WO2023236451A1

WO2023236451A1 - Short-circuit protection system, and traction battery system of electric vehicle

Info

Publication number: WO2023236451A1
Application number: PCT/CN2022/133115
Authority: WO
Inventors: 刘光生; 王杭挺; 刘安龙
Original assignee: 广州小鹏汽车科技有限公司
Priority date: 2022-06-08
Filing date: 2022-11-21
Publication date: 2023-12-14
Also published as: CN114851852A

Abstract

A short-circuit protection system, and a traction battery system of an electric vehicle. The short-circuit protection system comprises: a current monitoring apparatus (110), a control module (12) and an open-circuit protection apparatus (13), wherein the current monitoring apparatus (110) is used for monitoring the current of a main loop of a circuit system to be protected, and outputting an overcurrent alarm signal when a short-circuit current is detected; the control module (12) is used for outputting, according to the overcurrent alarm signal, an open-circuit driving signal to the open-circuit protection apparatus (13) according to a set strategy; and the open-circuit protection apparatus (13) is connected in series to the main loop, and is used for being triggered, in response to a short-circuit current in the main loop and in a self-triggered manner, to enter a disconnection state, or being triggered, in response to the open-circuit driving signal and in an externally triggered manner, to enter the disconnection state, such that the main loop is disconnected.

Description

Short circuit protection system and power battery system for electric vehicles

This application claims priority to the Chinese patent application filed with the State Intellectual Property Office on June 8, 2022, with application number 2022106408945 and the application name "Short-circuit protection system and power battery system for electric vehicles", the entire content of which is incorporated by reference. incorporated in this application.

Technical field

This application relates to the technical field of power batteries, and specifically to a short-circuit protection system and a power battery system for electric vehicles.

Background technique

In order to ensure the safety of the power battery system of new energy vehicles, circuit break protection components are generally installed in the power battery system. When a short circuit occurs, the circuit break protection device can cut off the short circuit loop.

In the related art, the circuit breaker protection device is driven to perform circuit breaker protection by triggering an external controller. However, when the circuit between the external controller and the circuit breaker protection device is broken, the circuit breaker protection device cannot be triggered in time, resulting in the inability to perform circuit breaker protection on the main circuit of the battery system in time.

Contents of the invention

In order to solve or partially solve the problems existing in related technologies, this application provides a short circuit protection system and a power battery system for electric vehicles, which can improve the reliability of circuit breaker protection.

On the one hand, this application provides a short-circuit protection system, including: a current monitoring device, a control module, and a circuit breaker protection device;

The current monitoring device is used to monitor the current of the main circuit of the circuit system to be protected, and output an overcurrent alarm signal when a short-circuit current is detected;

The control module is configured to output a circuit breaker driving signal to the circuit breaker protection device according to a set strategy according to the overcurrent alarm signal;

The circuit breaker protection device is connected in series to the main circuit, and is configured to be triggered to the disconnection state in a self-triggering manner in response to the short-circuit current of the main circuit, or to be triggered to the disconnection state in an external triggering manner in response to the circuit breaker driving signal. status, causing the main circuit to be disconnected.

In one embodiment, the system further includes: a relay, connected in series to the main circuit;

The control module is also configured to: according to the overcurrent alarm signal, output a disconnection control signal to the relay according to the setting strategy, so that the relay is disconnected, so that the main circuit is disconnected.

In one embodiment, the circuit breaker protection device includes a fuse and a circuit breaker, and the fuse is connected in series with the circuit breaker;

The circuit breaker protection device being triggered to an off state in a self-triggering manner in response to the short circuit current includes:

The fuse melts and arcs in response to the short-circuit current to generate an internal drive voltage, so that the circuit breaker is triggered to an open state in response to the internal drive voltage.

In one embodiment, the circuit breaker includes a pyrotechnic circuit breaker with an igniter and a drive control circuit; the drive control circuit includes:

A rectifier bridge, connected to the igniter and connected to the control module through an external trigger interface;

A current limiting and transient suppression unit connected to the fuse through an internal drive lead;

An isolation transformer is connected between the rectifier bridge and the current limiting and transient suppression unit.

In one embodiment, the control module, according to the overcurrent alarm signal, outputs a circuit-breaking driving signal to the circuit-breaking protection device according to a set strategy, and outputs a disconnecting control signal to the relay, including:

The control module obtains the short-circuit current value according to the overcurrent alarm signal;

When the short-circuit current value does not exceed the second current threshold, the disconnection control signal is output to the relay, and when the short-circuit current value exceeds the second current threshold, the disconnection control signal is output to the relay. The circuit breaker protection device outputs the circuit breaker driving signal.

In one embodiment, when the short-circuit current value exceeds the second current threshold, the control module outputs the circuit-breaking driving signal to the circuit-breaking protection device, including:

When the short-circuit current value is less than the fifth current threshold and greater than or equal to the second current threshold, and the circuit-breaker protection device is not self-triggered within a second period of time, the control module sends a signal to the circuit-breaker protection device. The device outputs the circuit breaker driving signal.

In one embodiment, when the short-circuit current value exceeds the second current threshold, the control module outputs the circuit-breaking driving signal to the circuit-breaking protection device, and further includes:

The control module outputs the circuit breaker drive to the circuit breaker protection device when the short-circuit current value is greater than or equal to the fifth current threshold and the circuit breaker protection device is not self-triggered within the first period of time. signal, and, if the circuit breaker protection device is not triggered within a second period of time, outputting a circuit breaker driving signal to the circuit breaker protection device again; wherein the second period of time is greater than the first period of time.

The control module outputs a disconnection control signal to the relay when the circuit breaker protection device is not triggered within a third period of time, wherein the third period of time is greater than the second period of time.

In one embodiment, the current monitoring device includes a shunt and a Hall current sensor;

The overcurrent alarm signal includes a short-circuit current related value;

Wherein, if the short-circuit current monitored by the current monitoring device does not exceed the preset threshold, the short-circuit current related value is obtained based on the detection result of the Hall current sensor; if the monitored short-circuit current exceeds the preset threshold, the short-circuit current correlation value is obtained based on the detection result of the Hall current sensor. The short-circuit current correlation value is obtained from the detection result of the shunt.

In one embodiment, the current monitoring device includes a shunt and a current detection chip;

The shunt is connected in series to the main circuit and is used to output the sampling voltage;

The current detection chip is configured to output an overcurrent alarm signal including the sampling voltage value when a short-circuit current is detected based on the sampling voltage;

The control module is also used to obtain the calibrated short-circuit current value based on the pre-stored calibration parameters of the shunt and the voltage value of the sampling voltage, wherein the pre-stored calibration parameters include at least some or all of the following: initial resistance value after calibration , temperature coefficient, long-term stability parameters, thermoelectric coefficient.

In one embodiment, the system further includes:

Temperature detection sensors are provided at both ends or one end of the circuit breaker protection device and are used to output the temperature detection value of the circuit breaker protection device;

The control module is also used to send an over-temperature alarm signal when the temperature detection value reaches a set temperature threshold.

In one embodiment, the current monitoring device includes a shunt;

The shunt is configured with a first temperature output terminal group, a second temperature output terminal group, a first voltage output terminal group, and a second voltage output terminal group; wherein:

The first temperature output terminal group and the second temperature output terminal group are used to respectively output the detected temperatures on both sides of the shunt;

The first voltage output terminal group is used to output the high-speed sampling voltage value at both ends of the shunt; the second voltage output terminal group is used to output the low-speed sampling voltage value at both ends of the shunt.

In one embodiment, the control module includes a controller and a drive circuit;

The controller is connected to the current monitoring device and is configured to output a circuit breaker protection signal to the drive circuit when the overcurrent alarm signal output by the current monitoring device is detected;

The drive circuit is connected to the current monitoring device, the circuit breaker protection device and the controller, and is used to detect the overcurrent alarm signal output by the current monitoring device or detect the circuit breaker protection output by the controller. In the case of a signal, the circuit breaker driving signal is output to the circuit breaker protection device.

In one embodiment, the temperature detection sensor includes an NTC temperature detection sensor.

Another aspect of the present application provides a power battery system for an electric vehicle, including the short-circuit protection system as described in any one of the above.

The technical solution provided by this application can include the following beneficial effects:

In embodiments of the present application, when a short circuit occurs in the main circuit, the circuit breaker protection device can be triggered to the off state in a self-triggering manner in response to the short circuit current of the main circuit, or can be triggered to the off state in an external triggering manner in response to the circuit breaker drive signal of the control module. In this way, even if there is a circuit break between the control module and the circuit breaker protection device, the circuit breaker protection device can still be triggered to the disconnected state through the self-triggering method. Therefore, the effectiveness of the main circuit circuit breaker protection can be improved. reliability.

It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and do not limit the present application.

Description of the drawings

The above and other objects, features and advantages of the present application will become more apparent through a more detailed description of the exemplary embodiments of the present application in conjunction with the accompanying drawings, in which the same reference numerals generally represent Same parts.

Figure 1 is a schematic structural diagram of a short circuit protection system according to an embodiment of the present application;

Figure 2 is a schematic structural diagram of a short circuit protection system according to another embodiment of the present application;

Figure 3 is a schematic structural diagram of a short circuit protection system according to another embodiment of the present application;

Figure 4 is an enlarged view of the circuit breaker protection device of the short circuit protection system in the embodiment of Figure 3;

Figure 5 is a schematic diagram of the wiring of a shunt according to an embodiment of the present application;

Figure 6 shows the NTC temperature detection sensor in the short circuit protection system according to an embodiment of the present application;

Figure 7 is a schematic diagram of the relationship between the main circuit short-circuit current I and the self-triggering action time t of the circuit breaker protection device according to an embodiment of the present application.

Detailed ways

Embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although embodiments of the present application are shown in the drawings, it should be understood that the present application may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in this application and the appended claims, the singular forms "a," "the" and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise. It will also be understood that the term "and/or" as used herein refers to and includes any and all possible combinations of one or more of the associated listed items. It should be understood that although the terms "first", "second", "third", etc. may be used in this application to describe various information, the information should not be limited to these terms. These terms are only used to distinguish information of the same type from each other. For example, without departing from the scope of the present application, the first information may also be called second information, and similarly, the second information may also be called first information. Therefore, features defined as "first" and "second" may explicitly or implicitly include one or more of these features. In the description of this application, "plurality" means two or more than two, unless otherwise explicitly and specifically limited.

The technical solutions of the embodiments of the present application are described in detail below with reference to the accompanying drawings.

Figure 1 is a schematic structural diagram of a short circuit protection system according to an embodiment of the present application.

Referring to Figure 1, a short circuit protection system includes a current monitoring device 110, a control module 12, and a circuit breaker protection device 13.

The current monitoring device 110 is used to monitor the current of the main circuit of the circuit system to be protected, and output an overcurrent alarm signal when a short-circuit current is detected. It can be understood that in the embodiment of the present application, when the current in the main circuit is greater than a specific value (for example, the first current threshold), it can be considered that the main circuit is short-circuited. In this case, the current in the main circuit is called a short-circuit current.

The control module 12 is configured to output a circuit breaker driving signal to the circuit breaker protection device 13 according to a set strategy according to the overcurrent alarm signal.

The circuit breaker protection device 13 is connected in series to the main circuit and is used to be triggered to the off state in a self-triggering manner in response to the short-circuit current of the main circuit, or to be triggered to the off state in an external triggering manner in response to the circuit breaker driving signal output by the control module 12 , thus disconnecting the main circuit.

According to the embodiment of the present application, when a short circuit occurs in the main circuit, the circuit breaker protection device can be triggered to the off state in a self-triggering manner in response to the short-circuit current of the main circuit, or can be triggered to the off state in an external triggering manner in response to the circuit breaker driving signal of the control module. open state, thus disconnecting the main circuit. In this way, even if the circuit between the control module and the circuit breaker protection device is broken, the circuit breaker protection device can still be triggered to the off state through a self-triggering method, thus improving the reliability of the main circuit circuit breaker protection.

Figure 2 is a schematic structural diagram of a short circuit protection system according to another embodiment of the present application.

Referring to Figure 2, a short-circuit protection system includes a current monitoring device, a control module 12, a circuit breaker protection device 13, and a relay.

In one embodiment, the relay is connected in series to the main circuit 21 and is used to disconnect the main circuit 21 in response to the disconnection control signal of the control module 12 . In the example of FIG. 2 , the relays include a main positive relay 141 and a main negative relay 142 . The main positive relay 141 and the main negative relay 142 are respectively connected in series to the main circuit 21 . When the main circuit 21 of the power battery system 31 is short-circuited, the control module 12 can output a disconnection control signal to the main positive relay 141 and the main negative relay 142 according to the overcurrent alarm signal according to the set strategy, so that the main positive relay 141 and the main negative relay 142 are disconnected. The negative relay 142 is disconnected, thereby disconnecting the main circuit 21 of the power battery system 31 .

In one embodiment, the current monitoring device includes a current sensor and a current detection chip. The current sensor may include a shunt 111, for example. The shunt 111 is connected in series to the main circuit 21 and is used to output the current detection sampling voltage of the main circuit; the current detection chip is used to output an over-current alarm containing the voltage value of the sampling voltage when a short-circuit current is detected based on the sampling voltage. Signal. It can be understood that in other embodiments, the overcurrent warning signal may include other types of short-circuit current related values, or may not include short-circuit current related values. It can be understood that the current monitoring device of the present application is not limited to this. For example, in another embodiment, the current sensor includes a Hall current sensor. The Hall current sensor can be placed on the copper bar of the main circuit 21, induce the magnetic field generated by the current in the copper bar through the Hall effect, and output the current detection sample of the main circuit. Voltage.

For another example, in another embodiment, the current detection device includes a shunt 111 and a Hall current sensor. The overcurrent alarm signal output by the current monitoring device includes short-circuit current related values, such as sampling voltage values; among them, if the short-circuit current monitored by the current monitoring device does not exceed the preset threshold, the short-circuit current related value is obtained based on the detection results of the Hall current sensor. value, if the monitored short-circuit current exceeds the preset threshold, the relevant value of the short-circuit current is obtained based on the detection result of the shunt. In a specific example, if the short-circuit current of the main circuit is less than 500A, short-circuit protection control can be performed based on the detection results of the Hall current sensor. If the short-circuit current of the main circuit is greater than or equal to the set 500A, short-circuit protection control can be carried out based on the detection results of the shunt.

In one embodiment, a shunt and a Hall current sensor are used to detect the short-circuit current of the main circuit. If the short-circuit current does not exceed the preset threshold, select the detection result of the Hall current sensor for short-circuit protection control, and verify the detection result of the Hall current sensor with the detection result of the shunt; if the short-circuit current exceeds the preset threshold, select the shunt The detection results of the device are used for short circuit protection control. At the same time, a shunt and a Hall current sensor are used to detect the current of the main circuit. It is compatible with the advantages of the shunt's large current range and low accuracy and the Hall current sensor's small current range and high accuracy. Moreover, since the sampling time of the shunt is significantly faster than The sampling time of the Hall current sensor, for example, when a limit short-circuit current occurs, the short-circuit protection response speed can be improved based on the rapid detection of the shunt, thereby reducing or avoiding the adverse impact of the short-circuit current on the main circuit.

In one embodiment, the control module 12 includes a controller and a drive circuit; the controller is connected to the current monitoring device, and is used to output a circuit breaker protection signal to the drive circuit when an overcurrent alarm signal output by the current monitoring device is detected; the driver The circuit is connected to the circuit breaker protection device 13 and the controller, and is used to output a circuit breaker driving signal to the circuit breaker protection device 13 when an overcurrent alarm signal output by the current monitoring device is detected, so that the circuit breaker protection device 13 is triggered by an external triggering method. disconnected state, thus disconnecting the main circuit 21. In some embodiments, the driving circuit is also connected to the current monitoring device, and is used to output a circuit breaker driving signal to the circuit breaker protection device 13 when an overcurrent alarm signal output by the current monitoring device is detected; in this way, the current monitoring device can drive the circuit breaker. The circuit directly triggers the circuit break protection device 13, which can improve the reliability and timeliness of the circuit break protection. In one embodiment, the driving circuit may include a dedicated driving chip, but is not limited thereto.

In one embodiment, the controller obtains the short-circuit current value based on the over-current alarm signal; when the short-circuit current value does not exceed the second current threshold, outputs a disconnection control signal to the relay; and, when the short-circuit current value exceeds the second current threshold In the case of , the circuit breaker driving signal is output to the circuit breaker protection device 13 .

In one embodiment, when the short-circuit current value exceeds the second current threshold, outputting the circuit-breaking driving signal to the circuit-breaking protection device 13 includes:

When the short-circuit current value is less than the fifth current threshold and greater than or equal to the second current threshold, and the circuit breaker protection device 13 is not self-triggered within the second time period, the circuit breaker driving signal is output to the circuit breaker protection device 13 .

In one embodiment, when the short-circuit current value exceeds the second current threshold, outputting a circuit-breaking driving signal to the circuit-breaking protection device 13 also includes:

When the short-circuit current value is greater than or equal to the fifth current threshold and the circuit-breaker protection device 13 is not self-triggered within the first period of time, the circuit-breaker drive signal is output to the circuit-breaker protection device 13 , and the circuit-breaker protection device 13 is disconnected within the second period of time. 13 is not triggered, the circuit breaker driving signal is output to the circuit breaker protection device 13 again; wherein the second duration is longer than the first duration.

When the circuit breaker protection device is not triggered within a third period of time, a disconnection control signal is output to the relay, wherein the third period of time is greater than the second period of time.

In one embodiment, the circuit breaker protection device 13 includes a fuse and a circuit breaker. The fuse and the circuit breaker are connected in series; the circuit breaker can be triggered to the off state in a self-triggering mode or an external triggering mode, thereby disconnecting the main circuit. In the self-triggering mode, the fuse melts and arcs in response to the short-circuit current in the main circuit to generate an internal driving voltage, so that the circuit breaker is triggered to an open state in response to the internal driving voltage. In the external triggering mode, the circuit breaker is triggered to the off state in response to the circuit breaker drive signal from the control module.

Figure 3 is a schematic structural diagram of a short circuit protection system according to another embodiment of the present application.

Referring to FIG. 3 , the short-circuit protection system includes a shunt 111 , a high-voltage monitoring control module 12 , and a circuit breaker protection device 13 .

The high-voltage monitoring and control module 12 is connected to the circuit breaker protection device 13 and the shunt 111 respectively. The high-voltage monitoring and control module 12 includes a high-voltage part and a low-voltage part. The low-voltage part includes components such as a controller, a dedicated driver chip 123 for the circuit breaker protection device, a CAN (Controller Area Network, controller area network) transceiver 124, and peripheral circuits; the high-voltage part includes Including current detection chip 125 and peripheral circuits. The controller includes an SBC (System Basis Chip) 121 and an MCU (Microcontroller Unit) chip 122. It is understandable that the present application is not limited to this. For example, in another embodiment, the high-voltage monitoring control module 12 The controller may include a single micro control unit chip 122 or other types of control chips. The high-voltage part and the low-voltage part are isolated from each other by an isolation power chip 126 and a signal isolation chip 127 . The external interface of the low-voltage part includes a power signal interface, a CAN signal interface, a wake-up signal interface, a collision signal interface, a Hall current sensor signal interface, and a drive signal interface of the circuit breaker protection device 13 . The external interface of the high-voltage part includes a temperature acquisition signal interface, a voltage acquisition signal interface, and a high-voltage loop reference ground signal interface for the shunt 111. The shunt 111 is connected in series to the main circuit 21 and is used to output the current detection sampling voltage of the main circuit. When the current detection chip 125 detects a short-circuit current based on the sampling voltage, it can use the overcurrent alarm signal to directly drive the dedicated driver chip 123 through the hardware circuit to trigger the circuit breaker protection device 13 . The current detection chip 125 can also send the overcurrent alarm signal to the MCU chip 122; the MCU chip 122 triggers the circuit breaker protection device 13 through the dedicated drive chip 123 according to the set strategy based on the short-circuit current related value contained in the overcurrent alarm signal. .

FIG. 4 is an enlarged view of the circuit breaker protection device of the short circuit protection system of the embodiment of FIG. 3 .

Referring to Figures 3 and 4 together, in one embodiment, the circuit breaker protection device 13 includes a thermal fuse 131, a pyrotechnic circuit breaker 132 with an igniter, and a drive control board 133; the drive control circuit on the drive control board 133 includes a rectifier bridge. , current limiting and transient suppression unit, isolation transformer.

The main circuit of the pyrotechnic breaker 132 is connected in series with the thermal fuse 131 , and the pyrotechnic breaker 132 and the thermal fuse 131 are respectively connected in series in the main circuit 21 of the battery system 31 . The internal drive interface of the drive control board 133 is connected in parallel to both ends of the thermal fuse 131 through multiple internal drive leads, and the igniter drive interface of the drive control board 133 is connected to the igniter of the pyrotechnic circuit breaker 132 through lines. The external trigger interface of the drive control board 133 is connected to the dedicated drive chip 123 and is connected to the ignition drive interface of the pyrotechnic circuit breaker 132 through the rectifier bridge. The internal drive interface of the drive control board 133 is connected to the isolation unit through the current limiting and transient suppression unit. The primary side of the transformer and the secondary side of the isolation transformer are connected to the igniter drive interface of the pyrotechnic circuit breaker 132 through the rectifier bridge.

There are two triggering methods of the circuit breaker protection device 13 . The first method is external triggering. The igniter of the pyrotechnic circuit breaker 132 is triggered by the circuit breaker driving signal output by the dedicated driving chip 123; for example, the dedicated driving chip 123 outputs a driving current (for example, about 2A), and the driving current is input through the external trigger interface 134. The igniter of the pyrotechnic circuit breaker 132 is triggered after rectification by the rectifier bridge. The igniter pushes the push rod to cut off the main circuit of the pyrotechnic circuit breaker 132, so that the circuit breaker protection device 13 is triggered to the disconnected state; the second method is self-triggering, and the pyrotechnic circuit breaker 132 The igniter is triggered by the internal driving voltage generated by the melting and arcing of the thermal fuse 131. For example, when the main circuit 21 of the battery system 31 is short-circuited, the short-circuit current causes the thermal fuse 131 to melt and arc to generate an internal driving voltage, which generates a current in the internal driving lead, and the current passes through the current limiting and transient suppression unit and the isolation transformer. After rectification by the rectifier bridge, the igniter of the pyrotechnic circuit breaker 132 is triggered. The igniter pushes the push rod to cut off the main circuit of the pyrotechnic circuit breaker 132, causing the circuit breaker protection device 13 to be triggered to the disconnected state, thus disconnecting the main circuit 21 of the battery system 31. . Among them, the resistance value or breakdown voltage of the current limiting and transient suppression unit can be adjusted to set the self-triggering condition of the circuit breaker protection device 13 .

In one embodiment, the dedicated driver chip 123 also outputs a detection current (for example, 100 mA) to the circuit breaker protection device 13 for monitoring the status of the igniter of the pyrotechnic circuit breaker 132 and the integrity of the drive circuit of the circuit breaker protection device 13 . The state of the igniter includes the normal state of the gunpowder (for example, corresponding to the situation where the resistance is in the range of 1.7Ω to 2.3Ω), the state of the gunpowder failure (for example, corresponding to the situation where the resistance is <1.7Ω or the resistance is >2.3Ω); the circuit breaker protection device 13 drives The status of the circuit includes short circuit and open circuit. When the gunpowder of the igniter fails, or a short circuit or open circuit occurs in the drive circuit of the circuit breaker protection device 13, the controller can output a corresponding prompt signal.

Figure 5 is a schematic diagram of the wiring of a shunt according to an embodiment of the present application.

In this embodiment, the shunt 111 is configured with a first temperature output terminal group, a second temperature output terminal group, a first voltage output terminal group, and a second voltage output terminal group; wherein: the first temperature output terminal group and the second temperature output terminal group The output terminal group is used to output the detected temperatures on both sides of the shunt 111 respectively; the first voltage output terminal group is used to output the high-speed sampling voltage at both ends of the shunt 111; the second voltage output terminal group is used to output the low-speed sampling voltage at both ends of the shunt. . Referring to Figure 5, the current detection chip 125 of the control module is connected to the shunt 111 through multiple pins (Pin), wherein the pin Pin1 and the pin Pin2 are connected to the first temperature output terminal group at one end of the shunt 111 for Obtain the temperature at one end of the shunt 111; pins Pin8 and Pin9 are connected to the second temperature output terminal group at the other end of the shunt 111 for obtaining the temperature at the other end of the shunt 111; pins Pin4 and Pin5 are connected to The first voltage output terminal group at both ends of the alloy of the shunt 111 is used to obtain the sampling voltage at both ends of the alloy of the shunt 111. Pins Pin3 and Pin6 are connected to the second voltage output terminal group at both ends of the alloy of the shunt 111. In order to obtain the redundant sampling voltage at both ends of the shunt 111 alloy, pin 7 is used to measure the high-voltage loop reference ground. In one embodiment, one of the first voltage output terminal group and the second voltage output terminal group outputs a high-speed sampling voltage, and the other group outputs a low-speed sampling voltage. By configuring two channels of voltage sampling, the short-circuit current of the main circuit can be more accurately detected and the measurement error of the shunt 111 can be reduced; by configuring two channels of temperature sampling, the error of the thermoelectric coefficient of the shunt 111 can be better calibrated.

In one embodiment, NTC (Negative Temperature Coefficient, negative temperature coefficient) thermistors can be respectively set at both ends of the shunt 111 to detect the temperatures at both ends of the shunt 111 respectively. The first temperature output terminal group and the second temperature output terminal group of the shunt 111 are respectively connected to corresponding NTC thermistors. The current detection chip 125 is connected to the first temperature output terminal group through the pin Pin1 and the pin Pin2 and the third temperature output terminal group. The pins Pin8 and Pin9 connected to the two temperature output terminal groups obtain the temperature detection signals at both ends of the shunt 111 .

The short-circuit protection system in another embodiment of the present application also includes a temperature detection sensor. The temperature detection sensor is arranged at both ends of the circuit breaker protection device 13 and is used to output the temperature detection value of the circuit breaker protection device 13; the control module 12 is also used to detect the temperature of the circuit breaker protection device 13. When the temperature detection value of the detection sensor reaches the set temperature threshold, an over-temperature alarm signal is issued.

Figure 6 shows the NTC temperature detection sensor in the short circuit protection system according to an embodiment of the present application.

Referring to Figure 6, in a specific example, NTC temperature detection sensors 151 are provided at both ends of the circuit breaker protection device 13 for detecting the temperature of the circuit breaker protection device 13; when the control module 12 monitors that the temperature of the circuit breaker protection device 13 reaches 130°C , sending out a first-level over-temperature alarm signal; when the temperature reaches 140 degrees Celsius, a second-level over-temperature alarm signal is sent out. It can be understood that in another embodiment, only one temperature detection sensor may be provided.

During use, the shunt 111 will generate power loss and dissipate it as heat. In order to reduce the power loss of the shunt 111, the resistance of the shunt 111 can be reduced. If the resistance of the shunt 111 is too low, it will result in a too low sampling signal voltage and a high manufacturing cost of the shunt 111. The sampling signal voltage can be processed by a programmable gain operational amplifier, but the manufacturing cost is high. One solution is to reduce the manufacturing cost by reducing the accuracy of the shunt 111, but the reduction in the accuracy of the shunt 111 makes it impossible to measure accurately. Therefore, the reduced-precision shunt 111 needs to be calibrated to improve the measurement accuracy of the shunt 111. . For example, a current of 500A is suitable for a 50uΩ shunt. To manufacture a 50uΩ shunt with an accuracy of 1%, it is necessary to control the resistance of the shunt to 49.5-50.5uΩ, which is quite difficult and directly leads to high manufacturing costs. In an embodiment of the present application, the accuracy of the shunt can be reduced, for example, controlled within 5%, and the shunt is calibrated and compensated. Through the calibration compensation of the shunt, the impact of the reduction in the accuracy of the shunt on the measurement is reduced.

In one embodiment, the calibration of the shunt 111 includes the calibration of the initial resistance value, the calibration of the temperature coefficient, the calibration of the long-term stability parameters, and the calibration of the thermoelectric coefficient. After the shunt 111 and the control module 12 are combined, the initial resistance, temperature coefficient, long-term stability parameter, thermoelectric coefficient of the shunt 111 and the operational amplifier gain coefficient and offset of the control module 12 are calibrated, and the initial value obtained by the calibration is The resistance, temperature coefficient, long-term stability parameters, thermoelectric coefficient, op amp gain coefficient, and offset are marked with two microcodes, and the calibrated parameters are written into the MCU chip 122.

Calibration of the initial resistance of the shunt: The nominal initial resistance of the shunt when it leaves the factory usually has a certain error compared with the true value. According to the embodiment of the present application, in the final section of the shunt production line, the real initial resistance value R _shunt of the shunt is obtained through actual measurement. In the construction of the controller software architecture, it is reserved to write the real initial resistance value through the bus. program, so that the true initial resistance R _{shunt of the} shunt is pre-stored in the controller, for example, in the E2PROM (Electrically Erasable Programmable Read Only Memory) of the MCU chip.

Calibration of the long-term stability parameter R _LTS of the shunt: The long-term stability parameter R _LTS of the shunt refers to the rate of change of the resistance of the shunt relative to time. It is generally tested in a high-temperature (such as 140°C) test environment for thousands of hours. Derived later. Whether the long-term stability parameter R _LTS of the shunt needs to be compensated will be decided after the shunt has been running for a period of time and verified. For example, when applied to vehicles, the long-term stability parameter LTS of the shunt pre-stored in the MCU chip E2PROM can be compensated through the vehicle's later OTA (Over The Air Technology, over-the-air upgrade).

Calibration of the thermoelectric coefficient EMF of the shunt: The metal terminal and the alloy terminal of the shunt are two different electrical conductors. When there is a temperature difference, a potential difference will occur between the two different electrical conductors, and the potential difference will be superimposed to the actual collected voltage, leading to measurement errors. For the calibration of the thermoelectric coefficient EMF of the shunt, a set number of shunts from the same batch as the shunt can be sampled and measured to obtain the average thermoelectric coefficient EMF of the set number of shunts. The average thermoelectric coefficient EMF can be used for the shunt. The thermoelectric coefficient EMF of the shunt (for example, the thermoelectric coefficient EMF of the shunt is less than 1uV/℃), and the thermoelectric coefficient EMF of the shunt is pre-stored in the E2PROM of the MCU chip.

Calibration of the shunt temperature coefficient TCR: The temperature coefficient TCR refers to the proportion of the shunt resistance that changes with temperature. The temperature coefficient is nonlinear. Therefore, it is necessary to select a shunt with a TCR as low as possible to reduce the difficulty of later calibration. The data reference for this parameter must be clearly defined as the TCR of the entire shunt. The temperature drift distribution curve of the same batch of shunts is analyzed using a regression analysis method to obtain the formula of the temperature drift distribution curve, that is, the change formula of the resistance drift of the shunt relative to the temperature value. This formula must be at least a cubic function (regression parabola). More accurately describes the temperature drift curve changes. The cubic function has 4 coefficients. In theory, at least 4 measurement points can meet the requirements. An additional temperature measurement point is added for closed-loop detection.

After obtaining the temperature drift curve of the shunt, the compensation value for each degree Celsius can be obtained through special software. This compensation value can integrate the initial accuracy error and be pre-stored in the E2PROM of the MCU chip through the bus through a lookup table to improve the accuracy of the shunt resistance. Compensation efficiency.

The formula of the temperature drift curve is T _TCR = aT ³ + bT ² + cT + d. In an example, as shown in Table 1, the initial value of the shunt temperature coefficient TCR is 1 (20℃ ~ 30℃), from -40℃ ~ 150 ℃, set the T _TCR value with a gradient of 10°C. The T _TCR is obtained by looking up the table based on the average value of the two temperatures of the shunt:

Table 1:

温度范围/℃Temperature range/°C	-40～-30-40～-30	-30～-20-30～-20	………	20～3020～30	30～4030～40	………	130～140130～140	140～150140～150
T _TCR T _TCR	T _TCR1 T _TCR1	T _TCR2 T _TCR2	………	11	T _TCR8 T _TCR8	………	T _TCR18 T _TCR18	T _TCR19 T _TCR19

The values of R _shunt , T _TCR , EMF and R _LTC in the initial software of the controller are empty. Write R _shunt , T _TCR , EMF and R _LTC into the MCU chip through the host computer. After R _shunt , T _TCR , EMF, and R _LTC are written into the MCU chip, the controller's op amp gain coefficient k and offset b are calibrated.

The calibration of the controller's operational amplifier gain coefficient k and offset b can be completed by actual measurement and calibration of the matching shunt on the production line. The sampling range is calibrated in sections. The current calibration interval is exemplarily set as shown in Table 2:

Table 2:

As shown in Table 2, at least 3 current values are extracted in each current calibration interval, and the current values obtained by the controller are calibrated through digital high-precision current detection equipment, that is, the operational amplifier gain coefficient k and offset of the controller are calibrated. Calibration of quantity b. Each interval has an independent k value and an independent b value. The initial k value is 1 and the initial b value is 0. The calibrated k value and the calibrated b value are obtained by linear fitting of at least three current values in each current calibration interval. k and b are calibrated by comparing the current value measured by the digital high-precision current sensing device with the current value obtained by the controller. Write the calibrated k value and calibrated b value into the MCU chip through the host computer. Complete the calibration of the k value and b value of each current calibration interval in sequence. Then set multiple sets of corresponding positive and negative current values, and use digital high-precision current detection equipment to check the current values obtained by the calibrated controller. The current values set during the inspection are different from the current values set during the calibration. .

In one embodiment, the control module 12 obtains the voltage value of the sampling voltage of the shunt 111, and obtains the calibrated short-circuit current value according to the pre-stored calibration parameters of the shunt 111 and the voltage value of the sampling voltage, wherein the pre-stored calibration parameters at least include the following parts or All: Calibrated initial resistance, temperature coefficient, long-term stability parameters, thermoelectric coefficient of shunt 111.

In one embodiment, the control module 12 obtains the calibrated short-circuit current value I according to the following formula:

Among them, V _measure is the voltage value of the sampling voltage of the shunt 111; R _shunt is the calibrated initial resistance value of the shunt 111; V _EMF is the thermoelectric voltage of the shunt 111. During discharge, V _EMF = EMF × (T ₁ -T ₂ ), V _EMF = EMF × (T ₂ -T ₁ ) during charging; T _TCR is the temperature coefficient of the shunt 111, T _TCR = aT ³ + bT ² + cT + d,

T _TCR can be obtained by looking up the table according to Table 1; L _LTS is the long-term stability coefficient of the shunt 111,

k is the gain coefficient of the operational amplifier; b is the offset amount; T ₁ is the temperature value collected by the temperature detection sensor at one end of the shunt 111; T ₂ is the temperature value collected by the temperature detection sensor at the other end of the shunt 111; EMF is the thermoelectric value of the shunt 111 Coefficient; R _LTC is the resistance value of the shunt 111 after working for a long time.

Combined with the short-circuit protection system of the above embodiment, the short-circuit protection strategy of one embodiment of the present application is described as follows. It can be understood that the present application is not limited to this.

Referring to FIG. 2 , when the control module 12 determines that the current in the main circuit is less than the first current threshold (I0) and receives a high-voltage cutoff instruction from the BMS (Battery Management System) of the battery system 31 , for example, Then the main positive relay 141 and the main negative relay 142 are controlled to disconnect the main circuit, and the relays are used for short-circuit protection; when the control module 12 determines that the current in the main circuit is less than the first current threshold (I0), and no high-voltage interruption instruction is received, Then the current of the main circuit 21 is regarded as the normal operating current and no processing is performed.

In one embodiment, when the control module 12 determines that the current in the main circuit 21 is greater than or equal to the first current threshold (I0) and less than the second current threshold (I1), it delays for a third time (t3) and controls the main circuit. The positive relay 141 and the main negative relay 142 disconnect the main circuit 21, and the relay is used for short circuit protection.

In one example, the second current threshold is a critical value of current at which the relay can switch between normal on and off.

In one embodiment, when the control module 12 determines that the current in the main circuit 21 is greater than or equal to the second current threshold (I1) and less than the third current threshold (I2), it delays the second time period (t2) and drives the circuit breaker protection. device 13, so that the circuit breaker protection device 13 is externally triggered to disconnect the main circuit 21, and the external trigger circuit breaker protection device 13 is used for short circuit protection.

If the circuit breaker protection device 13 is not triggered externally, the control module 12 detects that the circuit breaker protection device 13 is in a non-triggered state within the third period of time (t3), controls the main positive relay 141 and the main negative relay 142 to disconnect the main circuit 21, and uses relays to perform the operation. Short circuit protection, relay cuts off with load. After the relay is disconnected within this short-circuit current range, a voltage potential will be formed between the relay contacts, so that the electric energy required to melt the thermal fuse 131 will not be sufficient, so the circuit-breaker protection device 13 does not have self-triggering short-circuit protection capability.

In one embodiment, when the control module 12 determines that the current in the main circuit 21 is greater than or equal to the third current threshold (I2) and less than the fourth current threshold (I3), it delays the second time period (t2) and drives the circuit breaker protection. device 13, so that the circuit breaker protection device 13 is externally triggered to disconnect the main circuit 21, and the external trigger circuit breaker protection device 13 is used for short circuit protection.

If the external triggering of the circuit breaker protection device 13 does not operate, within the third time period (t3), the thermal fuse 131 melts and the circuit breaker protection device 13 disconnects the main circuit 21, and the circuit breaker protection device 13 performs self-triggered short circuit protection. In one example, the third current threshold is the corresponding short-circuit current value when the thermal fuse blows and the protection time of the self-triggered circuit breaker protection device is equal to the third duration, so that the circuit breaker protection device can be self-triggered within the third duration (t3).

If neither the external triggering nor the self-triggering of the circuit breaker protection device 13 operates, and the control module 12 detects that the circuit breaker protection device 13 is in a non-triggered state within the third period of time (t3), it controls the main positive relay 141 and the main negative relay 142 to disconnect the main circuit. , using a relay for short circuit protection, and the relay cuts off with load.

In one embodiment, when the control module 12 determines that the current in the main circuit 21 is greater than or equal to the fourth current threshold (I3) and less than the fifth current threshold (I4), the thermal fuse 131 is blown and the self-triggered circuit breaker protection device 13 is triggered early. After the second delay time (t2) of the controller, the main circuit 21 is triggered to disconnect, and the circuit breaker protection device 13 performs self-triggered short-circuit protection. In one example, the fourth current threshold is the corresponding short-circuit current value when the thermal fuse blows and the protection time of the self-triggered circuit breaker protection device is equal to the second duration, so that the circuit breaker protection device can be self-triggered within the second duration.

If the circuit breaker protection device 13 is not triggered by itself and the control module 12 detects that the circuit breaker protection device 13 is in a non-triggered state within the second time period (t2), it drives the circuit breaker protection device 13 so that the circuit breaker protection device 13 is externally triggered to disconnect the main circuit. 21. Use externally triggered circuit breaker protection device 13 for short circuit protection.

If neither the external triggering nor the self-triggering of the circuit breaker protection device 13 operates, and the control module 12 detects that the circuit breaker protection device 13 is in a non-triggered state within the second time period (t2), it controls the main positive relay 141 and the main negative relay 142 to disconnect the main circuit. , using a relay for short circuit protection, and the relay cuts off with load.

In one embodiment, when the control module 12 determines that the current in the main circuit is greater than or equal to the fifth current threshold (I4) and less than the sixth current threshold (I5), the control module 12 delays for a first time period (t1) and drives The circuit breaker protection device 13 is externally triggered to disconnect the main circuit 21, and the external trigger circuit breaker protection device 13 is used for short circuit protection.

If the self-triggered circuit breaker protection device 13 does not operate, the thermal fuse 131 melts and the self-triggered circuit breaker protection device 13 is externally triggered to disconnect the main circuit 21 earlier than the control module 12 delays t2, and the circuit breaker protection device 13 performs self-triggered short-circuit protection.

If the circuit breaker protection device 13 is neither self-triggered nor externally triggered, and the control module 12 detects that the circuit breaker protection device 13 is in a non-triggered state within the second time period (t2), it drives the circuit breaker protection device 13 so that the circuit breaker protection device 13 is externally triggered. The main circuit 21 is disconnected and an externally triggered circuit breaker protection device 13 is used for short circuit protection.

If the circuit breaker protection device 13 does not operate due to self-triggering or two external triggers, and the control module 12 detects that the circuit breaker protection device 13 is in a non-triggered state within the third period of time (t3), it controls the main positive relay 141 and the main negative relay 142 to disconnect. The main circuit 21 uses a relay for short-circuit protection, and the relay cuts off with load.

In one embodiment, when the control module 12 determines that the current in the main circuit 21 is greater than or equal to the sixth current threshold (I5), the thermal fuse 131 is blown and the self-triggered circuit breaker protection device 13 is triggered earlier than the control module 12 after the delay time t1. The main circuit 21 is opened, and the circuit breaker protection device 13 performs self-triggering short-circuit protection. In one embodiment, the sixth current threshold is the corresponding short-circuit current value when the thermal fuse blows and the protection time of the self-triggered circuit breaker protection device is equal to the first duration, so that the circuit breaker protection device can be self-triggered within the first duration.

If the circuit breaker protection device 13 is not triggered by itself and the control module 12 detects that the circuit breaker protection device 13 is in a non-triggered state within the first period of time (t1), it drives the circuit breaker protection device 13 so that the circuit breaker protection device 13 is externally triggered to disconnect the main circuit. 21. Use externally triggered circuit breaker protection device 13 for short circuit protection.

If the circuit breaker protection device 13 does not operate due to self-triggering or two external triggers, and the control module 12 detects that the circuit breaker protection device 13 is in a non-triggered state within the third period of time (t3), it controls the main positive relay 141 and the main negative relay 142 to disconnect. The main circuit adopts relay for short-circuit protection, and the relay cuts off with load.

In one embodiment, the first duration is shorter than the second duration, and the second duration is shorter than the third duration.

In a specific example, the first current threshold is 1000A, the second current threshold is 1500A, the third current threshold is 4300A, the fourth current threshold is 4700A, the fifth current threshold is 6000A, the sixth current threshold is 7500A, and the first duration t1 is 5ms, the second duration t2 is 100ms, and the third duration t3 is 200ms. It can be understood that the present application is not limited to this.

According to the technical solution shown in the embodiment of this application, when a short circuit occurs in the main circuit, the control module can promptly drive the circuit breaker protection device according to the current signal of the main circuit, so that the circuit breaker protection device disconnects the main circuit in time to protect the main circuit. For example, based on the rapid detection results of the shunt, the control module can drive the circuit breaker protection device to trigger an external trigger to disconnect the main circuit in a very short time (for example, the first delay time is 5ms), so that when a large current short circuit occurs, the control module can quickly Protect the main circuit.

Furthermore, according to the technical solution shown in the embodiment of the present application, when a short circuit occurs in the main circuit, the circuit breaker protection device is automatically triggered or externally triggered to disconnect the main circuit according to the short circuit current of the main circuit, so that the circuit breaker protection device can perform timely maintenance on the main circuit. Protection, and within the set time period, if the circuit breaker protection device does not disconnect the main circuit due to self-triggering or external triggering, the relay can be driven in time so that the relay disconnects the main circuit, and the relay can be used to protect the main circuit in time.

Referring to Figure 7, curve 71 in the figure represents the relationship between the main circuit short-circuit current I (kA) and the self-triggering action time t (s) of the circuit breaker protection device 13. When the short-circuit current is greater than I5 (7500A), the circuit-breaker protection device 13 can self-trigger within time t1 (5ms); when the short-circuit current is I3 (4700A) ~ I5 (7500A), the circuit-breaker protection device 13 can trigger at time t2 (100ms). It can self-trigger within time t3 (200ms) when the short-circuit current is I2 (4300A) ~ I3 (4700).

According to another embodiment of the present application, the present application also provides a power battery system for an electric vehicle, which has the short-circuit protection system as described above. Electric vehicles may be, for example, electric cars, electric aircraft, etc.

The embodiments of the present application have been described above. The above description is illustrative, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical applications, or improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

A short-circuit protection system, characterized by including: a current monitoring device, a control module, and a circuit breaker protection device;

The current monitoring device is used to monitor the current of the main circuit of the circuit system to be protected, and output an overcurrent alarm signal when a short-circuit current is detected;

The control module is configured to output a circuit breaker driving signal to the circuit breaker protection device according to a set strategy according to the overcurrent alarm signal;

The circuit breaker protection device is connected in series to the main circuit, and is configured to be triggered to the disconnection state in a self-triggering manner in response to the short-circuit current of the main circuit, or to be triggered to the disconnection state in an external triggering manner in response to the circuit breaker driving signal. status, causing the main circuit to be disconnected.
The system according to claim 1, characterized in that:

The system also includes: a relay, connected in series to the main circuit;

The control module is also configured to: according to the overcurrent alarm signal, output a disconnection control signal to the relay according to the setting strategy, so that the relay is disconnected, so that the main circuit is disconnected.
The system according to claim 1, characterized in that:

The circuit breaker protection device includes a fuse and a circuit breaker, and the fuse is connected in series with the circuit breaker;

The circuit breaker protection device being triggered to an off state in a self-triggering manner in response to the short circuit current includes:

The fuse melts and arcs in response to the short-circuit current to generate an internal drive voltage, so that the circuit breaker is triggered to an open state in response to the internal drive voltage.
The system according to claim 3, wherein the circuit breaker includes a pyrotechnic circuit breaker with an igniter and a drive control circuit; the drive control circuit includes:

A rectifier bridge, connected to the igniter and connected to the control module through an external trigger interface;

A current limiting and transient suppression unit connected to the fuse through an internal drive lead;

An isolation transformer is connected between the rectifier bridge and the current limiting and transient suppression unit.
The system according to claim 2, characterized in that:

The control module, according to the overcurrent alarm signal, outputs a circuit breaker driving signal to the circuit breaker protection device according to a set strategy, and outputs a disconnection control signal to the relay, including:

The control module obtains the short-circuit current value according to the overcurrent alarm signal;

When the short-circuit current value does not exceed the second current threshold, the disconnection control signal is output to the relay, and when the short-circuit current value exceeds the second current threshold, the disconnection control signal is output to the relay. The circuit breaker protection device outputs the circuit breaker driving signal.
The system according to claim 5, characterized in that: when the short-circuit current value exceeds the second current threshold, the control module outputs the circuit-breaking driving signal to the circuit-breaking protection device, including:

When the short-circuit current value is less than the fifth current threshold and greater than or equal to the second current threshold, and the circuit-breaker protection device is not self-triggered within a second period of time, the control module sends a signal to the circuit-breaker protection device. The device outputs the circuit breaker driving signal.
The system according to claim 6, wherein the control module outputs the circuit-breaking driving signal to the circuit-breaking protection device when the short-circuit current value exceeds the second current threshold, and further includes:

The control module outputs the circuit breaker drive to the circuit breaker protection device when the short-circuit current value is greater than or equal to the fifth current threshold and the circuit breaker protection device is not self-triggered within the first period of time. signal, and, if the circuit breaker protection device is not triggered within a second period of time, outputting a circuit breaker driving signal to the circuit breaker protection device again; wherein the second period of time is greater than the first period of time.
The system according to claim 6 or 7, characterized in that: when the short-circuit current value exceeds the second current threshold, the control module outputs the circuit-breaking driving signal to the circuit-breaking protection device, and further include:

The control module outputs a disconnection control signal to the relay when the circuit breaker protection device is not triggered within a third period of time, wherein the third period of time is greater than the second period of time.
The system according to claim 1, characterized in that:

The current monitoring device includes a shunt and a Hall current sensor;

The overcurrent alarm signal includes a short-circuit current related value;

Wherein, if the short-circuit current monitored by the current monitoring device does not exceed the preset threshold, the short-circuit current related value is obtained based on the detection result of the Hall current sensor; if the monitored short-circuit current exceeds the preset threshold, the short-circuit current correlation value is obtained based on the detection result of the Hall current sensor. The short-circuit current correlation value is obtained from the detection result of the shunt.
The system according to claim 1, characterized in that:

The current monitoring device includes a shunt and a current detection chip;

The shunt is connected in series to the main circuit and is used to output the sampling voltage;

The current detection chip is configured to output an overcurrent alarm signal including the sampling voltage value when a short-circuit current is detected based on the sampling voltage;

The control module is also used to obtain the calibrated short-circuit current value based on the pre-stored calibration parameters of the shunt and the voltage value of the sampling voltage, wherein the pre-stored calibration parameters include at least some or all of the following: initial resistance value after calibration , temperature coefficient, long-term stability parameters, thermoelectric coefficient.
The system of claim 1, further comprising:

Temperature detection sensors are provided at both ends or one end of the circuit breaker protection device and are used to output the temperature detection value of the circuit breaker protection device;

The control module is also used to send an over-temperature alarm signal when the temperature detection value reaches a set temperature threshold.
The system according to claim 1, characterized in that:

The current monitoring device includes a shunt;

The shunt is configured with a first temperature output terminal group, a second temperature output terminal group, a first voltage output terminal group, and a second voltage output terminal group; wherein:

The first temperature output terminal group and the second temperature output terminal group are used to respectively output the detected temperatures on both sides of the shunt;

The first voltage output terminal group is used to output the high-speed sampling voltage value at both ends of the shunt; the second voltage output terminal group is used to output the low-speed sampling voltage value at both ends of the shunt.
The system according to claim 1, wherein the control module includes a controller and a drive circuit;

The controller is connected to the current monitoring device and is configured to output a circuit breaker protection signal to the drive circuit when the overcurrent alarm signal output by the current monitoring device is detected;

The drive circuit is connected to the current monitoring device, the circuit breaker protection device and the controller, and is used to detect the overcurrent alarm signal output by the current monitoring device or detect the circuit breaker protection output by the controller. In the case of a signal, the circuit breaker driving signal is output to the circuit breaker protection device.
The system according to claim 11, characterized in that:

The temperature detection sensor includes an NTC temperature detection sensor.
A power battery system for an electric vehicle, characterized by including the short-circuit protection system according to any one of claims 1-14.