Battery short-circuit protection circuit, battery cluster and parallel system

Abstract

The utility model provides a battery short-circuit protection circuit, a battery cluster and a parallel system. The battery short-circuit protection circuit comprises a switch power module, a current acquisition module, a voltage amplification module, a reference power supply module, a voltage comparison module, an AFE chip and a microcontroller. The current acquisition module acquires the current of the switching power module and converts the current into a voltage signal, the voltage signal is input into the voltage amplification module for amplification, and then the voltage signal and the output voltage of the reference power supply module are input into the voltage comparison module for comparison, and the output is used as the input of the microcontroller; the microcontroller outputs a corresponding control signal to control the turn-off of a switch in the switch power module; meanwhile, the voltage signal is input to the AFE chip, and the AFE chip outputs a corresponding control signal to control the on and off of a switch in the switch power module. According to the battery short-circuit protection circuit, the battery cluster and the parallel system, a double short-circuit protection function can be realized, and rapid protection and comprehensive protection can be realized, so that a battery cell and a switch tube are prevented from being damaged.

Description

Technical Field

[0001] This utility model relates to the field of energy storage technology, and in particular to a battery short-circuit protection circuit, a battery cluster and a parallel system. Background Technology

[0002] In existing technologies, batteries, especially energy storage batteries, may catch fire during use, and the most common cause of fire is a short circuit between the positive and negative terminals. Existing protection methods are slow to disconnect the current loop and can generate excessive current, which can easily damage the battery cells and switching components such as MOSFETs in the circuit. Utility Model Content

[0003] The purpose of this invention is to provide a battery short-circuit protection circuit to solve the problems of slow response and low reliability in the aforementioned prior art for battery short-circuit protection.

[0004] This invention provides a battery short-circuit protection circuit, including a microprocessor short-circuit control circuit and an AFE short-circuit control circuit. The microprocessor short-circuit control circuit includes a switching power module, a current acquisition module, a voltage amplification module, a reference power supply module, a voltage comparison module, and a microcontroller. The AFE short-circuit control circuit includes the switching power module, the current acquisition module, and an AFE chip. The current acquisition module acquires the current from the switching power module and converts it into a voltage signal. This signal is amplified by the voltage amplification module and compared with the output voltage of the reference power supply module. The resulting output is used as the input to the microcontroller, which outputs a corresponding control signal to turn off the switch in the switching power module. Simultaneously, the voltage signal is input to the AFE chip, which outputs a corresponding control signal to turn on and off the switch in the switching power module.

[0005] Furthermore, the switch in the switching power module is any one of a transistor, a MOSFET, or an IGBT.

[0006] Furthermore, the switching power module includes a charging module and a discharging module.

[0007] Furthermore, the current acquisition module is a resistor.

[0008] Furthermore, the voltage amplification module includes a differential amplifier and a voltage follower connected to the output of the differential amplifier.

[0009] Furthermore, the voltage comparison module includes an operational amplifier and a switching circuit.

[0010] Furthermore, the reference power supply module is used to obtain a stable preset voltage value.

[0011] The present invention also discloses a battery cluster, comprising N batteries and the aforementioned short-circuit protection circuit, wherein each short-circuit protection circuit corresponds to one battery, one pole of the N batteries is connected together to form a first terminal, and the other poles of the N batteries are connected in series with their respective short-circuit protection circuits and then connected together to form a second terminal; wherein N is an integer greater than or equal to 2.

[0012] The present invention also discloses a parallel battery cluster system, comprising M of the aforementioned battery clusters, wherein the first ends of each battery cluster are connected together, and the second ends of each battery cluster are connected together, wherein M is an integer greater than or equal to 2.

[0013] The battery short-circuit protection circuit, battery cluster, and parallel system of this utility model can provide timely and dual protection for a single battery. For the parallel system, when a single battery is short-circuited, all parallel batteries can be controlled to perform short-circuit protection actions simultaneously, and dual short-circuit protection functions can be achieved, thereby ensuring that the battery cells and switching transistors are not damaged, thus solving the problems mentioned in the background art. Attached Figure Description

[0014] Figure 1 This is a block diagram of a battery short-circuit protection circuit according to an embodiment of the present invention.

[0015] Figure 2 This is a topology diagram of a battery short-circuit protection circuit according to an embodiment of the present invention;

[0016] Figure 3 This is a schematic diagram of the connection between a single battery and a battery short-circuit protection circuit according to an embodiment of the present invention.

[0017] Figure 4 This is a schematic diagram of a battery cluster consisting of two batteries connected in parallel according to an embodiment of the present invention.

[0018] Figure 5 This is a parallel battery cluster system according to an embodiment of the present invention.

[0019] Explanation of key component symbols:

[0020] 1. Battery short circuit protection; 2. Battery; 11. Switching power module; 12. Current acquisition module; 13. Voltage amplification module; 14. Reference power supply module; 15. Voltage comparison module; 16. AFE chip; 17. Microcontroller.

[0021] The following detailed description, in conjunction with the accompanying drawings, will further illustrate this utility model. Detailed Implementation

[0022] To facilitate understanding of this utility model, a more comprehensive description will be given below with reference to the accompanying drawings. Several embodiments of this utility model are shown in the drawings. However, this utility model can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this utility model will be more thorough and complete.

[0023] It should be noted that when a component is said to be "fixed to" another component, it can be directly on the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0025] Please see Figure 1 The diagram shows a battery short-circuit protection circuit 1 in the first embodiment of the present invention, including a switching power module 11, a current acquisition module 12, a voltage amplification module 13, a reference power supply module 14, a voltage comparison module 15, an AFE chip 16, and a microcontroller 17.

[0026] The current acquisition module 2 is connected to the switching power module 11. The current acquisition module 2 acquires the current from the switching power module 11 and converts it into a voltage signal. This signal is then amplified by the voltage amplification module 13 and compared with the output voltage of the reference power supply module 14 by the voltage comparison module 15. The output of the voltage comparison module 15 serves as the input to the microcontroller 17. The microcontroller 17 outputs a corresponding control signal to control the switch in the switching power module 11 to turn off, thus achieving battery short-circuit protection. Simultaneously, the aforementioned voltage signal is input to the AFE chip 16 for processing. The AFE chip 16 outputs a corresponding control signal to control the switch in the switching power module 11 to turn on and off, thereby achieving the connection and disconnection of the battery circuit and providing battery short-circuit protection when turned off. In use, such as... Figure 3 As shown, the switching power module 11 is connected to the negative terminal of the battery 2 (in other embodiments, the switching power module 11 is connected to the positive terminal BAT+ of the battery 2, correspondingly, the aforementioned Figure 2(The "BAT-" in the original text is replaced with "BAT+"). Since the disconnection control of the switch in the switching power module 11 can be achieved through both the AFE chip 16 and the microcontroller 17, dual protection against battery short circuits can be achieved, increasing the reliability of battery operation. Furthermore, due to the hardware protection circuit where the microcontroller 17 is located, the signal transmission speed is faster, the microcontroller 17 reacts faster, and the time required to disconnect the switch in the switching power module 11 is shorter, thereby improving the safety of battery use.

[0027] The switch in the switching power module 11 can be a transistor, MOSFET, IGBT, etc.; the reference power module 14 is used to obtain a stable preset voltage value.

[0028] Understandably, the aforementioned battery short-circuit protection circuit 1 includes a microprocessor short-circuit control circuit and an AFE short-circuit control circuit. The microprocessor short-circuit control circuit includes a switching power module 11, a current acquisition module 12, a voltage amplification module 13, a reference power supply module 14, a voltage comparison module 15, and a microcontroller 17; the AFE short-circuit control circuit includes a switching power module 11, a current acquisition module 12, and an AFE chip 16; the connection relationships and working processes will not be described in detail.

[0029] Please see Figure 2 The diagram illustrates a battery short-circuit protection circuit 1 according to a second embodiment of the present invention. The switching power module 11 includes a bidirectional switch. In one embodiment, the bidirectional switch includes a first switching transistor Q1, a second switching transistor Q2, a first diode D1, and a second diode D2. The first switching transistor Q1 and the second switching transistor Q2 can both be transistors, MOSFETs, or IGBTs. The first diode D1 is connected in reverse parallel across the two ends of the first switching transistor Q1, and the second diode D2 is connected in reverse parallel across the two ends of the second switching transistor Q2. In another embodiment, the switching power module 11 further includes a first transient voltage suppressor diode ZD1 and a second transient voltage suppressor diode ZD2. The first transient voltage suppressor diode ZD1 is connected in parallel across the two ends of the first switching transistor Q1, and the second transient voltage suppressor diode ZD2 is connected in parallel across the two ends of the second switching transistor Q2.

[0030] Combination Figure 3 When charging battery 2, current flows from the negative terminal BAT- of the battery through the second diode D2 and the first switch Q1. The first transient voltage suppressor Zener diode ZD1 can clamp the excessively high voltage across the first switch Q1 to a safe level. When discharging battery 2, current flows through the first diode D1 and the second switch Q2 to the negative terminal BAT- of the battery. The second transient voltage suppressor Zener diode ZD2 can clamp the excessively high voltage across the second switch Q2 to a safe level.

[0031] In summary, based on the different functions of battery charging and discharging, the switching power module 11 can be divided into a charging module and a discharging module. The charging module is used to charge the battery, and the discharging module is used to discharge the battery. Understandably, in one embodiment, the charging module includes a second diode D2 and a first switch Q1 connected in series therewith; the discharging module includes a first diode D1 and a second switch Q2 connected in series therewith. In another embodiment, the charging module includes a second diode D2 and a first switch Q1 connected in series therewith, and a first transient voltage suppressor Zener diode ZD1 connected in parallel across the first switch Q1; the discharging module includes a first diode D1 and a second switch Q2 connected in series therewith, and a second transient voltage suppressor Zener diode ZD2 connected in parallel across the second switch Q2.

[0032] In other embodiments, the bidirectional switch can be a relay, circuit breaker, or any other device that enables bidirectional flow of current through it.

[0033] Please continue reading. Figure 2 The current acquisition module 12 includes a first resistor R1, which is connected in series with the switching power module 11 and the negative terminal BAT- of the battery 2. Specifically, the first resistor R1 is connected in series with the negative terminal BAT- of the battery 2 (corresponding to...). Figure 3In other embodiments, the switching power module 11 can be connected in series between the first resistor R1 and the negative terminal BAT- of the battery 2. According to Ohm's law, the first resistor R1 converts the current flowing through the negative terminal BAT- of the battery 2 (i.e., the current flowing through the battery 2) into a voltage signal, which is then input into the AFE chip 16 and the voltage amplification module 13, respectively. In one embodiment, the voltage amplification module 13 includes a differential amplifier U1 and a voltage follower U2. The output terminal of the differential amplifier U1 is connected to the input terminal of the voltage follower U2. The aforementioned voltage signal is input to the input terminal of the differential amplifier U1, and after passing through the differential amplifier U1 and the voltage follower U2, it serves as the first input terminal of the voltage comparison module 15. The reference power supply module 14 includes a first power supply V1, a second resistor R2, a third resistor R3, a fourth resistor R4, a three-terminal regulator U4, and a ground wire GND. The first power supply V1, the second resistor R2, the third resistor R3, the fourth resistor R4, and the ground wire GND are connected in series. The input terminal of the three-terminal regulator U4 is connected to the common terminal of the third resistor R3 and the fourth resistor R4. The ground terminal of the three-terminal regulator U4 is grounded to the ground wire GND. The output terminal of the three-terminal regulator U4 is connected to the common terminal of the second resistor R2 and the third resistor R3. The output terminal of the three-terminal regulator U4 (output voltage V2) serves as the second input terminal of the voltage comparison module 15. In one embodiment... In the voltage comparison module 15, there are operational amplifier U3, third power supply V3, fifth resistor R5, third switch Q3 and ground GND. The third power supply V3, fifth resistor R5, third switch Q3 and ground GND are connected in series. The series connection of the third power supply V3, fifth resistor R5, third switch Q3 and ground GND is collectively referred to as the switching circuit. The output terminal of operational amplifier U3 is connected to the control terminal of third switch Q3. The first input terminal and the second input terminal of voltage comparison module 15 are the first input terminal and the second input terminal of operational amplifier U3. The output terminal (current inflow terminal) of third switch Q3 is connected to the input terminal of microcontroller 17. The two output terminals of AFE chip 16 and the two output terminals of microcontroller 17 are respectively connected to the control terminals of first switch Q1 and second switch Q2. AFE chip 16 is used to control the on and off of first switch Q1 and second switch Q2. Microcontroller 17 is used to control the off (turn off) of first switch Q1 and second switch Q2.

[0034] In one embodiment, when a short circuit occurs in the battery, i.e., the positive and negative terminals of the battery are connected together, the current flowing through the positive / negative terminals of the battery (i.e., the current flowing through the battery) exceeds a certain current threshold. Correspondingly, the voltage across the current acquisition module 12 exceeds a certain voltage threshold, and the output voltage of the voltage amplification module 13 (i.e., the output voltage of the voltage follower U2) is greater than the output voltage V2 of the reference power supply module 14 (a preset voltage value; i.e., the output voltage V2 of the three-terminal regulator U4). This causes the output of the operational amplifier U3 in the voltage comparison module 15 to be high, causing the third switch Q3 to conduct. When the circuit is open, the output of the third switch Q3 is pulled low, becoming a low level. This means the input of the microcontroller 17 is low, and the output of the microcontroller 17 is low, controlling the first switch Q1 and the second switch Q2 to disconnect, thereby achieving battery short-circuit protection. At the same time, if the current flowing through the positive / negative terminal of the battery exceeds a certain current threshold, the voltage across the current acquisition module 12 exceeds a certain voltage threshold. The current acquisition module 12 is input to the AFE chip 16, and the output of the AFE chip 16 becomes low, controlling the first switch Q1 and the second switch Q2 to disconnect, which can also achieve battery short-circuit protection.

[0035] Here, AFE stands for Analog Front End; in one embodiment, the AFE chip 16 is model SH367309U; the microcontroller 17 is model GD32F305; understandably, the AFE chip 16 and the microcontroller 17 can also be other models.

[0036] Please see Figure 3 The diagram illustrates the connection between a single battery and the battery short-circuit protection circuit 1. Specifically, the negative terminal (-) of the battery is connected in series with the battery short-circuit protection circuit 1. More specifically, the negative terminal (-) of the battery 2 is connected in series with the switching power module 11 in the battery short-circuit protection circuit 1. In other embodiments, the positive terminal (+) of the battery 2 is connected in series with the battery short-circuit protection circuit 1. More specifically, the positive terminal (+) of the battery 2 is connected in series with the switching power module in the battery short-circuit protection circuit 1.

[0037] Please see Figure 4The diagram illustrates a battery cluster consisting of two batteries connected in parallel. Specifically, the positive terminals of the two batteries 2 are connected together, and the negative terminals of the two batteries are connected together after being connected in series with their respective switching power modules 11. Each battery is protected against a short circuit by its own battery short-circuit protection circuit 1. In other embodiments, the two batteries 2 communicate with each other. When one battery 2 short-circuits, all battery short-circuit protection circuits 1 activate, controlling their respective switching power modules 11 to disconnect, thereby cutting off the connection between the positive and negative terminals of the battery 2 and achieving battery short-circuit protection. Understandably, in other embodiments, the positive and negative terminals of the battery 2 can be interchanged; that is, two switching power modules 11 are connected in series with the positive terminals of their respective batteries 2, and the negative terminals of the two batteries 2 are connected together.

[0038] Understandably, for a battery cluster consisting of N batteries connected in parallel (N being an integer greater than or equal to 2), the positive terminals of each battery 2 are connected together, and the negative terminals of each battery are connected together in series with their respective switching power modules 11. Each battery is protected against short circuits through its own battery short-circuit protection circuit 1. In other embodiments, each battery 2 communicates with each other. When any one battery 2 short-circuits, all battery 2 short-circuit protection circuits 1 activate, controlling their respective switching power modules 11 to disconnect, thereby cutting off the connection between the positive and negative terminals of the battery 2, thus achieving battery short-circuit protection. Understandably, in other embodiments, the positive and negative terminals of the battery 2 can be interchanged, that is, each switching power module 11 is connected in series with the positive terminal of the corresponding battery 2, and the negative terminals of each battery 2 are connected together.

[0039] Please see Figure 5 This diagram illustrates a parallel battery cluster system (hereinafter referred to as a parallel system), which includes two battery clusters, namely a first battery cluster and a second battery cluster, connected in parallel. Specifically, the first terminal A of the first battery cluster is connected to the first terminal A of the second battery cluster, and the second terminal B of the first battery cluster is connected to the second terminal B of the second battery cluster. Each battery cluster contains two parallel batteries; the parallel connection method of the two batteries is described in [reference needed]. Figure 4Description. Understandably, the positive terminals of the two batteries in the first battery cluster are connected together, forming the first terminal A of the first battery cluster; the positive terminals of the two batteries in the second battery cluster are connected together, forming the first terminal A of the second battery cluster; the negative terminals of the two batteries in the first battery cluster are connected in series with their respective switching power modules 11 and then connected together, forming the second terminal B of the first battery cluster; the negative terminals of the two batteries in the second battery cluster are connected in series with their respective switching power modules 11 and then connected together, forming the second terminal B of the second battery cluster. Understandably, when the positive and negative terminals of battery 2 are interchanged, the negative terminals of the two batteries in the first battery cluster are connected together, forming the first terminal A of the first battery cluster; the negative terminals of the two batteries in the second battery cluster are connected in series with their respective switching power modules 11 and then connected together, forming the second terminal B of the first battery cluster; the positive terminals of the two batteries in the second battery cluster are connected in series with their respective switching power modules 11 and then connected together, forming the second terminal B of the second battery cluster.

[0040] Understandably, for a parallel battery cluster system containing M battery clusters (M being an integer greater than or equal to 2), there are M battery clusters, each containing N batteries connected in parallel. The M battery clusters are interconnected, meaning the first terminals (A) of each cluster are connected, and the second terminals (B) of each cluster are connected. The parallel connection method of the N batteries in each cluster is described above. Understandably, the positive terminals of the N batteries in each cluster are connected together, which is the first terminal (A) of each cluster. The negative terminals of the N batteries in each cluster are connected in series with their respective switching power modules 11, which is the second terminal (B) of each cluster. Understandably, when the positive and negative terminals of battery 2 are interchanged, the negative terminals of the N batteries in each cluster are connected together, which is the first terminal (A) of each cluster. The positive terminals of the N batteries in each cluster are connected in series with their respective switching power modules 11, which is the second terminal (B) of each cluster.

[0041] The aforementioned parallel battery cluster system with M battery clusters allows communication between each battery cluster and between the N batteries within each battery cluster. When any battery experiences a short circuit, or when an external circuit connected to the positive / negative terminal of a battery experiences a short circuit, all batteries can be controlled to disconnect their respective switching power modules 11, thereby cutting off the circuit in which the battery is located and achieving short circuit protection.

[0042] The beneficial effects of this utility model are as follows:

[0043] (1) Parallel short circuit protection of multiple batteries: When a short circuit occurs in a single battery, all parallel batteries can be protected through communication.

[0044] (2) Dual protection: In the event of a fault in the first short-circuit protection circuit, the second protection circuit will operate normally, achieving stable short-circuit protection and improving safety and reliability.

[0045] (3) Faster hardware short circuit protection: The hardware short circuit protection transmits faster, the microcontroller responds faster, and the disconnection time is shorter, which improves the safety of battery use.

[0046] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of this utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A battery short circuit protection circuit, characterized by, The short-circuit protection circuit comprises a microprocessor short-circuit control circuit and an AFE short-circuit control circuit; the microprocessor short-circuit control circuit comprises a switching power module, a current acquisition module, a voltage amplification module, a reference power supply module, a voltage comparison module and a microcontroller; the AFE short-circuit control circuit comprises the switching power module, the current acquisition module and an AFE chip; the current acquisition module acquires the current of the switching power module and converts it into a voltage signal, which is input to the voltage amplification module for amplification, and then, together with the output voltage of the reference power supply module, is input to the voltage comparison module for comparison, and the output after comparison is input to the microcontroller; the microcontroller outputs a corresponding control signal to control the turn-off of the switch in the switching power module; at the same time, the voltage signal is input to the AFE chip, and the AFE chip outputs a corresponding control signal to control the turn-on and turn-off of the switch in the switching power module.

2. The battery short protection circuit of claim 1, wherein The switch in the switching power module is any one of a triode, a MOS tube and an IGBT.

3. The battery short protection circuit of claim 1, wherein The switching power module comprises a charging module and a discharging module.

4. The battery short protection circuit of claim 1, wherein The current acquisition module is a resistor.

5. The battery short protection circuit of claim 1, wherein, The voltage amplification module comprises a differential amplifier and a voltage follower connected to the output of the differential amplifier.

6. The battery short protection circuit of claim 1, wherein The voltage comparison module comprises an operational amplifier and a switching circuit.

7. The battery short protection circuit of claim 1, wherein The reference power supply module is used to obtain a stable preset voltage value.

8. A battery cluster comprising N batteries, characterized in that, The short-circuit protection circuit of any one of claims 1-7 is further provided, and each short-circuit protection circuit corresponds to one battery; one pole of N batteries is connected together to form a first end, and the other pole of the N batteries is connected together after being respectively connected with the corresponding short-circuit protection circuit in series to form a second end; wherein N is an integer greater than or equal to 2.

9. A battery cluster and association system, characterized by M battery clusters of claim 8 are provided, and the first end of each battery cluster is connected together, and the second end of each battery cluster is connected together, wherein M is an integer greater than or equal to 2.

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