address information to each battery cell unit according to the voltage difference includes: Each received voltage difference is verified according to a preset voltage difference threshold value. If the verification succeeds, address information is allocated to each battery cell unit according to the voltage difference value; if the verification fails, the number of errors N is accumulated.

7. The battery addressing method according to claim 6, characterized in that: The allocating address information to each battery cell unit according to the voltage difference includes: The received voltage difference values ​​are sorted, and addresses are sequentially allocated to the battery cell units corresponding to the voltage difference values ​​according to the sorting.

8. The battery addressing method according to claim 7, characterized in that: The sending the address information of the battery cell unit connected to each of the sub-control units comprises: An address allocation message is broadcasted to each of the sub-control units, wherein the address allocation message includes a voltage difference and address information allocated to the battery cell corresponding to the voltage difference, so that each of the sub-control units determines the address information of the battery cell connected thereto according to the voltage difference.

9. The battery addressing method according to claim 8, characterized in that: The method further comprises: Determine whether a successful address information allocation message sent by each sub-control unit is received within a second preset time; If the address information allocation success message is received, the stored address information of each of the battery cell units is updated, and an address storage message is sent to each of the sub-control units so that each of the sub-control units stores the address information; If the address information allocation success message is not received and the second preset time has passed, the number of errors N is accumulated, and the address allocation message continues to be sent to each sub-control unit in a broadcasting manner.

10. The battery addressing method according to claim 5, 6 or 9, characterized in that: The method further comprises: If the number of errors N is greater than a preset error number threshold, an error prompt is issued, the number of errors N is reset to zero, and the updating of the address information of each battery cell unit is stopped.

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