Protection circuit, battery management system and energy storage assembly

Abstract

The utility model discloses a protection circuit, a battery management system and an energy storage assembly, and relates to the technical field of protection circuits. The protection circuit comprises a first switch tube, a second switch tube, a third switch tube and a three-terminal fuse. When it is detected that the battery is abnormal, the main control circuit can output a control signal to the first switch tube, the first switch tube is controlled to be switched on, then the second switch tube is controlled to be switched on, and therefore the third switch tube is controlled to be switched on. At the moment, the first driving end and the second driving end of the three-end fuse are connected, namely, the first driving end of the three-end fuse is connected to the negative electrode of the battery, and the first connecting end of the three-end fuse is connected to the first power supply end, so that relatively strong voltage can be formed between the first connecting end and the first driving end of the three-end fuse and is continuously output to the three-end fuse; and the three-terminal fuse can be fused in a short time. According to the utility model, the three-terminal fuse can be controlled to actively fuse, a power supply is rapidly cut off, and the safety of the protection circuit is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of protection circuit, especially relates to a protection circuit, battery management system and energy storage assembly. BACKGROUND

[0002] With the development of battery technology, the application of battery in the field of electric vehicles, energy storage assembly and portable electronic equipment is increasingly widespread, and its safety and reliability are directly related to the life and property safety of users, becoming the core problem of concern.

[0003] However, the existing battery management system (BMS, Battery Management System) has the problem of misjudgment of protection circuit. When abnormal conditions such as voltage fluctuation or external interference occur, the BMS may fail to quickly cut off the circuit when the circuit is cut off, resulting in damage to the battery and other circuit elements by large current, and even causing safety problems such as short circuit, overheating or fire, seriously threatening personnel and property safety. UTILITY MODEL CONTENTS

[0004] The main purpose of the utility model is to provide a protection circuit, which aims to solve the problem that the existing battery management system fails to quickly cut off the circuit when abnormal conditions such as voltage fluctuation or external interference occur.

[0005] To achieve the above purpose, the protection circuit provided by the utility model is applied to a battery management system, which includes a first power supply end and a master control circuit, and the master control circuit is connected with the detection end of the battery. The protection circuit includes a first switch tube, a second switch tube, a third switch tube and a three-terminal fuse.

[0006] The controlled end of the first switch tube is connected with the first control end of the master control circuit, the first end of the first switch tube is grounded, the second end of the first switch tube is connected with the controlled end of the second switch tube, the first end of the second switch tube is connected with the power supply end of the protection circuit, the second end of the second switch tube is connected with the controlled end of the third switch tube, the first end of the third switch tube is connected with the first driving end of the three-terminal fuse, the second end of the third switch tube and the second driving end of the three-terminal fuse are connected with the negative electrode of the battery, the first connecting end of the three-terminal fuse is connected with the first power supply end, and the second connecting end of the three-terminal fuse is connected with the positive electrode of the battery.

[0007] In one embodiment, the first switching transistor is a first NMOS transistor, the second switching transistor is a first PMOS transistor, and the third switching transistor is a second NMOS transistor; the gate of the first NMOS transistor is connected to the first control terminal of the main control circuit, the source of the first NMOS transistor is grounded, the drain of the first NMOS transistor is connected to the gate of the first PMOS transistor, the source of the first PMOS transistor is connected to the power supply terminal of the protection circuit, the drain of the first PMOS transistor is connected to the gate of the second NMOS transistor, the drain of the second NMOS transistor is connected to the first driving terminal of the three-terminal fuse, and the source of the second NMOS transistor and the second driving terminal of the three-terminal fuse are connected to the negative terminal of the battery.

[0008] In one embodiment, the protection circuit further includes a first resistor, a second resistor, and a third resistor; one end of the first resistor is connected to the gate of the first NMOS transistor, and the other end of the first resistor is connected to the source of the first NMOS transistor; one end of the second resistor is connected to the gate of the first PMOS transistor, and the other end of the second resistor is connected to the source of the first PMOS transistor; one end of the third resistor is connected to the gate of the second NMOS transistor, and the other end of the third resistor is connected to the source of the second NMOS transistor.

[0009] In one embodiment, the protection circuit further includes a bidirectional transient voltage suppressor, one end of which is connected to the drain of the second NMOS transistor, and the other end of which is connected to the source of the second NMOS transistor.

[0010] In one embodiment, the protection circuit further includes a Zener diode; the negative terminal of the Zener diode is connected to the gate of the second NMOS transistor, and the positive terminal of the Zener diode is connected to the source of the second NMOS transistor.

[0011] In one embodiment, the protection circuit further includes a fourth resistor, a fifth resistor, a sixth resistor, and a first capacitor; one end of the fourth resistor is connected to the first control terminal of the main control circuit, and the other end of the fourth resistor is connected to the gate of the first NMOS transistor; one end of the fifth resistor is connected to the drain of the first NMOS transistor, and the other end of the fifth resistor is connected to the gate of the first PMOS transistor; one end of the sixth resistor and one end of the first capacitor are connected to the drain of the first PMOS transistor, the other end of the sixth resistor is connected to the gate of the second NMOS transistor, and the other end of the first capacitor is grounded.

[0012] This utility model also proposes a battery management system, including a first power supply terminal and a main control circuit, wherein the main control circuit is connected to the detection terminal of the battery; the battery management system also includes the protection circuit described above.

[0013] In one embodiment, the battery management system further includes:

[0014] Second power supply terminal;

[0015] A charge / discharge control circuit is provided, wherein a first terminal of the charge / discharge control circuit is connected to a second power supply terminal, a second terminal of the charge / discharge control circuit is connected to the first power supply terminal, a third terminal of the charge / discharge control circuit is connected to the negative terminal of the battery, and a controlled terminal of the charge / discharge control circuit is connected to a second control terminal of the main control circuit; the charge / discharge control circuit is used to control the charging / discharging of the battery.

[0016] The main control circuit is also used to control the operation / stop operation of the charge / discharge control circuit.

[0017] This invention also proposes an energy storage component, including a battery and a battery management system as described above.

[0018] In one embodiment, the energy storage component further includes:

[0019] The charger has an input terminal connected to an external AC power input terminal, an output terminal connected to a second power supply terminal, and a controlled terminal connected to the main control circuit; the charger is used to convert external AC power into DC power input.

[0020] The main control circuit is also used to control the charger's operation / stop; and / or

[0021] An inverter, wherein the input terminal of the inverter is connected to the second power supply terminal, the output terminal of the inverter is connected to the AC power output terminal, and the controlled terminal of the inverter is connected to the main control circuit; the inverter is used to convert DC power into AC power output.

[0022] The main control circuit is also used to control the operation / stop operation of the inverter.

[0023] This utility model provides a protection circuit for a battery management system, which includes a first power supply terminal and a main control circuit. The protection circuit includes a first switching transistor, a second switching transistor, a third switching transistor, and a three-terminal fuse. When the battery charging and discharging is normal, the main control circuit outputs a first level to the first switching transistor, controlling it to be in a turned-off state, which in turn controls the second switching transistor to be in a turned-off state, and consequently, the third switching transistor is also in a turned-off state. At this time, the first and second driving terminals of the three-terminal fuse are disconnected. If the current between the first and second connecting terminals does not exceed a preset value, the three-terminal fuse is in a normal connected state. When the battery charging and discharging is abnormal, a second level is output to the first switching transistor, controlling it to be turned on, which in turn controls the second switching transistor to be turned on, and consequently, the third switching transistor is also turned on. At this point, the first and second driving terminals of the three-terminal fuse are connected. The first driving terminal of the three-terminal fuse is connected to the negative terminal of the battery. Because the first connecting terminal of the three-terminal fuse is connected to the first power supply terminal, a strong voltage can be continuously output to the three-terminal fuse between the first connecting terminal and the first driving terminal, causing the three-terminal fuse to blow within a short time. Compared with existing technologies, even in the event of voltage fluctuations or external interference, the battery protection system can actively output a control signal to blow the three-terminal fuse and quickly cut off the power supply when it detects an abnormal battery condition. This invention significantly improves the safety of the battery protection system. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0025] Figure 1 A schematic diagram of an embodiment of the protection circuit provided by this utility model;

[0026] Figure 2 A schematic diagram of an embodiment of the energy storage component provided by this utility model.

[0027] Explanation of icon numbers:

[0028]

[0029] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0030] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0031] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0032] Furthermore, the use of terms such as "first" and "second" in this utility model is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this utility model.

[0033] It should be noted that existing battery management systems (BMS) have a problem with protection circuit misjudgment. When abnormal conditions such as voltage fluctuations or external interference occur, the BMS may fail to cut off the circuit in time when it should, resulting in a large current that damages the battery and other circuit components, or even causes safety problems such as short circuits, overheating or fire, seriously threatening the safety of people and property.

[0034] This utility model proposes a protection circuit.

[0035] Please see Figure 1 In one embodiment of this utility model, the protection circuit is applied to a battery management system, which includes a first power supply terminal and a main control circuit, the main control circuit being connected to the detection terminal of the battery. The protection circuit includes a first switch Q1, a second switch Q2, a third switch Q3, and a three-terminal fuse J.

[0036] The controlled terminal of the first switch Q1 is connected to the first control terminal of the main control circuit. The first terminal of the first switch Q1 is grounded. The second terminal of the first switch Q1 is connected to the controlled terminal of the second switch Q2. The first terminal of the second switch Q2 is connected to the power supply terminal of the protection circuit. The second terminal of the second switch Q2 is connected to the controlled terminal of the third switch Q3. The first terminal of the third switch Q3 is connected to the first driving terminal of the three-terminal fuse J. The second terminal of the third switch Q3 and the second driving terminal of the three-terminal fuse J are connected to the negative terminal of the battery. The first connection terminal of the three-terminal fuse J is connected to the first power supply terminal. The second connection terminal of the three-terminal fuse J is connected to the positive terminal of the battery.

[0037] In this embodiment, the three-terminal fuse J has a first connection terminal P4, a second connection terminal P5, a first driving terminal P3, and a second driving terminal P1, and may also include a ground terminal P2. The second driving terminal P1 is connected to the negative terminal of the battery. When the first driving terminal P3 is connected to the second driving terminal P1, i.e., when the first driving terminal P3 is connected to the negative terminal of the battery, the three-terminal fuse J can melt under a relatively high voltage. In this embodiment, when the current flowing through the circuit between the first connection terminal P4 and the second connection terminal P5 of the three-terminal fuse J is too large, the three-terminal fuse J will melt like a normal fuse. When the main control circuit detects an abnormal charging / discharging state of the battery or an abnormality in the circuit within the battery management system (such as an abnormality in the MOSFET of the charging / discharging control circuit), if the circuit cannot be cut off at this time, a control signal CON can be output to actively melt the three-terminal fuse J of the protection circuit to protect the charging / discharging safety of the battery. It should be noted that compared with other protection devices, the three-terminal fuse J has advantages such as low power consumption, fast response speed, and good protection effect.

[0038] In this embodiment, when the battery charging and discharging are normal, the main control circuit can output a first level to the first switch Q1, controlling the first switch Q1 to be in the off state, thereby controlling the second switch Q2 to be in the off state, and thus controlling the third switch Q3 to also be in the off state. At this time, the first driving terminal P3 and the second driving terminal P1 of the three-terminal fuse J are disconnected. If the current between the first connection terminal P4 and the second connection terminal P5 does not exceed a preset value, then the three-terminal fuse J is in a normal connection state. When the battery charging and discharging is abnormal, a second level can be output to the first switch Q1, controlling the first switch Q1 to be turned on, thereby controlling the second switch Q2 to be turned on, and thus controlling the third switch Q3 to also be turned on. At this time, the first driving terminal P3 of the three-terminal fuse J is connected to the second driving terminal P1. The first driving terminal P3 of the three-terminal fuse J is connected to the negative terminal of the battery. Since the first connecting terminal P4 of the three-terminal fuse J is connected to the first power supply terminal, a strong voltage can be continuously output to the three-terminal fuse J between P4 and P3, causing the three-terminal fuse J to blow within a short time. Compared with existing technologies, even in the event of voltage fluctuations or external interference, the battery protection system can actively output a control signal CON to control the three-terminal fuse J to blow and quickly cut off the power supply when it detects an abnormality in the battery state or a malfunction in the MOSFET of the charge / discharge control circuit within the system. Thus, this embodiment improves the safety of the battery protection system.

[0039] In this invention, when the battery charging and discharging are normal, the main control circuit can output a first level to the first switch Q1, controlling the first switch Q1 to be in the off state, thereby controlling the second switch Q2 to be in the off state, and thus controlling the third switch Q3 to also be in the off state. At this time, the first driving terminal P3 and the second driving terminal P1 of the three-terminal fuse J are disconnected. If the current between the first connecting terminal P4 and the second connecting terminal P5 does not exceed a preset value, then the three-terminal fuse J is in a normal connected state. When the battery charging and discharging is abnormal, a second level can be output to the first switch Q1, controlling the first switch Q1 to be turned on, thereby controlling the second switch Q2 to be turned on, and thus controlling the third switch Q3 to also be turned on. At this time, the first driving terminal P3 of the three-terminal fuse J is connected to the second driving terminal P1. The first driving terminal P3 of the three-terminal fuse J is connected to the negative terminal of the battery. Since the first connecting terminal P4 of the three-terminal fuse J is connected to the first power supply terminal, a strong voltage can be continuously output to the three-terminal fuse J between P4 and P3, causing the three-terminal fuse J to blow within a short time. Compared with existing technologies, even in the event of voltage fluctuations or external interference, the battery protection system can actively output a control signal CON to control the three-terminal fuse J to blow and quickly cut off the power supply when it detects an abnormality in the battery's state or a malfunction in the MOSFET of the charge / discharge control circuit within the system. Thus, this invention improves the safety of the battery protection system.

[0040] Please see Figure 1 In one embodiment of this utility model, the first switch Q1 is a first NMOS transistor, the second switch Q2 is a first PMOS transistor, and the third switch Q3 is a second NMOS transistor. The gate of the first NMOS transistor is connected to the first control terminal of the main control circuit, the source of the first NMOS transistor is grounded, the drain of the first NMOS transistor is connected to the gate of the first PMOS transistor, the source of the first PMOS transistor is connected to the power supply terminal of the protection circuit, the drain of the first PMOS transistor is connected to the gate of the second NMOS transistor, the drain of the second NMOS transistor is connected to the first driving terminal of the three-terminal fuse J, and the source of the second NMOS transistor and the second driving terminal of the three-terminal fuse J are connected to the negative terminal of the battery.

[0041] In this embodiment, when the battery charging and discharging are normal, the main control circuit can output a low level to the first NMOS transistor, which is then in a turned-off state. The first PMOS transistor is also in a turned-off state, as are the second NMOS transistor. At this time, the first driving terminal P3 and the second driving terminal P1 of the three-terminal fuse J are disconnected. If the current between the first connection terminal P4 and the second connection terminal P5 does not exceed a preset value, the three-terminal fuse J is in a normal connection state. When the battery charging and discharging is abnormal, such as when a severe overvoltage or overcurrent is detected, a high level can be output to the first NMOS transistor, which then conducts. The gate voltage of the first PMOS transistor is pulled low, thus conducting. The gate voltage of the second NMOS transistor is pulled high, thus conducting. At this time, the first driving terminal P3 of the three-terminal fuse J is connected to the second driving terminal P1. The first driving terminal P3 of the three-terminal fuse J is connected to the negative terminal of the battery. Since the first connecting terminal P4 of the three-terminal fuse J is connected to the first power supply terminal, a strong voltage can be continuously output to the three-terminal fuse J between P4 and P3, causing the three-terminal fuse J to blow in a short time. Thus, when the main control circuit detects an abnormality, it can output a control signal to actively control the three-terminal fuse J to blow. In this embodiment, the threshold voltage characteristics of NMOS and PMOS transistors are opposite. By using them in combination, the noise immunity of the entire circuit can be improved, making it more stable and reliable in noisy environments.

[0042] Please see Figure 1In one embodiment of this utility model, the protection circuit further includes a first resistor R1, a second resistor R2, and a third resistor R3; one end of the first resistor R1 is connected to the gate of the first NMOS transistor, and the other end of the first resistor R1 is connected to the source of the first NMOS transistor; one end of the second resistor R2 is connected to the gate of the first PMOS transistor, and the other end of the second resistor R2 is connected to the source of the first PMOS transistor; one end of the third resistor R3 is connected to the gate of the second NMOS transistor, and the other end of the third resistor R3 is connected to the source of the second NMOS transistor.

[0043] In this embodiment, connecting a series resistor between the gate and source of the MOSFET (including NMOS and PMOS) helps stabilize the gate voltage, preventing gate voltage fluctuations caused by external noise or transient interference, thereby avoiding unnecessary switching operations. Furthermore, the series resistor between the gate and source helps maintain the stability of the MOSFET's operating point, especially under temperature variations or power supply fluctuations. Thus, this embodiment improves the stability of the protection circuit.

[0044] Please see Figure 1 In one embodiment of this utility model, the protection circuit further includes a bidirectional transient voltage suppressor (TVS), one end of which is connected to the drain of the second NMOS transistor, and the other end of which is connected to the source of the second NMOS transistor.

[0045] In this embodiment, the bidirectional transient voltage suppressor (TVS) can respond quickly to voltage transients, thereby improving the stability of the protection circuit control.

[0046] Please see Figure 1 In one embodiment of this utility model, the protection circuit further includes a Zener diode DW; the negative terminal of the Zener diode DW is connected to the gate of the second NMOS transistor, and the positive terminal of the Zener diode DW is connected to the source of the second NMOS transistor.

[0047] In this embodiment, when the gate voltage of the second NMOS transistor exceeds the breakdown voltage of the Zener diode DW, it will start to conduct, thereby limiting the voltage on the gate to a certain safe value. This helps protect the gate oxide layer of the second NMOS transistor and prevents it from being damaged by overvoltage, thus improving the reliability of the control circuit of the three-terminal fuse J.

[0048] Please see Figure 1In one embodiment of this utility model, the protection circuit further includes a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, and a first capacitor C1; one end of the fourth resistor R4 is connected to the first control terminal of the main control circuit, and the other end of the fourth resistor R4 is connected to the gate of the first NMOS transistor; one end of the fifth resistor R5 is connected to the drain of the first NMOS transistor, and the other end of the fifth resistor R5 is connected to the gate of the first PMOS transistor; one end of the sixth resistor R6 and one end of the first capacitor C1 are connected to the drain of the first PMOS transistor, the other end of the sixth resistor R6 is connected to the gate of the second NMOS transistor, and the other end of the first capacitor C1 is grounded.

[0049] In this embodiment, the fourth resistor R4, the fifth resistor R5, and the sixth resistor R6 can be used for current limiting to protect the circuit safety, and the first capacitor C1 can be used for filtering to smooth the output of the first PMOS transistor.

[0050] This utility model also proposes a battery management system, which includes a first power supply terminal and a main control circuit, the main control circuit being connected to the detection terminal of the battery. The battery management system also includes a protection circuit, the specific structure of which is described in the above embodiments. Since this battery management system adopts all the technical solutions of all the above embodiments, it possesses at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be elaborated upon here.

[0051] Please refer to Figure 2 The protection circuit includes a three-terminal fuse control circuit and a three-terminal fuse J, including a first switching transistor Q1, a second switching transistor Q2, a third switching transistor Q3, and other circuit protection components (such as resistors, capacitors, Zener diodes, and bidirectional transient voltage suppressors). The three-terminal fuse control circuit is used to control the active melting of the three-terminal fuse J.

[0052] Please see Figure 2 In one embodiment of this utility model, the battery management system further includes:

[0053] Second power supply terminal;

[0054] The charging / discharging control circuit has its first terminal connected to the second power supply terminal, its second terminal connected to the first power supply terminal, its third terminal connected to the negative terminal of the battery, and its controlled terminal connected to the second control terminal of the main control circuit. The charging / discharging control circuit is used to control the charging / discharging of the battery.

[0055] The main control circuit is also used to control the operation / stop of the charge / discharge control circuit.

[0056] In this embodiment, the main control circuit can accurately grasp the state of charge of the battery by real-time monitoring and calculation of parameters such as battery voltage and current. When abnormal conditions such as overvoltage, overcurrent, or undervoltage are detected, the main control circuit can control the switching elements such as MOSFETs in the charge and discharge control circuit to turn off, quickly cutting off the charge and discharge circuit and preventing serious damage to the battery.

[0057] This utility model also proposes an energy storage component, which includes a battery and a battery management system. The specific structure of the battery management system is as described in the above embodiments. Since this battery management system adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here.

[0058] Please see Figure 2 In one embodiment of this utility model, the energy storage component further includes:

[0059] The charger has an input terminal connected to an external AC power input terminal, an output terminal connected to a second power supply terminal, and a controlled terminal connected to the main control circuit; the charger is used to convert external AC power into DC power input.

[0060] The main control circuit is also used to control the charger's operation / stop; and / or,

[0061] An inverter has its input terminal connected to the second power supply terminal, its output terminal connected to the AC power output terminal, and its controlled terminal connected to the main control circuit. The inverter is used to convert DC power to AC power output.

[0062] The main control circuit is also used to control the inverter's operation.

[0063] In this embodiment, the battery management system (BMS) works in concert with the charging / discharging equipment to provide protection. The main control circuit within the BMS communicates with the charger and / or inverter via RS-485 and CAN. When a battery malfunctions, the BMS can promptly send a signal to the charger and / or inverter. The charger and / or inverter can then take appropriate measures based on the signal, such as interrupting the output to stop the charging / discharging operation.

[0064] In summary, this embodiment achieves three levels of protection for the battery management system. In the first level of protection, the battery management system controls the operation of external charging and discharging devices such as chargers and / or inverters. When an abnormality occurs in the battery, the system controls the charger and / or inverter to take corresponding measures to stop charging and discharging. In the second level of protection, the battery management system controls switching elements such as MOSFETs in its internal charging and discharging control circuit. When an abnormality occurs in the battery and / or charging and discharging related circuits, the system quickly cuts off the charging and discharging circuit. In the third level of protection, the battery management system controls the active melting of its internal three-terminal fuse J. It should be noted that in this embodiment, the third level of protection is only activated after the first two levels of protection have been implemented. The main control circuit can actively control the melting of the three-terminal fuse J, and this melting is irreversible, increasing system reliability. Thus, in this embodiment, if an abnormal situation occurs during battery charging and discharging that prevents the charging / discharging equipment or the switching transistor of the charging / discharging control circuit from shutting down, the circuit can be quickly cut off to prevent high current from damaging the battery and other circuit components. This avoids safety issues such as overheating and fire caused by overcurrent, reducing safety hazards. In this embodiment, software methods can be used to monitor and analyze faults in the circuits within the battery management system, external charging / discharging equipment, and the battery to determine whether it is necessary to control the fuse to blow, ensuring battery safety.

[0065] The above description is merely an exemplary embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural transformations made based on the technical concept of the present utility model and the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.

Claims

1. A protection circuit applied to a battery management system, characterized in that, The battery management system includes a first power supply terminal and a main control circuit, the main control circuit being connected to the detection terminal of the battery; the protection circuit includes a first switching transistor, a second switching transistor, a third switching transistor, and a three-terminal fuse. The controlled terminal of the first switching transistor is connected to the first control terminal of the main control circuit. The first terminal of the first switching transistor is grounded. The second terminal of the first switching transistor is connected to the controlled terminal of the second switching transistor. The first terminal of the second switching transistor is connected to the power supply terminal of the protection circuit. The second terminal of the second switching transistor is connected to the controlled terminal of the third switching transistor. The first terminal of the third switching transistor is connected to the first driving terminal of the three-terminal fuse. The second terminal of the third switching transistor and the second driving terminal of the three-terminal fuse are connected to the negative terminal of the battery. The first connecting terminal of the three-terminal fuse is connected to the first power supply terminal. The second connecting terminal of the three-terminal fuse is connected to the positive terminal of the battery.

2. The protection circuit as described in claim 1, characterized in that, The first switching transistor is a first NMOS transistor, the second switching transistor is a first PMOS transistor, and the third switching transistor is a second NMOS transistor. The gate of the first NMOS transistor is connected to the first control terminal of the main control circuit, the source of the first NMOS transistor is grounded, the drain of the first NMOS transistor is connected to the gate of the first PMOS transistor, the source of the first PMOS transistor is connected to the power supply terminal of the protection circuit, the drain of the first PMOS transistor is connected to the gate of the second NMOS transistor, the drain of the second NMOS transistor is connected to the first driving terminal of the three-terminal fuse, and the source of the second NMOS transistor and the second driving terminal of the three-terminal fuse are connected to the negative terminal of the battery.

3. The protection circuit as described in claim 2, characterized in that, It also includes a first resistor, a second resistor, and a third resistor; one end of the first resistor is connected to the gate of the first NMOS transistor, and the other end of the first resistor is connected to the source of the first NMOS transistor; one end of the second resistor is connected to the gate of the first PMOS transistor, and the other end of the second resistor is connected to the source of the first PMOS transistor; one end of the third resistor is connected to the gate of the second NMOS transistor, and the other end of the third resistor is connected to the source of the second NMOS transistor.

4. The protection circuit as described in claim 2, characterized in that, It also includes a bidirectional transient voltage suppressor, one end of which is connected to the drain of the second NMOS transistor, and the other end of which is connected to the source of the second NMOS transistor.

5. The protection circuit as described in claim 2, characterized in that, It also includes a Zener diode; the negative terminal of the Zener diode is connected to the gate of the second NMOS transistor, and the positive terminal of the Zener diode is connected to the source of the second NMOS transistor.

6. The protection circuit as described in claim 2, characterized in that, It also includes a fourth resistor, a fifth resistor, a sixth resistor, and a first capacitor; one end of the fourth resistor is connected to the first control terminal of the main control circuit, and the other end of the fourth resistor is connected to the gate of the first NMOS transistor; one end of the fifth resistor is connected to the drain of the first NMOS transistor, and the other end of the fifth resistor is connected to the gate of the first PMOS transistor; one end of the sixth resistor and one end of the first capacitor are connected to the drain of the first PMOS transistor, and the other end of the sixth resistor is connected to the gate of the second NMOS transistor; the other end of the first capacitor is grounded.

7. A battery management system, characterized in that, The battery management system includes a first power supply terminal and a main control circuit, wherein the main control circuit is connected to the detection terminal of the battery; the battery management system further includes a protection circuit as described in any one of claims 1 to 6.

8. The battery management system as described in claim 7, characterized in that, Also includes: Second power supply terminal; A charge / discharge control circuit is provided, wherein a first terminal of the charge / discharge control circuit is connected to a second power supply terminal, a second terminal of the charge / discharge control circuit is connected to the first power supply terminal, a third terminal of the charge / discharge control circuit is connected to the negative terminal of the battery, and a controlled terminal of the charge / discharge control circuit is connected to a second control terminal of the main control circuit; the charge / discharge control circuit is used to control the charging / discharging of the battery. The main control circuit is also used to control the operation / stop operation of the charge / discharge control circuit.

9. An energy storage component, characterized in that, The energy storage component includes a battery and a battery management system as described in claim 8.

10. The energy storage module as described in claim 9, characterized in that, Also includes: The charger has its input terminal connected to an AC power input terminal, its output terminal connected to a second power supply terminal, and its controlled terminal connected to the main control circuit. The charger is used to convert AC power into DC power input; The main control circuit is also used to control the charger's operation / stop; and / or An inverter, wherein the input terminal of the inverter is connected to the second power supply terminal, the output terminal of the inverter is connected to the AC power output terminal, and the controlled terminal of the inverter is connected to the main control circuit; The inverter is used to convert DC power to AC power output. The main control circuit is also used to control the operation / stop operation of the inverter.

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