Battery cluster balancing system

Abstract

The present disclosure discloses a balancing system for a battery cluster, the battery cluster includes a plurality of battery modules, and any two adjacent battery modules are connected in series, and the balancing system includes a switch module, a transitional energy storage module and a control module, the switch module is connected to each battery module, the transitional energy storage module is connected to the switch module, and the control module is used to control the on and / or off of the switch of the switch module, so that the transitional energy storage module balances multiple consecutive target battery modules through the turned-on switch of the switch module.

Description

[Technical Field]

[0001] FIELD OF THE DISCLOSURE The present disclosure relates to the field of energy technology, and more particularly to a balancing system for battery clusters. [Background technology]

[0002] Currently, with the increase in installed capacity of new energy sources, energy storage has gradually become an important supporting technology for building new power systems. Battery energy storage has been widely used due to its advantages of fast response, short construction period, and small site area. Battery clusters in battery systems are often composed of multiple cells connected in series. Voltage and energy imbalances are likely to occur between the series-connected cells, affecting the available capacity of the battery cluster. However, balancing systems in related technologies have problems such as slow balancing speed. Summary of the Invention

[0003] An embodiment of a first aspect of the present disclosure proposes a balancing system for a battery cluster, the battery cluster including a plurality of battery modules, and any two adjacent battery modules are connected in series; the balancing system includes a switch module, a transitional energy storage module, and a control module, the switch module is connected to each of the battery modules, the transitional energy storage module is connected to the switch module, and the control module is used to control the on and / or off of the switches of the switch module, so that the transitional energy storage module balances a plurality of consecutive target battery modules through the on-switches of the switch module.

[0004] In one embodiment of the present disclosure, the switch module includes a switch transistor unit, a switch unit, a third switch, and an inductor, the switch transistor unit, the switch unit, and the battery module have a one-to-one correspondence, any two adjacent switch transistor units are connected in series, each switch transistor unit includes a first switch transistor and a second switch transistor, a first end of the first switch transistor is connected to a positive electrode of a corresponding battery module, a second end of the first switch transistor is connected to a first end of the second switch transistor, and a second end of the second switch transistor is connected to a negative electrode of a corresponding battery module; Each of the switch units includes a first switch and a second switch, a first end of each of the first switches connected to the second end of the inductor, a second end of each of the first switches connected to the second end of a first switch transistor of a corresponding switch transistor unit, a first end of each of the second switches connected to a negative electrode of the transitional energy storage module, and a second end of each of the second switches connected to the second end of a second switch transistor of a corresponding switch transistor unit; The transitional energy storage module includes a plurality of transitional energy storage batteries, and any two adjacent transitional energy storage batteries are connected in series; The third switches correspond one-to-one to the transitional energy storage batteries, and a first end of each of the third switches is connected to a positive electrode of the corresponding transitional energy storage battery, and a second end of each of the third switches is connected to a first end of the inductor.

[0005] In one embodiment of the present disclosure, the battery cluster includes m battery modules, and the m battery modules are consecutively numbered from 1 to m, the negative electrode of the battery module numbered 1 is the negative electrode of the battery cluster, the positive electrode of the battery module numbered m is the positive electrode of the battery cluster, and the target battery module includes battery modules numbered p to q, where 1≦p≦q≦m; The control module is further used to control a target first switch of a first switch unit and a target second switch of a second switch unit to be on, control the remaining first switches except for the target first switch to be off, and control the remaining second switches except for the target second switch to be off, wherein the first switch unit is a switch unit corresponding to a battery module numbered q, and the second switch unit is a switch unit corresponding to a battery module numbered p.

[0006] In one embodiment of the present disclosure, in each operating cycle of the switch transistors, the switch transistors include the first switch transistor and the second switch transistor, and the control module is further used for: controlling a target second switch transistor of a target switch transistor unit to be on for a first predetermined length of time; controlling a target first switch transistor of the target switch transistor unit to be off while controlling the target second switch transistor to be on; after controlling the target second switch transistor to be on for the first predetermined length of time, controlling the target first switch transistor to be on for a second predetermined length of time; controlling the target second switch transistor to be off while controlling the target first switch transistor to be on; and controlling the switch transistors of the remaining switch transistor units other than the target switch transistor unit to remain off during the operating cycle, wherein the target switch transistor unit is a switch transistor unit corresponding to a battery module numbered q.

[0007] In one embodiment of the present disclosure, the control module is further adapted to adjust a duty cycle of the target second switch transistor to adjust a balanced current flowing through the inductor.

[0008] In one embodiment of the present disclosure, the control module is further used to determine a target value of the balancing current based on the remaining capacity (remaining capacity) of each of the target battery modules, and to determine a target value of the duty cycle based on the target value of the balancing current.

[0009] In one embodiment of the present disclosure, the control module includes a regulator, which is used to adjust the target value of the duty cycle according to the target value of the balancing current and the current value of the balancing current.

[0010] In one embodiment of the present disclosure, the transitional energy storage module includes j transitional energy storage batteries, and the j transitional energy storage batteries are consecutively numbered from No. 1 to No. j, the negative electrode of the transitional energy storage battery No. 1 is the negative electrode of the transitional energy storage module, and the positive electrode of the transitional energy storage battery No. k is the positive electrode of the transitional energy storage module, and the target transitional energy storage batteries include transitional energy storage batteries No. 1 to No. k, and the target transitional energy storage battery is a transitional energy storage battery for balancing the target battery module, where 1≦k≦j; The control module is further used for determining a number k according to the voltage of each of the target battery modules and the range of values ​​of the duty cycle, and controlling the third switch corresponding to the transitional energy storage battery numbered k to be on, and controlling the third switches corresponding to the remaining transitional energy storage batteries excluding the transitional energy storage battery numbered k to be off.

[0011] In one embodiment of the present disclosure, the control module is further used to obtain an average value of the remaining capacities of a plurality of consecutive battery module candidates in response to the variance value between the remaining capacities of each of the battery modules being greater than a predetermined threshold, and to set the plurality of battery module candidates corresponding to the maximum average value as first target battery modules whose balance category is discharging, and set the plurality of battery module candidates corresponding to the minimum average value as second target battery modules whose balance category is charging. [Effects of the Invention]

[0012] Additional aspects and advantages of the present disclosure will be set forth in part in the description that follows, and in part will be obvious from the description, or may be learned by practice of the present disclosure. [Brief explanation of the drawings]

[0013] The above and / or additional aspects and advantages of the present disclosure will become apparent and be readily understood from the following description of the embodiments taken in conjunction with the drawings. [Figure 1] 1 is a structural schematic diagram of a battery cluster balancing system according to an embodiment of the present disclosure; [Figure 2] FIG. 1 is a structural schematic diagram of a battery cluster balancing system according to another embodiment of the present disclosure. [Figure 3] FIG. 1 is a structural schematic diagram of a battery cluster balancing system according to another embodiment of the present disclosure. [Figure 4] 4 is a schematic diagram of the on / off signals of the target first switch transistor Sqa and the target second switch transistor Sqb, and the balancing current iL in the battery cluster balancing system shown in FIG. 3. FIG. [Figure 5] FIG. 4 is an equivalent circuit diagram of the balancing system of the battery cluster shown in FIG. 3 in mode 1. [Figure 6] FIG. 4 is an equivalent circuit diagram of the balancing system of the battery cluster shown in FIG. 3 in mode 2. [Figure 7] FIG. 1 is a structural schematic diagram of a battery cluster balancing system according to another embodiment of the present disclosure. [Figure 8] 8 is a schematic diagram of the on / off signals of the target first switch transistor S4a and the target second switch transistor S4b, and the balancing current iL in the battery cluster balancing system shown in FIG. 7. FIG. [Figure 9] 8 is an equivalent circuit diagram of the battery cluster balancing system shown in FIG. 7 when balancing battery modules 3 in mode 1. FIG. [Figure 10] 8 is an equivalent circuit diagram of the battery cluster balancing system shown in FIG. 7 when balancing battery modules 3 and 4 in mode 2. FIG. [Figure 11] 8 is a schematic diagram of the on / off signals of the target first switch transistor S2a and the target second switch transistor S2b, and the balancing current iL in the battery cluster balancing system shown in FIG. 7; FIG. [Figure 12] 8 is an equivalent circuit diagram of the battery cluster balancing system shown in FIG. 7 when balancing battery modules 1 in mode 1. FIG. [Figure 13] 8 is an equivalent circuit diagram of the battery cluster balancing system shown in FIG. 7 when balancing battery modules 1 and 2 in mode 2. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0014]

[0030] The following detailed description of the embodiments of the present disclosure is provided below. Examples of the above-described embodiments are shown in the drawings, in which the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. It should be understood that the embodiments described below with reference to the drawings are merely examples for explaining the present disclosure, and are not intended to limit the present disclosure.

[0015] The battery cluster balancing system according to the embodiment of the present disclosure will be described below in conjunction with the drawings.

[0016] The battery cluster includes multiple battery modules, and any two adjacent battery modules are connected in series. For example, the battery module includes multiple cells, and any two adjacent cells are connected in series. The number of battery modules and cells is not particularly limited. For example, the battery cluster includes m battery modules, and each battery module includes n cells, where m and n are both positive integers. The type of cell is not particularly limited. For example, the cell includes, but is not limited to, a lithium iron phosphate battery, a ternary polymer lithium battery, etc.

[0017] In one embodiment, as shown in FIG. 2 , battery cluster 200 includes m battery modules, each designated battery module 1 to battery module m, where any two adjacent battery modules are connected in series, and m battery modules are consecutively numbered from number 1 to number m, with the negative electrode of battery module number 1 (corresponding to battery module 1 in FIG. 2 ) being the negative electrode of battery cluster 200, and the positive electrode of battery module number m (corresponding to battery module m in FIG. 2 ) being the positive electrode of battery cluster 200.

[0018] FIG. 1 is a structural schematic diagram of a battery cluster balancing system according to one embodiment of the present disclosure.

[0019] 1, a battery cluster balancing system 100 according to an embodiment of the present disclosure includes a switch module 101, a transitional energy storage module 102, and a control module 103. The switch module 101 is connected to each battery module, the transitional energy storage module 102 is connected to the switch module 101, and the control module 103 is used to control the on and / or off of the switch of the switch module 101, so that the transitional energy storage module 102 balances multiple consecutive target battery modules through the turned-on switches of the switch module 101. As can be seen, the target battery modules are connected in series.

[0020] In addition, the transitional energy storage module 102 is used to store and / or discharge electrical energy. When the balance category is discharging, the transitional energy storage module 102 is used to store the electrical energy discharged by each target battery module. When the balance category is charging, the transitional energy storage module 102 is used to discharge electrical energy and charge each target battery module.

[0021] 3, the battery cluster 200 includes m battery modules, numbered 1 to m, and the target battery modules include battery modules numbered p to q, i.e., the target battery modules include battery modules p to q, and the number of target battery modules is q-p+1, where p and q are both positive integers and 1≦p≦q≦m.

[0022] In one embodiment, the number of target battery modules is equal to or less than half of the total number of battery modules. Continuing with FIG. 3 as an example, the target battery modules include battery modules numbered p to q, where p and q are the battery modules that satisfy the condition: Meets JPEG0007770563000001.jpg35161.

[0023] In one embodiment, the control module 103 further calculates the average remaining capacity of a plurality of consecutive battery module candidates in response to a variance value between the remaining capacity (SOC: State of Charge) of each battery module being greater than a predetermined threshold (indicating an imbalance in the remaining capacity of the battery modules). The plurality of battery module candidates corresponding to the largest average capacity are designated as first target battery modules with a balancing category of discharge, and the plurality of battery module candidates corresponding to the smallest average capacity are designated as second target battery modules with a balancing category of charge. However, the predetermined threshold, the number of first target battery modules, and the number of second target battery modules are not particularly limited. For example, the number of first target battery modules and the number of second target battery modules may be the same or different. This allows the system to determine the target battery modules required for equalization (balancing) based on the remaining capacity of the battery modules, thereby avoiding the impact of performance differences between different batteries on the equalization (balancing) effect.

[0024] In one embodiment, the number of the first target battery modules and the number of the second target battery modules are each equal to or less than half of the total number of battery modules.

[0025] In one embodiment, there are no overlapping battery modules between the first target battery module and the second target battery module.

[0026] In one embodiment, the control module 103 further obtains an average value of the remaining capacities of a first number of consecutive battery module candidates in response to the variance value between the remaining capacities of each battery module being greater than a predetermined threshold, and sets the first number of battery module candidates corresponding to the maximum average value as a first target battery module whose balancing category is discharging, and sets the first number of battery module candidates corresponding to the minimum average value as a second target battery module whose balancing category is charging; when it recognizes that there are a second number of overlapping battery modules between the first target battery module and the second target battery module, it updates the first number based on the second number, and returns to the step of obtaining the average value of the remaining capacities of the first number of consecutive battery module candidates and subsequent steps until there are no overlapping battery modules between the first target battery module and the second target battery module.

[0027] In one embodiment, the battery cluster includes m battery modules, and the first number is the largest integer less than m / 2.

[0028] In one embodiment, updating the first number based on the second number may include setting the difference between the first number and the second number as the updated first number.

[0029] In one embodiment, the transitional energy storage module 102 is used to store the electrical energy discharged by each first target battery module until the average remaining capacity of all first target battery modules is equal to the average remaining capacity of all battery modules in the battery cluster.

[0030] The transitional energy storage module 102 is further used to discharge electrical energy to charge each second target battery module until the average remaining capacity of all second target battery modules is equal to the average remaining capacity of all battery modules in the battery cluster.

[0031] In summary, the battery cluster balancing system of the embodiment of the present disclosure allows the control module to control the on / off of the switches of the switch module, so that the transitional energy storage module can balance multiple consecutive target battery modules through the on switches of the switch module, thereby achieving balancing of multiple consecutive battery modules simultaneously, and greatly improving the balancing speed of the battery cluster.

[0032] According to any of the above embodiments, the switch module 101 includes a switch transistor unit, a switch unit, and an inductor. The switch transistor unit, the switch unit, and the battery module have a one-to-one correspondence. Any two adjacent switch transistor units are connected in series.

[0033] Continuing with the example of FIG. 2, the switch module 101 includes m switch transistor units, m switch units, and one inductor L.

[0034] Each switch transistor unit includes a first switch transistor S xa and the second switch transistor S xb and a first switch transistor S xa The first end of the first switch transistor S is connected to the positive electrode of the corresponding battery module. xa The second end of the second switch transistor S xb and a second switch transistor S xb The second end of each of the S is connected to the negative electrode of the corresponding battery module, where x is a positive integer and 1≦x≦m. However, as shown in FIG. 1a ~S ma is S xaand S 1b ~S mb is S xb For example, S 1a The first end of the S is connected to the positive electrode of the battery module 1, 1a The second end of S 1b connected to the first end of S 1b The second end of S is connected to the negative electrode of the battery module 1, 2a ~S ma The connection format is S 1a You can refer to S 2b ~S mb The connection format is S 1b , and detailed description thereof will be omitted here. However, the type of the switch transistor is not particularly limited. For example, the switch transistor may include a metal-oxide-semiconductor field-effect transistor (MOSFET), in which case the first terminal of the switch transistor may be a drain electrode, and the second terminal of the switch transistor may be a source electrode.

[0035] Each switch unit is a first switch K xa and second switch K xb each first switch K xa The first end of the first switch K is connected to the second end of the inductor L. xa The second end of the first switch transistor S xa and each second switch K xb The first end of the second switch K is connected to the negative terminal of the transitional energy storage module 102. xb The second end of the second switch transistor S xb However, as shown in Figure 2, 1a ~K ma is K xa and K 1b ~K mb is K xb For example, K 1a ~K ma The first end of is connected to the second end of the inductor L, and K1a The second end of S 1a connected to the second end of K 1b ~K mb a first end of the K connected to the negative electrode of the transitional energy storage module 102; 1b The second end of S 1b connected to the second end of K 2a ~K ma The connection format is K 1a You can refer to K 2b ~K mb The connection format is K 1b , and a detailed description thereof will be omitted here.

[0036] In one embodiment, the transitional energy storage module 102 includes multiple transitional energy storage batteries, and any two adjacent transitional energy storage batteries are connected in series. The switch module 101 further includes third switches, each corresponding to a transitional energy storage battery, with a first end of the third switch connected to the positive electrode of the corresponding transitional energy storage battery, and a second end of the third switch connected to a first end of the inductor.

[0037] 2, the transitional energy storage module 102 includes j transitional energy storage batteries, each of which is designated as A1 to A j The j transitional energy storage batteries are consecutively numbered from 1 to j, and the negative electrode of the transitional energy storage battery numbered 1 (corresponding to the transitional energy storage battery A1 in FIG. 2) is the negative electrode of the transitional energy storage module 102, and the negative electrode of the transitional energy storage battery numbered k (corresponding to the transitional energy storage battery A1 in FIG. 2) is the negative electrode of the transitional energy storage module 102. k The positive electrode of the transitional energy storage module 102 corresponds to the positive electrode of the transitional energy storage module 102, and the target transitional energy storage battery includes transitional energy storage batteries numbered 1 to k, that is, the target transitional energy storage battery includes transitional energy storage battery A1 to transitional energy storage battery A2. kThe target transitional energy storage battery is a transitional energy storage battery for balancing the target battery module, where k and j are both positive integers, and 1≦k≦j.

[0038] Continuing with the example of FIG. 2, the switch module 101 includes j third switches, each of which is designated by K t1 ~K tj The third switch corresponds one-to-one with the transitional energy storage battery, and the third switch K ty The first end of the corresponding transitional energy storage battery A y and each third switch K ty The second end of the inductor K is connected to the first end of the inductor L, where y is a positive integer and 1≦y≦j. However, as shown in FIG. t1 ~K tj is K ty and A1~A j is A y For example, K t1 The first terminal of the transitional energy storage battery A1 is connected to the positive electrode of the transitional energy storage battery A1, and the first terminal of the transitional energy storage battery A1 is connected to the positive electrode of the transitional energy storage battery A1. t1 ~K tj The second end of is connected to the first end of the inductor L, and K t2 ~K tj The connection format is K t1 , and a detailed description thereof will be omitted here.

[0039] This allows the system to include only one inductor, significantly reducing the number of inductors and capacitors, reducing the complexity and volume of the balancing system.

[0040] In one embodiment, still referring to FIG. 3 as an example, the target battery modules include battery modules numbered p to q, i.e., the target battery modules include battery module p to battery module q. The control module 103 further controls the target first switch K qa , the target second switch K of the second switch unit pb Turn on the target first switch K qa The remaining first switches except for the target second switch K are controlled to be off.pb The first switch unit is a switch unit corresponding to the battery module numbered q (corresponding to battery module q in FIG. 3), and the second switch unit is a switch unit corresponding to the battery module numbered p (corresponding to battery module p in FIG. 3). Thus, the control module controls the target first switch and the target second switch to be on and controls the remaining first switches and the remaining second switches to be off, so that the transitional energy storage module can balance the battery modules numbered p to number q via the target first switch and the target second switch.

[0041] In one embodiment, still referring to FIG. 3, in each operating cycle of the switch transistor, the first switch transistor S xa and the second switch transistor S xb However, as shown in Figure 3, S 1a ~S ma is S xa and S 1b ~S mb is S xb The control module 103 further controls the target second switch transistor S qb is controlled to be on for a first predetermined length of time, and a target second switch transistor S qb The first switch transistor S is turned on while controlling qa and turn off the target second switch transistor S qb is turned on for a first predetermined time period, the target first switch transistor S of the target switch transistor unit is turned on. qa is controlled to be on for a second predetermined length of time, and the target first switch transistor S qa The second switch transistor S is turned on while controlling the qband controlling the switch transistors of the remaining switch transistor units except for the target switch transistor unit to remain off during the operation cycle, where the target switch transistor unit is the switch transistor unit corresponding to the battery module numbered q (corresponding to battery module q in FIG. 3). The sum of the first predetermined time length and the second predetermined time length is equal to or less than the operation cycle. Thus, during each operation cycle of the switch transistors, the control module can complementarily control the target first switch transistor and the target second switch transistor to be turned on, and control the remaining first switch transistors and the remaining second switch transistors to remain off, so that the transitional energy storage module can balance the battery modules numbered p to q via the target first switch transistor or the target second switch transistor.

[0042] In one embodiment, the target first switch transistor S qa , target second switch transistor S qb During the on signal, the target first switch transistor S qa and the target second switch transistor S qb A dead time is provided to prevent these from being turned on at the same time.

[0043] In one embodiment, the target first switch transistor S qa , target second switch transistor S qb and the balanced current i flowing through the inductor L. L is shown in FIG. 4, where the operation modes of the balanced system 100 include mode 1 and mode 2. However, I L,avg is the equilibrium current i L is the average value of

[0044] In mode 1, that is, in the period from t0 to t2, the target second switch transistor S qb is turned on for a first predetermined length of time, and the target first switch transistor S qais turned off and the first predetermined length of time is qb Duty cycle D and operating cycle T s and the first predetermined time period is DT s and the equilibrium current i L increases linearly, where the equivalent circuit of the balancing system 100 is shown in FIG. 5, and the transitional energy storage module 102 balances battery module p through battery module q-1.

[0045] In mode 2, that is, in the period from t2 to t4, the target first switch transistor S qa is turned on for a second predetermined length of time, and the target second switch transistor S qb is turned off, and ignoring dead time, the second predetermined length of time is the difference between the operating cycle and the first predetermined length of time, i.e., the second predetermined length of time is (1-D)T s and the equilibrium current i L decreases linearly, where the equivalent circuit of the balancing system 100 is shown in FIG. 6, and the transitional energy storage module 102 balances battery module p through battery module q.

[0046] As shown in FIG. 4, the period from t0 to t1 and the period from t2 to t3 are both dead times.

[0047] The voltages of battery modules p to q are V p ~V q and the voltage of the transitional energy storage module 102 is V t and the relationship between the voltages is JPEG0007770563000002.jpg52161.

[0048] To make it understandable, In the case of JPEG0007770563000003.jpg22161, the equilibrium current i L increases, for example, the equilibrium current i L The average value of I L,avg increases, and conversely, In the case of JPEG0007770563000004.jpg22161, the equilibrium current i L decreases, e.g., the equilibrium current i L The average value of I L,avg As is clear from the above analysis, the equilibrium current i L is the target second switch transistor S qb is related to the duty cycle D of the

[0049] Based on any of the above embodiments, the control module 103 may further select a target second switch transistor S qb By adjusting the duty cycle D of the inductor L, the balanced current i L For example, the control module 103 may further adjust the target second switch transistor S qb By adjusting the duty cycle D of the inductor L, the balanced current i L The average value of I L,avg Thus, the system can adjust the duty cycle of the target second switch transistor to adjust the balancing current flowing through the inductor, thereby achieving accurate control of the balancing current.

[0050] In one embodiment, the control module 103 further determines the balancing current i based on the remaining capacity of each target battery module. L Determine the target value of the balanced current i L This is used to determine the target value of the duty cycle D based on the target value of

[0051] In one embodiment, the control module 103 includes a regulator, which regulates the balancing current i L The target value of and the balanced current i L It is used to adjust the target value of the duty cycle D based on the current value of I. For example, the regulator L,avg Target value of and I L,avg It is used to adjust the target value of the duty cycle D based on the current value of I. L,avg is the equilibrium current i L, where the type of the regulator is not particularly limited, and for example, the regulator may include, but is not limited to, a proportional-integral regulator, a proportional-derivative regulator, etc. In this way, the system can use the regulator to adjust the target value of the duty cycle and further adjust the balancing current, thereby achieving accurate control of the balancing current.

[0052] In one embodiment, continuing with the example of FIG. 2, the control module 103 includes a battery management unit 1031 , a regulator 1032 , a driving unit 1033 , a current sampling unit 1034 and a voltage sampling unit 1035 .

[0053] The current sampling unit 1034 is I L,avg The battery management unit 1031 is used to sample the current value of I based on the remaining capacity of each battery module, and determines a plurality of target battery modules based on the remaining capacity of each target battery module. L,avg Target value I ref and the regulator 1032 is used to determine I L,avg The current value of and I L,avg Target value I ref and generating a switch duty signal having the target value of the duty cycle D.

[0054] The battery management unit 1031 is further used to generate an on / off signal for the switch module 101, and the driving unit 1033 is used to control the switch of the switch module 101 to be on and / or off according to the on / off signal and the switch duty signal.

[0055] In one embodiment, the target battery modules include battery modules numbered p to q, that is, the target battery modules include battery module p to battery module q. The control module 103 further calculates the voltage and the target second switch transistor S of each target battery module. qbDetermine the number k based on the range of values ​​of the duty cycle D, and select the transitional energy storage battery with the number k (transitional energy storage battery A in FIG. 2). k 2) corresponding to the third switch (the third switch K tk and turning on the third switches corresponding to the remaining transitional energy storage batteries except for the transitional energy storage battery numbered k, and turning off the third switches corresponding to the remaining transitional energy storage batteries except for the transitional energy storage battery numbered k. Thus, the control module can determine the number k, i.e., the target transitional energy storage battery, by comprehensively considering the voltage of each target battery module and the value range of the duty cycle of the target second switch transistor, and control the third switch corresponding to the transitional energy storage battery numbered k to be on, and control the remaining third switches to be off, so that each target transitional energy storage battery can balance multiple target battery modules through the turned-on third switch.

[0056] In one embodiment, still referring to FIG. 2 as an example, transitional energy storage battery A1 to transitional energy storage battery A j The voltages are V t1 ~V tj The voltage sampling unit 1035 is connected to the transitional energy storage battery A1 to the transitional energy storage battery A j Voltage V t1 ~Voltage V tj is used to sample the

[0057] In one embodiment, the voltage of the transitional energy storage module 102 (i.e., target transitional energy storage battery A1 to target transitional energy storage battery A k The sum of the voltages of JPEG0007770563000005.jpg21161.

[0058] The voltages of battery modules p to q are V p ~V q and the voltage of the transitional energy storage module 102 is V t and the relationship between the voltages is JPEG0007770563000006.jpg23161.

[0059] In one embodiment, the value range of the duty cycle D is set to 0.1 to 0.9 to avoid a duty cycle that is too high or too low, which affects the efficiency of equalization. In this case, the voltage V of the transitional energy storage module 102 t is the condition Meets JPEG0007770563000007.jpg23161.

[0060] from now, JPEG0007770563000008.jpg23161 can be obtained, and the value range of the number k can then be determined, and the target transitional energy storage battery can be determined.

[0061] Based on any of the above embodiments, as shown in FIG. 7 , a battery cluster 200 includes battery modules 1 to 5, each of which includes two cells, where battery module 1 includes cells B1 and B2, battery module 2 includes cells B3 and B4, battery module 3 includes cells B5 and B6, battery module 4 includes cells B7 and B8, and battery module 5 includes cells B9 and B10. 10 Includes.

[0062] For example, the control module 103 sets battery modules 3 and 4 as first target battery modules whose balancing category is discharge, and battery modules 1 and 2 as second target battery modules whose balancing category is charge.

[0063] When balancing the battery modules 3 and 4, the control module 103 sets the target first switch K of the first switch unit corresponding to the battery module 4. 4a , and the target second switch K of the second switch unit corresponding to the battery module 3 is controlled to be on. 3b Controls on and K 4a The remaining first switches except for K are controlled to be off, and 3bIt is used to control the remaining second switches excluding the first one to be turned off.

[0064] In each operation cycle of the switch transistor, the control module 103 further controls the target second switch transistor S of the target switch transistor unit corresponding to the battery module 4. 4b is controlled to be on for a first predetermined length of time, and a target second switch transistor S 4b The first switch transistor S is turned on while controlling 4a and turn off the target second switch transistor S 4b is turned on for a first predetermined time period, the target first switch transistor S of the target switch transistor unit corresponding to the battery module 4 is turned on. 4a is controlled to be on for a second predetermined length of time, and the target first switch transistor S 4a The second switch transistor S is turned on while controlling the 4b Control off and S 4a , S 4b The remaining switch transistors except for the first one are controlled to remain off during the operation cycle.

[0065] Target first switch transistor S 4a , target second switch transistor S 4b and the balanced current i flowing through the inductor L. L is shown in FIG. 8, where the operation modes of the balancing system 100 include mode 1 and mode 2, and the balancing current i L The average value of I L,avg <0.

[0066] In mode 1, that is, in the period from t0 to t2, the target second switch transistor S 4b is turned on for a first predetermined length of time, and the target first switch transistor S 4a is turned off and the first predetermined length of time is 4b The duty cycle D1 and operating cycle T s and the length of the first predetermined time is D1Ts and the equilibrium current i L increases linearly, in which case the equivalent circuit of the balanced system 100 is shown in FIG. 9, and the transitional energy storage module 102 is used to store the electrical energy released by the battery module 3.

[0067] In mode 2, that is, in the period from t2 to t4, the target first switch transistor S 4a is turned on for a second predetermined length of time, and the target second switch transistor S 4b is turned off, and ignoring dead time, the second predetermined time length is the difference between the operating cycle and the first predetermined time length, i.e., the second predetermined time length is (1-D1)T s and the equilibrium current i L decreases linearly, in which case the equivalent circuit of the balancing system 100 is shown in FIG. 10, and the transitional energy storage module 102 is used to store the electrical energy released by the battery modules 3, 4.

[0068] When balancing the battery modules 1 and 2, the control module 103 sets the target first switch K of the first switch unit corresponding to the battery module 2. 2a , and the target second switch K of the second switch unit corresponding to the battery module 1 is controlled to be on. 1b Controls on and K 2a The remaining first switches except for K are controlled to be off, and 1b It is used to control the remaining second switches excluding the first one to be turned off.

[0069] In each operation cycle of the switch transistor, the control module 103 further controls the target second switch transistor S of the target switch transistor unit corresponding to the battery module 2. 2b is controlled to be on for a first predetermined length of time, and a target second switch transistor S 2b The first switch transistor S is turned on while controlling 2a and turn off the target second switch transistor S 2bis turned on for a first predetermined length of time, the target first switch transistor S of the target switch transistor unit corresponding to the battery module 2 is turned on. 2a is controlled to be on for a second predetermined length of time, and the target first switch transistor S 2a The second switch transistor S is turned on while controlling the 2b Control off and S 2a , S 2b The remaining switch transistors except for the first one are controlled to remain off.

[0070] Target first switch transistor S 2a , target second switch transistor S 2b and the balanced current i flowing through the inductor L. L is shown in FIG. 11, where the operation modes of the balancing system 100 include mode 1 and mode 2, and the balancing current i L The average value of I L,avg >0.

[0071] In mode 1, that is, in the period from t0 to t2, the target second switch transistor S 2b is turned on for a first predetermined length of time, and the target first switch transistor S 2a is turned off and the first predetermined length of time is 2b The duty cycle D2 and operating cycle T s and the first predetermined time period is D2T s and the equilibrium current i L increases linearly, in which case the equivalent circuit of the balancing system 100 is shown in FIG. 12, and the transitional energy storage module 102 releases electrical energy to charge the battery module 1.

[0072] In mode 2, that is, in the period from t2 to t4, the target first switch transistor S 2a is turned on for a second predetermined length of time, and the target second switch transistor S 2bis turned off, and ignoring dead time, the second predetermined time length is the difference between the operating cycle and the first predetermined time length, i.e., the second predetermined time length is (1-D2)T s and the equilibrium current i L decreases linearly, in which case the equivalent circuit of the balancing system 100 is shown in FIG. 13, and the transitional energy storage module 102 is used to release electrical energy to charge the battery modules 1 and 2.

[0073] The control module 103 is omitted from any of FIGS. 3, 5, 6, 7, 9, 10, 12, and 13.

[0074] In describing the present disclosure, any orientations or positional relationships indicated by the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," etc., are based on the orientations or positional relationships shown in the drawings, and are intended merely to facilitate the description of the present disclosure, and do not indicate or imply that such devices or elements have a particular orientation or are configured and operated in a particular orientation, and therefore should not be understood as limiting the present disclosure.

[0075] It should also be understood that the terms "first" and "second" are used for descriptive purposes only and do not indicate or imply the relative importance or number of technical features shown. Thus, a feature qualified as "first" or "second" can explicitly or implicitly include one or more features. In the description of this disclosure, "plurality" means two or more unless otherwise specifically limited.

[0076] In the present disclosure, unless otherwise clearly specified and limited, the terms "attached," "coupled," "connected," "fixed," and the like should be understood in a broad sense. For example, they may refer to a fixed connection, a detachable connection, or an integral connection, a mechanical connection, or an electrical connection, a direct connection, or an indirect connection via an intermediate medium, an internal communication between two elements, or an interactive relationship between two elements. Those skilled in the art can understand the specific meanings of the above terms in the present disclosure according to specific circumstances.

[0077] Although the embodiments of the present disclosure have been shown and described above, it should be understood that the above-described embodiments are illustrative and do not limit the present disclosure, and those skilled in the art may make changes, modifications, substitutions, and variations to the above-described embodiments within the scope of the present disclosure.

Claims

1. A battery cluster balancing system, wherein the battery cluster includes a plurality of battery modules, and any two adjacent battery modules are connected in series; the balancing system includes a switch module, a transitional energy storage module, and a control module; the switch module is connected to each of the battery modules; the transitional energy storage module is coupled to the switch module; The control module is used to control the on and / or off of the switches of the switch module, so that the transitional energy storage module balances a plurality of consecutive target battery modules through the on switches of the switch module; the switch module includes a switch transistor unit, a switch unit, a third switch, and an inductor; There is a one-to-one correspondence between the switch transistor unit, the switch unit, and the battery module; Any two adjacent switch transistor units are connected in series, and each switch transistor unit includes a first switch transistor and a second switch transistor; a first end of the first switch transistor is connected to a positive electrode of the corresponding battery module, a second end of the first switch transistor is connected to a first end of the second switch transistor, and a second end of the second switch transistor is connected to a negative electrode of the corresponding battery module; Each of the switch units includes a first switch and a second switch, a first end of each of the first switches connected to the second end of the inductor, a second end of each of the first switches connected to the second end of the first switch transistor of the corresponding switch transistor unit, a first end of each of the second switches connected to the negative electrode of the transitional energy storage module, and a second end of each of the second switches connected to the second end of the second switch transistor of the corresponding switch transistor unit; The transitional energy storage module includes a plurality of transitional energy storage batteries, and any two adjacent transitional energy storage batteries are connected in series; There is a one-to-one correspondence between the third switches and the transitional energy storage batteries, and a first end of each of the third switches is connected to a positive electrode of the corresponding transitional energy storage battery, and a second end of each of the third switches is connected to a first end of the inductor; Battery cluster balancing system.

2. The battery cluster includes m battery modules, and the m battery modules are consecutively numbered from 1 to m, the negative electrode of the battery module numbered 1 is the negative electrode of the battery cluster, the positive electrode of the battery module numbered m is the positive electrode of the battery cluster, and the target battery module includes the battery modules numbered p to q, where 1≦p≦q≦m; 2. The system of claim 1, wherein the control module is further used to control a target first switch of a first switch unit and a target second switch of a second switch unit to be on, control the remaining first switches except for the target first switch to be off, and control the remaining second switches except for the target second switch to be off, wherein the first switch unit is the switch unit corresponding to the battery module numbered q, and the second switch unit is the switch unit corresponding to the battery module numbered p.

3. 3. The system of claim 2, wherein in each operating cycle of switch transistors, the switch transistors include the first switch transistor and the second switch transistor, and the control module is further configured to: control a target second switch transistor of a target switch transistor unit to be on for a first predetermined length of time; control a target first switch transistor of the target switch transistor unit to be off while controlling the target second switch transistor to be on; control the target first switch transistor to be on for a second predetermined length of time after controlling the target second switch transistor to be on for the first predetermined length of time; control the target second switch transistor to be off while controlling the target first switch transistor to be on; and control the switch transistors of the remaining switch transistor units except for the target switch transistor unit to remain off in the operating cycle, wherein the target switch transistor unit is the switch transistor unit corresponding to the battery module numbered q.

4. 4. The system of claim 3, wherein the control module is further adapted to adjust a duty cycle of the target second switch transistor to adjust a balanced current through the inductor.

5. 5. The system of claim 4, wherein the control module is further configured to determine a target value of the balancing current based on the remaining power of each of the target battery modules, and to determine a target value of the duty cycle based on the target value of the balancing current.

6. 6. The system of claim 5, wherein the control module includes a regulator, the regulator being adapted to adjust the target value of the duty cycle based on the target value of the balancing current and the current value of the balancing current.

7. the transitional energy storage module includes j transitional energy storage batteries, the j transitional energy storage batteries are consecutively numbered from number 1 to number j, the negative electrode of the transitional energy storage battery number 1 is the negative electrode of the transitional energy storage module, the positive electrode of the transitional energy storage battery number k is the positive electrode of the transitional energy storage module, the target transitional energy storage battery includes the transitional energy storage batteries numbered 1 to number k, the target transitional energy storage battery is the transitional energy storage battery for balancing the target battery module, where 1≦k≦j; 5. The system of claim 4, wherein the control module is further used for determining a number k according to a range of values ​​of the voltage and the duty cycle of each of the target battery modules, and controlling a third switch corresponding to the transitional energy storage battery of the number k to be on, and controlling a third switch corresponding to the remaining transitional energy storage batteries excluding the transitional energy storage battery of the number k to be off.

8. The system according to any one of claims 1 to 7, wherein the control module is further used to obtain average values ​​of remaining power of the plurality of consecutively arranged candidate battery modules in response to a variance value between the remaining power of each of the battery modules being greater than a predetermined threshold, and to set the plurality of candidate battery modules corresponding to the maximum average value as first target battery modules whose balance category is discharge, and to set the plurality of candidate battery modules corresponding to the minimum average value as second target battery modules whose balance category is charge.

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