Power consumption balancing circuit and cascaded battery management system

Abstract

The utility model discloses a power consumption balancing circuit and a cascade battery management system, the power consumption balancing circuit comprises a power consumption control sub-circuit, a power consumption sub-circuit and a current limiting circuit, the first end of the power consumption control sub-circuit is electrically connected with the first end of the current limiting circuit; the second end of the power consumption control sub-circuit is electrically connected with the first end of the power consumption sub-circuit, the third end of the power consumption control sub-circuit is electrically connected with a slave front-end chip, the second end of the power consumption sub-circuit is grounded, and the second end of the current limiting circuit is electrically connected with a main battery cell group; wherein the slave front-end chip is electrically connected with the slave battery cell group, and the power consumption balancing circuit is used for consuming a voltage difference when the voltage difference exists between the master battery cell group and the slave battery cell group so as to balance the power consumption between the master battery cell group and the slave battery cell group. Therefore, according to the utility model, the voltage difference between the main battery cell group and the slave battery cell group can be consumed through the power consumption balancing circuit, the power consumption between the main battery cell group and the slave battery cell group is balanced, and the utilization efficiency of the battery cells is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and in particular to a power consumption balancing circuit and a cascade battery management system. Background Art

[0002] At present, in multi-string battery management systems, multiple chips are often cascaded to implement the system architecture. However, when related modules in the system (such as isolation modules) draw power from a certain chip, a voltage difference will occur between battery cells connected to different chips, reducing the utilization efficiency of the battery cells.

[0003] It can be seen that how to balance the power consumption among battery cells and improve the utilization efficiency of battery cells is particularly important. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a power consumption balancing circuit and a cascade battery management system, which can balance the power consumption between battery cells and improve the utilization efficiency of the battery cells.

[0005] In order to solve the above technical problems, the utility model discloses a power consumption balancing circuit in the first aspect, which is applied to a cascade battery management system, the cascade battery management system includes a slave front-end chip, the cascade battery management system is used to manage a master cell group and a slave cell group, and the power consumption balancing circuit includes a power consumption control subcircuit, a power consumption subcircuit and a current limiting circuit, wherein:

[0006] The first end of the power consumption control subcircuit is electrically connected to the first end of the current limiting circuit, the second end of the power consumption control subcircuit is electrically connected to the first end of the power consumption subcircuit, the third end of the power consumption control subcircuit is used to electrically connect to the slave front-end chip, the second end of the power consumption subcircuit is used to ground, and the second end of the current limiting circuit is used to electrically connect to the main battery cell group;

[0007] Among them, the slave front-end chip is electrically connected to the slave battery group, and the power consumption balancing circuit is used to consume the voltage difference when there is a voltage difference between the master battery group and the slave battery group to balance the power consumption between the master battery group and the slave battery group.

[0008] As an optional implementation, in the first aspect of the utility model, the power consumption control subcircuit includes a power consumption control transistor, wherein:

[0009] The collector of the power consumption control transistor is electrically connected to the first end of the current limiting circuit, the emitter of the power consumption control transistor is electrically connected to the first end of the power consumption sub-circuit, and the base of the power consumption control transistor is used to electrically connect to the slave front-end chip.

[0010] As an optional implementation, in the first aspect of the utility model, the power consumption subcircuit includes a potentiometer, wherein:

[0011] The first end of the potentiometer is electrically connected to the emitter of the power consumption control transistor, and the second end of the potentiometer is used for grounding.

[0012] As an optional implementation, in the first aspect of the utility model, the current limiting circuit includes a resistance module, wherein:

[0013] The first end of the resistance module is electrically connected to the collector of the power consumption control transistor, the second end of the resistance module is used to electrically connect to the main battery cell group, and the resistance module includes at least one current limiting resistor.

[0014] The second aspect of the utility model discloses a cascade battery management system disclosed in the first aspect of the utility model, comprising a power consumption balancing circuit and a slave front-end chip as disclosed in the first aspect of the utility model, and further comprising a master front-end chip, a control module and an isolation module, wherein the cascade battery management system is used to manage a master cell group and a slave cell group, wherein:

[0015] The first end of the main front-end chip is used to electrically connect the main battery cell group, the second end of the main front-end chip is electrically connected to the first end of the control module, the first end of the slave front-end chip is used to electrically connect the slave battery cell group, the second end of the slave front-end chip is electrically connected to the first end of the isolation module, the third end of the slave front-end chip is electrically connected to the first end of the power consumption balancing circuit, the second end of the isolation module is electrically connected to the second end of the control module, and the second end of the power consumption balancing circuit is used to electrically connect the main battery cell group;

[0016] The power consumption balancing circuit is used for consuming the voltage difference when there is a voltage difference between the master battery cell group and the slave battery cell group, so as to balance the power consumption between the master battery cell group and the slave battery cell group.

[0017] As an optional implementation, in the second aspect of the utility model, the slave front-end chip includes a power supply module, the power supply module includes a power isolation unit and a voltage transformation unit, the voltage transformation unit includes a transformer, a first diode, a second diode, a first capacitor and a first resistor, wherein:

[0018] The voltage input end of the transformer is used to access the first voltage from the front-end chip and is electrically connected to the first end of the power isolation unit, the first output end of the transformer is electrically connected to the positive electrode of the first diode, the second output end of the transformer is electrically connected to the positive electrode of the second diode, and after the negative electrode of the first diode is electrically connected to the negative electrode of the second diode, they are respectively electrically connected to the first end of the first capacitor, the first end of the first resistor and the first end of the isolation module, and the grounding end of the transformer, the second end of the first capacitor and the second end of the first resistor are respectively used for grounding;

[0019] The voltage transformation unit is used to transform the first voltage into a second voltage and provide the second voltage to the isolation module.

[0020] As an optional implementation, in the second aspect of the present utility model, the power isolation unit includes a power isolation chip and a second capacitor, wherein:

[0021] The voltage input end of the power isolation chip is electrically connected to the voltage input end of the transformer and the first end of the second capacitor respectively, the first transformer drive output end of the power isolation chip is electrically connected to the first drive input end of the transformer, the second transformer drive output end of the power isolation chip is electrically connected to the second drive input end of the transformer, and the ground end of the power isolation chip, the operating frequency selection end of the power isolation chip and the second end of the second capacitor are used for grounding.

[0022] As an optional implementation, in the second aspect of the utility model, the isolation module includes an isolation chip, a second resistor, a third resistor, a fourth resistor and a fifth resistor, wherein:

[0023] The first serial data transmission end of the isolation chip is electrically connected to the first end of the second resistor, the first serial clock transmission end of the isolation chip is electrically connected to the first end of the third resistor, the voltage input end of the isolation chip, the second end of the second resistor and the second end of the third resistor are respectively electrically connected to the voltage output end of the transformer unit, the second serial data transmission end of the isolation chip is electrically connected to the first end of the fourth resistor, the second serial clock transmission end of the isolation chip is electrically connected to the first end of the fifth resistor, and the second end of the fourth resistor and the second end of the fifth resistor are respectively electrically connected to the second end of the control module.

[0024] As an optional implementation, in the second aspect of the present utility model, the main battery cell group includes at least one main battery cell, and the slave battery cell group includes at least one slave battery cell.

[0025] As an optional implementation, in the second aspect of the utility model, the control module includes a single-chip microcomputer, and the isolation module communicates with the control module using an IIC bus protocol.

[0026] The implementation of this utility model has the following beneficial effects:

[0027] The utility model provides a power consumption balancing circuit, which includes a power consumption control subcircuit, a power consumption subcircuit and a current limiting circuit, wherein: the first end of the power consumption control subcircuit is electrically connected to the first end of the current limiting circuit, the second end of the power consumption control subcircuit is electrically connected to the first end of the power consumption subcircuit, the third end of the power consumption control subcircuit is used to electrically connect to the slave front-end chip, the second end of the power consumption subcircuit is used to ground, and the second end of the current limiting circuit is used to electrically connect to the main battery cell group; wherein the slave front-end chip is electrically connected to the slave battery cell group, and the power consumption balancing circuit is used to consume the voltage difference when there is a voltage difference between the main battery cell group and the slave battery cell group, so as to balance the power consumption between the main battery cell group and the slave battery cell group. It can be seen that the utility model can consume the voltage difference between the main battery cell group and the slave battery cell group through the power consumption balancing circuit when there is a voltage difference between the main battery cell group and the slave front-end chip, balance the power consumption between the main battery cell group and the slave battery cell group, and improve the utilization efficiency of the battery cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0029] Figure 1 It is a structural schematic diagram of a power consumption balancing circuit disclosed in an embodiment of the utility model;

[0030] Figure 2 It is a structural schematic diagram of another power consumption balancing circuit disclosed in an embodiment of the utility model;

[0031] Figure 3 It is a structural schematic diagram of a power consumption sub-circuit disclosed in an embodiment of the utility model;

[0032] Figure 4 It is a structural schematic diagram of a cascade battery management system disclosed in an embodiment of the utility model;

[0033] Figure 5 It is a structural schematic diagram of another cascade battery management system disclosed in an embodiment of the utility model;

[0034] Figure 6It is a structural schematic diagram of a power supply module disclosed in an embodiment of the utility model;

[0035] Figure 7 It is a structural schematic diagram of an isolation module disclosed in an embodiment of the utility model. DETAILED DESCRIPTION

[0036] For better understanding and implementation, the technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. 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.

[0037] It should be noted that, unless otherwise clearly specified and limited, the term "electrical connection" in the specification and claims of the utility model and the above-mentioned drawings should be understood in a broad sense. For example, it can be a fixed electrical connection, a detachable electrical connection, or an integral electrical connection; it can be a mechanical electrical connection, an electrical electrical connection, or can communicate with each other; it can be directly connected, or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. In addition, the terms "first", "second", etc. in the specification and claims of the utility model and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. The terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For those of ordinary skill in the art, the specific meanings of the above terms in the utility model can be understood according to specific circumstances.

[0038] The utility model discloses a power consumption balancing circuit and a cascade battery management system, which can balance the power consumption between a main battery cell group and a slave battery cell group, and improve the utilization efficiency of the battery cells. Detailed descriptions are given below.

[0039] Embodiment 1

[0040] See also Figure 1 , Figure 1 This is a schematic diagram of a power consumption balancing circuit disclosed in an embodiment of the utility model. Figure 1 The power consumption balancing circuit shown can be applied to a cascade battery management system, which includes a slave front-end chip. The cascade battery management system is used to manage the master battery group and the slave battery group, which is not limited in the embodiment of the utility model. Figure 1 As shown, the power consumption balancing circuit may include:

[0041] The power consumption control sub-circuit 101, the power consumption sub-circuit 102 and the current limiting circuit 103, wherein:

[0042] The first end of the power consumption control subcircuit 101 is electrically connected to the first end of the current limiting circuit 103, the second end of the power consumption control subcircuit 101 is electrically connected to the first end of the power consumption subcircuit 102, the third end of the power consumption control subcircuit 101 is used to electrically connect to the slave front-end chip, the second end of the power consumption subcircuit 102 is used to ground, and the second end of the current limiting circuit 103 is used to electrically connect to the main battery cell group;

[0043] Among them, the slave front-end chip is electrically connected to the slave battery group, and the power consumption balancing circuit is used to consume the voltage difference when there is a voltage difference between the master battery group and the slave battery group to balance the power consumption between the master battery group and the slave battery group.

[0044] Optionally, when the device in the cascade battery management system draws power from the front-end chip, the voltage of the main battery group will be higher than the voltage of the slave battery group, resulting in a voltage difference between the main battery group and the slave battery group. The power consumption balancing circuit can be used to consume the voltage difference on the main battery group that is higher than the slave battery group, and balance the power consumption between the main battery group and the slave battery group. This is not limited to the embodiments of the utility model.

[0045] It can be seen that the implementation Figure 1 The power consumption balancing circuit described can consume the voltage difference between the main battery cell group and the slave battery cell group through the power consumption balancing circuit when there is a voltage difference between the main battery cell group and the slave front-end chip, balance the power consumption between the main battery cell group and the slave battery cell group, and improve the utilization efficiency of the battery cells.

[0046] In an optional embodiment, if Figure 2 As shown, the power consumption control subcircuit 101 includes a power consumption control transistor Q, wherein:

[0047] The collector of the power control transistor Q is electrically connected to the first end of the current limiting circuit 103, the emitter of the power control transistor Q is electrically connected to the first end of the power consumption sub-circuit 102, and the base of the power control transistor Q is used to electrically connect to the front-end chip.

[0048] Optionally, the voltage input from the front-end chip turns on the power consumption control transistor Q. At this time, the power consumption sub-circuit 102 will divide the voltage of the main battery group to make the voltage of the main battery group equal to the voltage of the slave battery group. This embodiment of the utility model is not limited.

[0049] It can be seen that this optional embodiment can control the operation of the power consumption balancing circuit through the power consumption control transistor, thereby improving the operation stability and reliability of the power consumption balancing circuit.

[0050] In another optional embodiment, Figure 2 As shown, the power consumption subcircuit 102 includes a potentiometer RW, wherein:

[0051] A first end of the potentiometer RW is electrically connected to the emitter of the power consumption control transistor Q, and a second end of the potentiometer RW is used for grounding.

[0052] Optional, such as Figure 2 As shown, the power consumption subcircuit 102 includes a potentiometer RW. At this time, the resistance value of the potentiometer RW can be adjusted to adapt to different power consumption requirements. Further, as an example, Figure 3 As shown, the power consumption sub-circuit 102 can also be composed of at least two resistors in parallel, and the resistance value of each parallel resistor can be determined according to the target resistance value corresponding to the power consumption requirement. The power consumption sub-circuit 102 can also be composed of at least two resistors in parallel, and each resistor corresponds to a resistance switch. The resistance value of each resistor can be the same or different. The resistance of the resistance switch that needs to be closed can be determined according to the target resistance value corresponding to the power consumption requirement, and the embodiment of the utility model is not limited thereto.

[0053] It can be seen that this optional embodiment can consume the voltage difference between the main battery group and the slave battery group through the potentiometer, and can adjust the resistance of the potentiometer to adapt to the consumption of different voltage differences, thereby improving the practicality and convenience of the power consumption balancing circuit.

[0054] In yet another optional embodiment, Figure 2 As shown, the current limiting circuit 103 includes a resistor module 1031, wherein:

[0055] The first end of the resistance module 1031 is electrically connected to the collector of the power consumption control transistor Q, and the second end of the resistance module 1031 is used to be electrically connected to the main battery cell group. The resistance module 1031 includes at least one current limiting resistor.

[0056] Optionally, the resistor module 1031 may include a current-limiting resistor, or may include a resistor group consisting of at least two current-limiting resistors connected in series or in parallel, which is not limited in the embodiment of the utility model.

[0057] Optionally, the power consumption balancing circuit is used to suppress the voltage of the battery cells in the main battery cell group from being higher than the voltage of the battery cells in the slave battery cell group. The working principle of the power consumption balancing circuit may include: the power supply module in the slave front-end chip is used to power the isolation module and is also used to access the power consumption balancing circuit. As long as the isolation module is working, the power consumption balancing circuit works, that is, the power consumption control transistor Q is turned on. At this time, the potentiometer RW will divide the voltage of the main battery cell group, so that the voltage of the main battery cell group is equal to the voltage of the slave battery cell group. The theoretical calculation process is as follows:

[0058] For example, the cells in the master cell group and the slave cell group are lithium iron phosphate batteries. The nominal voltage of each string of lithium iron phosphate batteries is 3.2V, and the circuit current of the detection isolation module is 10mA. The power consumption of the power supply module is:

[0059] P = 3.2V*10mA*a, where a represents the number of battery strings in the battery pack;

[0060] The current from the collector to the emitter of the power control transistor Q in the power balance circuit is:

[0061] I = P / (3.2V*b), where b represents the number of battery strings in the main battery pack;

[0062] Considering the balanced loss of 2mA current in the power balancing circuit, the total resistance in the power balancing circuit is:

[0063] Rtotal = (3.2V*b) / (I-2mA)

[0064] Assuming that the resistance of the resistor module 1031 is 1 kΩ, the resistance of the potentiometer RW is:

[0065] RW=Rtotal-1kΩ

[0066] That is, the resistance of the potentiometer RW needs to be adjusted to Rtotal-1kΩ to consume the voltage difference between the main battery group voltage and the slave battery group voltage. It should be noted that the above data is only for demonstrating the calculation process of the resistance of the potentiometer RW, and the specific data involved is not limited in the embodiment of the utility model.

[0067] Embodiment 2

[0068] See also Figure 4 , Figure 4 This is a schematic diagram of the structure of a cascade battery management system disclosed in an embodiment of the utility model. Figure 4 The cascade battery management system shown includes the power consumption balancing circuit 10 and the slave front-end chip 20 disclosed in the first embodiment. It should be noted that for the detailed description of the power consumption balancing circuit, please refer to the specific description of the relevant content in the first embodiment, which will not be repeated in this embodiment.

[0069] like Figure 4 As shown, the cascade battery management system may also include:

[0070] The main front-end chip 30, the control module 40 and the isolation module 50, the cascade battery management system is used to manage the main battery group 60 and the slave battery group 70, wherein:

[0071] The first end of the main front-end chip 30 is used to electrically connect to the main battery group 60, the second end of the main front-end chip 30 is electrically connected to the first end of the control module 40, the first end of the slave front-end chip 20 is used to electrically connect to the slave battery group 70, the second end of the slave front-end chip 20 is electrically connected to the first end of the isolation module 50, the third end of the slave front-end chip 20 is electrically connected to the first end of the power consumption balance circuit 10, the second end of the isolation module 50 is electrically connected to the second end of the control module 40, and the second end of the power consumption balance circuit 10 is used to electrically connect to the main battery group 60;

[0072] The power consumption balancing circuit 10 is used to consume the voltage difference when there is a voltage difference between the master battery group 60 and the slave battery group 70 , so as to balance the power consumption between the master battery group 60 and the slave battery group 70 .

[0073] Optionally, the main front-end chip 30 and the slave front-end chip 20 can be chips of the same model or chips of different models. Specifically, the main front-end chip 30 and the slave front-end chip 20 can be SH367309 type chips, which is not limited in the embodiments of the present utility model.

[0074] Optional, such as Figure 5 As shown, the main battery cell group 60 may include at least one main battery cell, the slave battery cell group 70 may include at least one slave battery cell, and the number of main battery cells in the main battery cell group 60 may be the same as the number of slave battery cells in the slave battery cell group, in which case m is equal to n, and the number of main battery cells in the main battery cell group 60 may also be different from the number of slave battery cells in the slave battery cell group, in which case m is not equal to n, which is not limited in the embodiments of the present utility model.

[0075] Optionally, the control module 40 may include a single-chip microcomputer, and the control module 40 shares a ground with the main front-end chip 30, but does not share a ground with the slave front-end chip 20. Therefore, an isolation module 50 is set between the control module 40 and the slave front-end chip 20, and the control module 40 and the isolation module 50 can communicate using the IIC bus protocol, the control module 40 and the main front-end chip 30 can communicate using the IIC bus protocol, and the isolation module 50 and the slave front-end chip 20 can communicate using the IIC bus protocol, that is, the control module 40 can implement bus control of the slave front-end chip 20 through the isolation module 50, and the power consumption balancing circuit 10 is used to consume the voltage difference when there is a voltage difference between the main battery cell group 60 and the slave battery cell group 70, so as to balance the power consumption between the main battery cell group 60 and the slave battery cell group 70, which is not limited to the embodiments of the utility model.

[0076] It can be seen that the implementation Figure 4The described cascade battery management system can realize the cascade of at least two front-end chips, support the control of multiple strings of battery cells, improve the compatibility of the system, increase the applicable scenarios of the system, consume the voltage difference between the main battery cell group and the slave battery cell group through the power consumption balancing circuit, balance the power consumption between the main battery cell group and the slave battery cell group, and improve the utilization efficiency of the battery cells.

[0077] In an optional embodiment, if Figure 5 As shown, the front-end chip 20 includes a power supply module 201, such as Figure 6 As shown, the power supply module 201 includes a power isolation unit 2011 and a transformer unit 2012, and the transformer unit 2012 includes a transformer U1, a first diode D1, a second diode D2, a first capacitor C1 and a first resistor R1, wherein:

[0078] The voltage input end of the transformer U1 is used to receive the first voltage from the front-end chip 20 and is electrically connected to the first end of the power isolation unit 2011. The first output end of the transformer U1 is electrically connected to the positive electrode of the first diode D1, and the second output end of the transformer U1 is electrically connected to the positive electrode of the second diode D2. After the negative electrode of the first diode D1 is electrically connected to the negative electrode of the second diode D2, they are respectively electrically connected to the first end of the first capacitor C1, the first end of the first resistor R1 and the first end of the isolation module 50. The ground end of the transformer U1, the second end of the first capacitor C1 and the second end of the first resistor R1 are respectively used for grounding;

[0079] The voltage transformation unit 2012 is used to transform the first voltage into a second voltage and provide the second voltage to the isolation module 50 .

[0080] Optionally, the voltage input end of the transformer U1 is used to connect a first voltage from the front-end chip 20. The first voltage may be a 5V voltage. After the first voltage is transformed by the transformer unit 2012, a second voltage is obtained. The transformer unit 2012 provides the second voltage to the isolation module 50. The second voltage may be a 3.3V voltage, which is not limited in the embodiment of the utility model.

[0081] Optionally, the transformer U1 may include a VPT85BA-01A chip, which is not limited in the embodiment of the present utility model.

[0082] It can be seen that this optional embodiment can transform the first voltage connected to the front-end chip into a second voltage through the transformer unit, and provide the second voltage to the isolation module to power the isolation module, thereby improving the power supply stability and reliability of the isolation module.

[0083] In another optional embodiment, Figure 6 As shown, the power isolation unit 2011 includes a power isolation chip U2 and a second capacitor C2, wherein:

[0084] The voltage input end of the power isolation chip U2 is electrically connected to the voltage input end of the transformer U1 and the first end of the second capacitor C2 respectively, the first transformer drive output end of the power isolation chip U2 is electrically connected to the first drive input end of the transformer U1, the second transformer drive output end of the power isolation chip U2 is electrically connected to the second drive input end of the transformer U1, and the ground end of the power isolation chip U2, the operating frequency selection end of the power isolation chip U2 and the second end of the second capacitor C2 are used for grounding.

[0085] Optionally, the power isolation chip U2 may include a VPS8504B chip, which is not limited in the embodiment of the present utility model.

[0086] It can be seen that this optional embodiment can improve the operating stability of the power supply module through the power isolation unit, thereby improving the power supply stability and reliability of the isolation module.

[0087] In yet another optional embodiment, Figure 7 As shown, the isolation module 50 includes an isolation chip U3, a second resistor R2, a third resistor R3, a fourth resistor R4 and a fifth resistor R5, wherein:

[0088] The first serial data transmission end of the isolation chip U3 is electrically connected to the first end of the second resistor R2, the first serial clock transmission end of the isolation chip U3 is electrically connected to the first end of the third resistor R3, the voltage input end of the isolation chip U3, the second end of the second resistor R2 and the second end of the third resistor R3 are respectively electrically connected to the voltage output end of the transformer unit 2012, the second serial data transmission end of the isolation chip U3 is electrically connected to the first end of the fourth resistor R4, the second serial clock transmission end of the isolation chip U3 is electrically connected to the first end of the fifth resistor R5, and the second end of the fourth resistor R4 and the second end of the fifth resistor R5 are respectively electrically connected to the second end of the control module 40.

[0089] Optionally, the isolation module 50 receives a second voltage, such as a 3.3V voltage, from the voltage output terminal of the transformer unit 2012 to power the isolation module 50. The isolation module 50 communicates with the control module via the IIC bus protocol through the serial data transmission terminal and the serial clock transmission terminal. The isolation chip U3 may include a π220N31 chip, which is not limited in the embodiments of the utility model.

[0090] It can be seen that this optional embodiment can draw power from the front-end chip, thereby improving the convenience of implementing the isolation module. The control module and the front-end chip are isolated through the isolation module, and the control module controls the bus protocol of the front-end chip through the isolation module, thereby improving the control accuracy and reliability of the cascade battery management system.

[0091] The above is a detailed introduction to a power consumption balancing circuit and a cascade battery management system disclosed in an embodiment of the utility model. Specific embodiments are used in this article to illustrate the principles and implementation methods of the utility model, but the above preferred embodiments are not used to limit the utility model. The description of the above embodiments is only used to help understand the method of the utility model and its core idea; at the same time, for general technical personnel in this field, based on the idea of ​​the utility model, without departing from the spirit and scope of the utility model, there will be changes in the specific implementation methods and application scopes. Therefore, the scope of protection of the utility model shall be based on the scope defined by the claims.

Claims

1. A power consumption balancing circuit, characterized in that: The power consumption balancing circuit is applied to a cascade battery management system, the cascade battery management system includes a slave front-end chip, the cascade battery management system is used to manage a master cell group and a slave cell group, the power consumption balancing circuit includes a power consumption control subcircuit, a power consumption subcircuit and a current limiting circuit, wherein: The first end of the power consumption control subcircuit is electrically connected to the first end of the current limiting circuit, the second end of the power consumption control subcircuit is electrically connected to the first end of the power consumption subcircuit, the third end of the power consumption control subcircuit is used to electrically connect to the slave front-end chip, the second end of the power consumption subcircuit is used to ground, and the second end of the current limiting circuit is used to electrically connect to the main battery cell group; Among them, the slave front-end chip is electrically connected to the slave battery group, and the power consumption balancing circuit is used to consume the voltage difference when there is a voltage difference between the master battery group and the slave battery group to balance the power consumption between the master battery group and the slave battery group.

2. The power consumption balancing circuit according to claim 1, characterized in that: The power consumption control subcircuit includes a power consumption control transistor, wherein: The collector of the power consumption control transistor is electrically connected to the first end of the current limiting circuit, the emitter of the power consumption control transistor is electrically connected to the first end of the power consumption sub-circuit, and the base of the power consumption control transistor is used to electrically connect to the slave front-end chip.

3. The power consumption balancing circuit according to claim 2, characterized in that: The power consumption subcircuit includes a potentiometer, wherein: The first end of the potentiometer is electrically connected to the emitter of the power consumption control transistor, and the second end of the potentiometer is used for grounding.

4. The power consumption balancing circuit according to claim 3, characterized in that: The current limiting circuit includes a resistor module, wherein: The first end of the resistance module is electrically connected to the collector of the power consumption control transistor, the second end of the resistance module is used to electrically connect to the main battery cell group, and the resistance module includes at least one current limiting resistor.

5. A cascade battery management system, characterized in that: The cascade battery management system comprises the power consumption balancing circuit and the slave front-end chip according to any one of claims 1 to 4, and also comprises a master front-end chip, a control module and an isolation module, wherein the cascade battery management system is used to manage the master cell group and the slave cell group, wherein: The first end of the main front-end chip is used to electrically connect the main battery cell group, the second end of the main front-end chip is electrically connected to the first end of the control module, the first end of the slave front-end chip is used to electrically connect the slave battery cell group, the second end of the slave front-end chip is electrically connected to the first end of the isolation module, the third end of the slave front-end chip is electrically connected to the first end of the power consumption balancing circuit, the second end of the isolation module is electrically connected to the second end of the control module, and the second end of the power consumption balancing circuit is used to electrically connect the main battery cell group; The power consumption balancing circuit is used for consuming the voltage difference when there is a voltage difference between the master battery cell group and the slave battery cell group, so as to balance the power consumption between the master battery cell group and the slave battery cell group.

6. The cascade battery management system according to claim 5, characterized in that: The slave front-end chip includes a power supply module, the power supply module includes a power isolation unit and a voltage transformation unit, the voltage transformation unit includes a transformer, a first diode, a second diode, a first capacitor and a first resistor, wherein: The voltage input end of the transformer is used to access the first voltage from the front-end chip and is electrically connected to the first end of the power isolation unit, the first output end of the transformer is electrically connected to the positive electrode of the first diode, the second output end of the transformer is electrically connected to the positive electrode of the second diode, and after the negative electrode of the first diode is electrically connected to the negative electrode of the second diode, they are respectively electrically connected to the first end of the first capacitor, the first end of the first resistor and the first end of the isolation module, and the grounding end of the transformer, the second end of the first capacitor and the second end of the first resistor are respectively used for grounding; The voltage transformation unit is used to transform the first voltage into a second voltage and provide the second voltage to the isolation module.

7. The cascade battery management system according to claim 6, characterized in that: The power isolation unit includes a power isolation chip and a second capacitor, wherein: The voltage input end of the power isolation chip is electrically connected to the voltage input end of the transformer and the first end of the second capacitor respectively, the first transformer drive output end of the power isolation chip is electrically connected to the first drive input end of the transformer, the second transformer drive output end of the power isolation chip is electrically connected to the second drive input end of the transformer, and the ground end of the power isolation chip, the operating frequency selection end of the power isolation chip and the second end of the second capacitor are used for grounding.

8. The cascade battery management system according to claim 6 or 7, characterized in that: The isolation module includes an isolation chip, a second resistor, a third resistor, a fourth resistor and a fifth resistor, wherein: The first serial data transmission end of the isolation chip is electrically connected to the first end of the second resistor, the first serial clock transmission end of the isolation chip is electrically connected to the first end of the third resistor, the voltage input end of the isolation chip, the second end of the second resistor and the second end of the third resistor are respectively electrically connected to the voltage output end of the transformer unit, the second serial data transmission end of the isolation chip is electrically connected to the first end of the fourth resistor, the second serial clock transmission end of the isolation chip is electrically connected to the first end of the fifth resistor, and the second end of the fourth resistor and the second end of the fifth resistor are respectively electrically connected to the second end of the control module.

9. The cascade battery management system according to claim 7, characterized in that: The main battery cell group includes at least one main battery cell, and the slave battery cell group includes at least one slave battery cell.

10. The cascade battery management system according to any one of claims 5 to 7, characterized in that: The control module includes a single chip microcomputer, and the isolation module communicates with the control module using an IIC bus protocol.

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