CN114792965A - Battery protection system, battery protection method and vehicle - Google Patents

Abstract

The present disclosure relates to a battery protection system, a battery protection method, and a vehicle. The disclosed battery protection system includes: a fuse disposed on a main circuit of the battery; the contactor is arranged on a charging circuit and/or a discharging circuit of the battery; a circuit breaker disposed on a main circuit of the battery; current detection means for detecting a battery current flowing through the battery; and the controller is in communication connection with the current detection device and the circuit breaker and is used for controlling the circuit breaker to be opened to cut off the main loop under the condition that the battery current is greater than or equal to the maximum allowable current of the contactor. So, when battery current exceeded the maximum allowable current of contactor, can in time cut off the major loop through the circuit breaker, the circuit breaker response is rapid, can effectively protect the major loop, covers the blind area that contactor and fuse can't protect, reduces the battery because of the too big possibility that leads to the high temperature or even the explosion on fire of electric current.

Description

Battery protection system, battery protection method and vehicle

technical field

The present disclosure relates to the field of vehicles, and in particular, to a battery protection system, a battery protection method, and a vehicle.

Background technique

With the development of new energy vehicle technology, more and more attention has been paid to the safety requirements of vehicles. In the current market, vehicle fires occur frequently. The causes of fires include current overload, short circuit, collision, battery and other problems.

In order to solve the situation of excessive current caused by overload, short circuit or collision on the circuit where the battery is located, a contactor and a fuse are generally set in the circuit to cut off the circuit when the current is too large.

However, since the maximum allowable passing current of the contactor is less than the fusing current of the fuse, there is a protection blind zone in the battery circuit where the contactor and the fuse are set, which neither the contactor nor the fuse can cover. When the overload current is located in the protection blind zone When the battery is inside, the contactor cannot operate and the fuse cannot be blown, which may easily cause the battery temperature to be too high or even catch fire.

SUMMARY OF THE INVENTION

The purpose of the present disclosure is to provide a battery protection system, a battery protection method and a vehicle to eliminate the blind spot of current overload protection.

In order to achieve the above object, a first aspect of the present disclosure provides a battery protection system, comprising: a fuse, provided on a main circuit of the battery; a contactor, provided on a charging circuit and/or a discharging circuit of the battery; a circuit breaker, arranged on the main circuit of the battery; a current detection device, used to detect the battery current flowing through the battery; a controller, connected in communication with the current detection device and the circuit breaker, used for When the battery current is greater than or equal to the maximum allowable current of the contactor, the circuit breaker is controlled to be disconnected to cut off the main circuit.

Optionally, the circuit breaker is also connected in direct communication with a crash sensor, for automatically disconnecting in response to a crash signal generated by the crash sensor.

Optionally, the controller is configured to control the circuit breaker to open to cut off when the battery current is greater than or equal to the maximum allowable current of the contactor and less than or equal to the fusing current of the fuse the main circuit.

Optionally, the controller is also connected in communication with the contactor, for controlling the contactor when the battery current is greater than or equal to a preset current threshold and less than the maximum allowable current of the contactor. Contactor is open.

Optionally, the contactor includes a first contactor disposed on the charging circuit, and the controller is configured to, when the battery is in the charging mode, when the battery current is greater than or equal to a preset current threshold, When the current is less than the maximum allowable current of the first contactor, the first contactor is controlled to be disconnected.

Optionally, the contactor includes a second contactor disposed on the discharge circuit, and the controller is configured to, when the battery is in the discharge mode, when the battery current is greater than or equal to a preset current threshold, When the current is less than the maximum allowable current of the second contactor, the second contactor is controlled to be disconnected.

Optionally, the controller is one of the following: a battery management system, a domain controller, and a vehicle controller.

A second aspect of the present disclosure provides a battery protection method, comprising: detecting a battery current flowing through the battery; when the battery current is greater than or equal to a contactor disposed on a charging circuit and/or a discharging circuit of the battery In the case of the maximum allowable current, the circuit breaker provided on the main circuit of the battery is controlled to open to cut off the main circuit.

Optionally, the method further includes: controlling the contactor to disconnect when the battery current is greater than or equal to a preset current threshold and less than a maximum allowable current of the contactor.

A third aspect of the present disclosure provides a vehicle, including a battery, and a battery protection system provided according to the first aspect of the present disclosure.

In the above technical solution, by setting a circuit breaker on the main circuit, when the current exceeds the maximum allowable current of the contactor, the controller controls the circuit breaker to disconnect. In this way, when the battery current exceeds the contactor's limit due to current overload, short circuit or collision. When the maximum allowable current is reached, the main circuit can be cut off in time by the circuit breaker. The circuit breaker responds quickly and can effectively protect the main circuit, thereby covering the protection blind area that cannot be covered by contactors and fuses, and reducing the battery overheating or even fire due to excessive current. possibility of explosion.

Other features and advantages of the present disclosure will be described in detail in the detailed description that follows.

Description of drawings

The accompanying drawings are used to provide a further understanding of the present disclosure, and constitute a part of the specification, and together with the following detailed description, are used to explain the present disclosure, but not to limit the present disclosure. In the attached image:

FIG. 1 is a schematic diagram of a system structure of a battery protection system provided by an exemplary embodiment.

FIG. 2 is a partial structural schematic diagram of a battery protection system provided by another exemplary embodiment.

FIG. 3 is a schematic diagram of a connection structure of a circuit breaker in a battery protection system provided by another exemplary embodiment.

FIG. 4 is a flowchart of a battery protection method provided by an exemplary embodiment.

FIG. 5 is a flowchart of a battery protection method provided by another exemplary embodiment.

FIG. 6 is a flowchart of a battery protection method provided by yet another exemplary embodiment.

Description of reference numerals

1-fuse, 21-first contactor, 22-second contactor, 3-circuit breaker, 4-current detection device, 5-main circuit, 6-charging circuit, 61-charging positive circuit, 62-charging negative Circuit, 71-discharge positive circuit, 72-discharge negative circuit, 8-charging interface, 9-discharging interface, 10 battery.

Detailed ways

The specific embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present disclosure, but not to limit the present disclosure.

First, the possible application scenarios of the present disclosure will be described. In order to solve the situation of excessive current caused by overload, short circuit or collision on the circuit where the battery is located, a contactor and a fuse are generally set in the circuit to cut off the circuit when the current is too large.

However, since the maximum allowable passing current of the contactor is less than the fusing current of the fuse, there is a protection dead zone in the battery circuit where the contactor and the fuse are set, which neither the contactor nor the fuse can cover. When the battery is inside, the contactor cannot operate and the fuse cannot be blown, which may easily cause the battery temperature to be too high or even catch fire.

In order to solve the above existing technical problems, a first aspect of the present disclosure provides a battery protection system.

FIG. 1 is a schematic diagram of a system structure of a battery protection system provided by an exemplary embodiment, and FIG. 2 is a schematic diagram of a partial structure of a battery protection system provided by another exemplary embodiment. 1 and 2, the battery protection system may include a fuse 1, which is provided on the main circuit 5 of the battery 10; a contactor, which is provided on the charging circuit 6 and the discharging circuit of the battery 10; and a circuit breaker 3, which is provided on the battery 10. On the main circuit 5 of When the current is greater than or equal to the maximum allowable current of the contactor, the circuit breaker 3 is controlled to open to cut off the main circuit 5 .

In this way, by setting the circuit breaker 3 on the main circuit 5, when the current exceeds the maximum allowable current of the contactor, the controller controls the circuit breaker 3 to disconnect, so that when the battery current exceeds the contactor's limit due to current overload, short circuit or collision When the maximum allowable current is reached, the main circuit 5 can be cut off in time through the circuit breaker 3, the circuit breaker 3 responds quickly, can effectively protect the main circuit 5, cover the protection blind area that the contactor and fuse 1 cannot cover, and reduce the battery 10 caused by excessive current. The temperature is too high or even the possibility of fire and explosion.

1 , the battery 10 may include a plurality of battery cells, the plurality of battery cells are connected in series on the main circuit 5, and the fuse 1 may be provided between the plurality of battery cells.

1, the charging circuit 6 may include a charging positive circuit 61 and a charging negative circuit 62, the main circuit 5 has a positive terminal and a negative terminal, the positive terminal of the main circuit 5 is connected to the charging positive circuit 61, and the main circuit 5 has a positive terminal. The negative terminal is connected to the charging negative circuit 62 , and the contactor may include a first contactor 21 , and the first contactor 21 is provided on the charging positive circuit 61 and the charging negative circuit 62 .

1, the discharge circuit may include a discharge positive circuit 71 and a discharge negative circuit 72, the main circuit 5 has a positive terminal and a negative terminal, the positive terminal of the main circuit 5 is connected to the discharge positive circuit 71, and the negative terminal of the main circuit 5 is connected. The terminal is connected to the discharge negative circuit 72 , and the contactor may further include a second contactor 22 , and the second contactor 22 is arranged on the discharge positive circuit 71 and the discharge negative circuit 72 .

Exemplarily, referring to FIG. 1 , the solution of the present disclosure can be applied to the interior of a battery pack. The battery pack is provided with a plurality of discharge ports 9 . The negative terminal of the battery is connected to the discharge negative circuit 72, so that when the second contactor 22 on the discharge positive circuit 71 is disconnected, or the second contactor 22 on the discharge negative circuit 72 is disconnected, all the discharge interfaces 9 are connected to the battery The connection circuit 10 is disconnected, and the battery 10 stops discharging.

1, the battery pack is provided with a charging interface 8, the positive terminal of the charging interface 8 is connected to the charging positive circuit 61, and the negative terminal of the charging interface 8 is connected to the charging negative circuit 62. When the first contactor 21 is disconnected, or the first contactor 21 on the charging negative circuit 62 is disconnected, the connection circuit between the charging interface 8 and the battery 10 is disconnected, and the battery 10 stops charging.

It should be noted that the above-mentioned preferred embodiments are only used to illustrate the principle of the present disclosure, and are not intended to limit the protection scope of the present disclosure. On the premise of not departing from the principles of the present disclosure, those skilled in the art can adjust the above setting manners, so that the present disclosure can be applied to more specific application scenarios.

For example, there may be multiple charging ports 8 , the positive terminals of the multiple charging ports 8 are all connected to the charging positive circuit 61 , and the negative terminals of the multiple charging ports 8 are all connected to the charging negative circuit 62 . In this way, when the first contactor 21 on the charging positive circuit 61 is disconnected, or the first contactor 21 on the charging negative circuit 62 is disconnected, all the charging ports 8 are disconnected from the battery 10 and the battery 10 stops charging.

For another example, the first contactor 21 may be one and disposed on the charging positive circuit 61 or the charging negative circuit 62. When the first contactor 21 is disconnected, the battery 10 stops charging.

Similarly, the second contactor 22 can also be set as one and disposed on the discharge positive circuit 71 or the discharge negative circuit 72. When the second contactor 22 is disconnected, the battery 10 stops discharging.

It can be understood that a plurality of first contactors 21 can be respectively provided on the charging positive circuit 61 and the charging negative circuit 62, and a plurality of second contactors 22 can be respectively provided on the discharging positive circuit 71 and the discharging negative circuit 72. Both the contactor 21 and each of the second contactors 22 are connected to the controller, which can also achieve the beneficial effects of the above-mentioned embodiments, which will not be repeated here.

Exemplarily, referring to FIG. 1 , the current detection device 4 may be a current sensor, the current sensor is arranged on the main circuit 5 in series, and the current sensor is connected in communication with the controller.

Alternatively, the current detection device 4 can also be a shunt and a current measurement device matched with it, and the current measurement device is connected in communication with the controller. Since the usage of the shunt is in the prior art, it will not be repeated here.

Alternatively, the current detection device 4 may also be a circuit characteristic value measurement device, and a current measurement module matched with it is integrated in the controller.

Specifically, for example, the circuit characteristic value measurement device may be a voltage measurement device connected in parallel with an element having a fixed resistance value, and the voltage measurement device is communicatively connected to the controller. The resistance value of the element is pre-stored in the controller. After receiving the signal from the voltage measurement device, the current measurement module converts the pre-stored resistance value and the measured voltage value to determine the current value.

Optionally, the circuit breaker 3 is also directly connected in communication with the crash sensor, for automatically disconnecting in response to a crash signal generated by the crash sensor.

In this solution, when the vehicle collides, the collision sensor sends a collision signal to the circuit breaker 3, and the circuit breaker 3 automatically opens in response to the collision signal of the collision sensor. In this way, when the vehicle collides, the circuit breaker 3 can quickly cut off the main circuit 5, stop charging or discharging of the battery 10, avoid short circuit due to the collision, and improve safety.

It should also be pointed out that due to the direct communication connection between the collision sensor and the circuit breaker 3, the collision signal of the collision sensor is directly sent to the circuit breaker 3, which can greatly shorten the response time, quickly cut off the circuit, and reduce the occurrence of excessive temperature or even fire and explosion caused by instantaneous short circuit. possible.

For example, after receiving the collision signal from the collision sensor, the circuit breaker 3 can complete the cut-off work within 3ms.

Through the above arrangement, in the case of non-collision, the circuit breaker 3 can disconnect the main circuit 5 when the battery current is greater than the maximum allowable current of the contactor, and directly disconnect the main circuit 5 in the event of a collision, which can greatly improve the safety of the battery 10 This reduces the possibility of high temperature or even explosion of the battery 10 due to excessive current.

Exemplarily, FIG. 3 is a schematic diagram of a connection structure of a circuit breaker 3 in a battery protection system provided by another exemplary embodiment. Referring to FIG. 3 , when the battery pack adopts active balance management, the circuit breaker 3 communicates with the collision sensor through ABM (English: Active Balance Management, Chinese: Active Balance Management).

Optionally, the controller can also be used to control the circuit breaker 3 to open to cut off the main circuit 5 when the battery current is greater than or equal to the maximum allowable current of the contactor and less than or equal to the fusing current of the fuse 1 .

Through the above setting method, when the battery current is greater than or equal to the maximum allowable current of the contactor, and less than or equal to the fusing current of the fuse 1, the controller can control the circuit breaker 3 to open, so that the main circuit 5 can be cut off quickly.

Especially when the battery current is close to or reaches the fusing current of the fuse 1, since the fusing of the fuse 1 takes a certain time, and the battery current is close to or reaches the intensity of the fusing current for a certain period of time, the risk of the battery 10 catching fire will be greatly increased. In this solution, the circuit breaker 3 cuts off the main circuit 5 and the response time is fast, which can greatly reduce the possibility of the battery 10 being overheated or even catching fire and exploding.

Referring to FIG. 3 , optionally, the controller may be a BMS (Battery Management System in English, battery management system in Chinese), so that the battery protection system is integrated in the battery pack, which can reduce the interference of the external environment and increase the reliability. At the same time, when the battery pack is detached from the vehicle body, or the vehicle controller fails, the battery protection system can still work reliably, so as to better protect the battery 10 .

Alternatively, the controller may also be a vehicle controller, and the vehicle controller is connected in communication with the contactor, the circuit breaker 3 and the current detection device 4 .

Optionally, the vehicle controller may directly communicate with the contactor, the circuit breaker 3 and the current detection device 4 through CAN (English: Controller Area Network, Chinese: Controller Area Network).

Alternatively, the vehicle controller can also communicate with the contactor, the circuit breaker 3 and the current detection device 4 through the BMS.

Alternatively, the controller may also be a domain controller.

Exemplarily, during the operation of the battery 10, the current information of the current detection device 4 is sent to the corresponding domain controller through the gateway. When the domain controller determines that the contactor or circuit breaker 3 is to be cut off, the domain controller will The information is sent to the contactor or circuit breaker 3 through the gateway to cause the contactor or circuit breaker 3 to open.

A second aspect of the present disclosure provides a battery protection method. FIG. 4 is a flowchart of the battery protection method provided by an exemplary embodiment. Referring to FIG. 4 , the battery protection method may include:

Step S11, detecting the battery current flowing through the battery;

Exemplarily, the battery current can be directly detected by a current measuring device, for example, directly measured by a current detection element disposed on the loop.

Alternatively, it can also be obtained by measuring other characteristic values related to the battery current.

For example, the voltage across an element connected in series on the loop can be measured, and the battery current can be converted from the voltage and the resistance of the element.

For another example, the battery current can be finally obtained by measuring the current of each loop, and summing or differing the measured current values according to the series-parallel relationship.

Step S12, when the battery current is greater than or equal to the maximum allowable current of the contactor arranged on the charging circuit and/or the discharging circuit of the battery, the circuit breaker arranged on the main circuit of the battery is controlled to be disconnected to cut off the main circuit .

In this way, when the battery current exceeds the maximum allowable current of the contactor due to current overload, short circuit or collision, the main circuit can be cut off in time through the circuit breaker, the circuit breaker responds quickly, and can effectively protect the main circuit, covering the contactor and fuse. Covered protection blind area reduces the possibility of battery overheating or even fire and explosion due to excessive current.

FIG. 5 is a flowchart of a battery protection method provided by another exemplary embodiment. Referring to FIG. 5 , before step S12 , the method in FIG. 4 may further include: step S13 , judging whether the battery current is greater than or equal to a preset threshold, and generating a first judgment result.

Exemplarily, the preset threshold corresponds to the battery current value when overloaded. When the battery current is greater than or equal to the preset threshold, an overload or short circuit occurs.

Therefore, if the first determination result is YES, step S12 is executed.

Exemplarily, referring to FIG. 5, step S12 in FIG. 4 may specifically include step S121 and step S122, in the case that the first judgment result is yes, execute step S121: judge whether the battery current is less than the maximum allowable current of the contactor, A second judgment result is generated.

In the case that the second judgment result is no, step S122 is executed: the circuit breaker provided on the main circuit of the battery is controlled to be disconnected, so as to cut off the main circuit.

Exemplarily, referring to FIG. 5, the method in FIG. 4 may further include step S14, in the case that the second judgment result is yes, perform step S14: control the contactor provided on the main circuit of the battery to be disconnected to cut off main circuit.

In this way, when the battery current is less than the maximum allowable current of the contactor, the main circuit can be cut off directly through the contactor.

Wherein, the relevant specific implementations of the main circuit, the discharge circuit, and the charging circuit have been described in detail in the embodiments of the system, and will not be described in detail here.

Exemplarily, a prompting device may also be provided in the vehicle, and if the first judgment result is yes, the prompting device is controlled to prompt an alarm message corresponding to excessive battery current, so that the driver can know the battery state in time and take braking action. , leaving the car and other measures to ensure the safety of the occupants in the car.

Exemplarily, the prompting device may be an in-vehicle display.

Alternatively, the prompting device may also be an audio player in the vehicle.

Through steps S121, S122 and S14, a contactor or circuit breaker can be selected according to the magnitude of the battery current to disconnect the main circuit during overload or short circuit, thereby improving safety, and at the same time, when the battery current exceeds the preset threshold and does not reach the fuse In the case of the fuse current of the contactor, the main circuit is cut off in time to eliminate the protection dead zone between the contactor and the fuse.

FIG. 6 is a flowchart of a battery protection method provided by yet another exemplary embodiment. Referring to FIG. 6, for the method in FIG. 5, step S12 may further include step S123, in the case that the second judgment result is no, step S123 is executed: judging whether the battery current is less than or equal to the fusing current of the circuit breaker, and generating a third critical result.

In the case where the third determination result is YES, step S122 is executed to cut off the main circuit by opening the circuit breaker.

For example, the maximum allowable current of the contactor is 1000A, and the fusing current of the fuse is 3000A. When the battery current is greater than the preset threshold and less than 1000A, the contactor is controlled to disconnect to cut off the main circuit; when the battery current is greater than or equal to 1000A and When the current is less than or equal to 3000A, the main circuit is cut off by the circuit breaker; when the battery current is greater than 3000A, the fuse is automatically blown to disconnect the main circuit.

With the above arrangement, even if the battery current reaches the fusing current of the fuse, the battery current is still cut off by the circuit breaker. Since it takes a certain time for the fuse to blow, and the battery current is close to or reaches the intensity of the fuse current for a certain period of time, the risk of battery fire will be greatly increased. In this solution, the circuit breaker cuts off the main circuit and has a fast response time, which can greatly reduce the possibility of the battery temperature being too high or even the possibility of fire and explosion.

At the same time, it should also be pointed out that through the above setting method, the battery current interval corresponding to the contactor, circuit breaker 3 and fuse 1 can be accurately divided, which is convenient for the control background to accurately record the working data. If a fault occurs, it is convenient to quickly determine the problem. parts, so that deficiencies can be identified and improved in time, reducing troubleshooting time.

A third aspect of the present disclosure provides a vehicle, including a battery, and a battery protection system provided according to the first aspect of the present disclosure.

The preferred embodiments of the present disclosure have been described above in detail with reference to the accompanying drawings. However, the present disclosure is not limited to the specific details of the above-mentioned embodiments. Various simple modifications can be made to the technical solutions of the present disclosure within the scope of the technical concept of the present disclosure. These simple modifications all fall within the protection scope of the present disclosure. For example, although the fuses are arranged between a plurality of battery cells in the exemplary embodiment, the fuses may also be arranged at other positions of the main circuit, and the technical effects of the above-mentioned embodiments can also be achieved.

In addition, it should be noted that the specific technical features described in the above-mentioned specific implementation manner can be combined in any suitable manner if there is no contradiction. For example, different numbers of a contactor and a second contactor. In order to avoid unnecessary repetition, various possible combinations are not described in the present disclosure.

In addition, the various embodiments of the present disclosure can also be arbitrarily combined, as long as they do not violate the spirit of the present disclosure, they should also be regarded as the contents disclosed in the present disclosure.

Claims (10)

1. A battery protection system, comprising:

a fuse disposed on a main circuit of the battery;

the contactor is arranged on a charging circuit and/or a discharging circuit of the battery;

a circuit breaker disposed on a main circuit of the battery;

current detection means for detecting a battery current flowing through the battery;

and the controller is in communication connection with the current detection device and the circuit breaker and is used for controlling the circuit breaker to be opened to cut off the main loop under the condition that the current of the battery is greater than or equal to the maximum allowable current of the contactor.

2. The battery protection system of claim 1, wherein the circuit breaker is further in direct communication with a crash sensor for automatic opening in response to a crash signal generated by the crash sensor.

3. The battery protection system of claim 1, wherein the controller is configured to control the circuit breaker to open to break the main circuit if the battery current is greater than or equal to a maximum allowable current of the contactor and less than or equal to a fuse current of the fuse.

4. The battery protection system of claim 1, wherein the controller is further communicatively coupled to the contactor for controlling the contactor to open if the battery current is greater than or equal to a predetermined current threshold and less than a maximum allowable current of the contactor.

5. The battery protection system of claim 4, wherein the contactor comprises a first contactor disposed on the charging loop, and wherein the controller is configured to control the first contactor to open if the battery current is greater than or equal to a preset current threshold and less than a maximum allowable current of the first contactor when the battery is in the charging mode.

6. The battery protection system of claim 4, wherein the contactor comprises a second contactor disposed on the discharge circuit, and the controller is configured to control the second contactor to open if the battery current is greater than or equal to a preset current threshold and less than a maximum allowable current of the second contactor when the battery is in a discharge mode.

7. The battery protection system of any one of claims 1-6, wherein the controller is one of: battery management system, domain controller, vehicle control unit.

8. A method of protecting a battery, comprising:

detecting a battery current flowing through the battery;

and controlling a breaker arranged on a main loop of the battery to be opened so as to break the main loop under the condition that the current of the battery is greater than or equal to the maximum allowable current of a contactor arranged on a charging loop and/or a discharging loop of the battery.

9. The battery protection method of claim 8, further comprising:

and controlling the contactor to be opened under the condition that the battery current is greater than or equal to a preset current threshold value and is less than the maximum allowable current of the contactor.

10. A vehicle comprising a battery, characterized by further comprising the battery protection system according to any one of claims 1 to 7.

Images