CN-121995203-A - Method and device for testing relay function of battery pack

Abstract

The application relates to the technical field of battery testing, in particular to a method and a device for testing the functions of a battery pack relay, wherein the method comprises the steps of pre-charging a high-voltage port based on a test circuit before a main positive relay is closed, and controlling the voltage difference between the inside and the outside of the battery pack after the main positive relay is closed to be within a threshold value; and (3) based on a discharging loop of the battery pack EOL test equipment, after the positive relay of the high-voltage loop is disconnected, the discharging resistor is connected to rapidly discharge the Y capacitor outside the battery pack interface so as to acquire the voltage information of the battery pack charging interface, and a function test result of the relay is obtained according to the voltage information of the charging interface. Therefore, the problems that the transient high-current discharge and other transient interference are possibly generated when the relay is closed or opened, overcurrent impact and even ablation are easily caused on the sampling chip in the control unit, so that the stable and accurate voltage value is difficult to obtain in a short time by the testing device, the abnormal action of the relay cannot be effectively identified and the like are solved.

Inventors

• CHEN ZISHENG
• Ma Jiusi
• Hu bailong
• YUAN YANAN
• Niu Zongming
• SUI HONGJUN

Assignees

• 中国第一汽车股份有限公司

Dates

Publication Date

20260508

Application Date

20251215

Claims (10)

1. 1. The battery pack relay function test method is characterized by comprising the following steps of: Constructing a test circuit for simulating the precharge and power-up process of the whole vehicle; Based on the test circuit, before the main positive relay is closed, voltage pre-charging is carried out on a high-voltage port, and the voltage difference between the inside and the outside of the battery pack after the main positive relay is closed is controlled to be within a preset threshold value; And (3) based on a discharging loop of the battery pack EOL test equipment, after the positive relay of the high-voltage loop is disconnected, connecting a discharging resistor, and rapidly discharging a Y capacitor outside a battery pack interface to acquire voltage information of a battery pack charging interface, and obtaining a function test result of the relay according to the voltage information of the charging interface.
2. 2. The method as recited in claim 1, further comprising: Collecting voltage information of a battery pack output interface; And obtaining the controlled information and/or adhesion information of the relay according to the voltage information of the output interface.
3. 3. The method of claim 1, further comprising, prior to voltage pre-charging the high voltage port: based on a preset bidirectional constant-current power supply, the vehicle-mounted DC/DC assembly pre-charging function is simulated, and the charging resistor type selection is determined so as to complete the pre-charging function.
4. 4. The method of claim 1, further comprising, prior to testing: identifying a test requirement of a user; and generating at least one test task of the battery pack relay according to the test requirement.
5. 5. A battery pack relay function test device, comprising: the construction module is used for constructing a test circuit for simulating the pre-charging and power-up process of the whole vehicle; The control module is used for carrying out voltage pre-charging on the high-voltage port before the main positive relay is closed based on the test circuit and controlling the voltage difference between the inside and the outside of the battery pack after the main positive relay is closed to be within a preset threshold value; And the testing module is used for rapidly discharging the Y capacitor outside the battery pack interface based on the discharging loop of the battery pack EOL testing equipment after the positive relay of the high-voltage loop is disconnected, so as to acquire the voltage information of the battery pack charging interface, and obtaining the function testing result of the relay according to the voltage information of the charging interface.
6. 6. The apparatus as recited in claim 5, further comprising: The acquisition module is used for acquiring voltage information of the battery pack output interface; And the acquisition module is used for acquiring the controlled information and/or adhesion information of the relay according to the voltage information of the output interface.
7. 7. The apparatus as recited in claim 5, further comprising: The simulation module is used for simulating the pre-charging function of the vehicle-mounted DC/DC assembly based on a preset bidirectional constant-current power supply and determining the charging resistor selection type so as to complete the pre-charging function.
8. 8. An electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, the processor executing the program to implement the battery pack relay function test method of any one of claims 1-4.
9. 9. A computer-readable storage medium having stored thereon a computer program, characterized in that the program is executed by a processor for implementing the battery pack relay function test method according to any one of claims 1 to 4.
10. 10. A computer program product comprising a computer program, characterized in that the computer program is executed for implementing the battery pack relay function test method according to any one of claims 1-4.

Description

Method and device for testing relay function of battery pack Technical Field The application relates to the technical field of battery testing, in particular to a method and a device for testing the functions of a battery pack relay. Background In the related art, the relay function test of the battery pack is mainly realized by controlling the closing or opening of the relay, simulating the power-on or power-off process of a high-voltage loop, and monitoring the voltage and current change of the high-voltage end of the battery pack by using basic measuring tools such as a universal meter and the like, so as to observe and judge the action states of the relay and a control unit thereof. Meanwhile, after the positive relay is disconnected, transient voltage fluctuation is easily caused, so that a testing device is difficult to acquire a stable and accurate voltage value in a short time, abnormal actions of the relay cannot be effectively identified, and the testing accuracy and reliability are affected, so that the problem needs to be solved. Disclosure of Invention The application provides a method and a device for testing the function of a battery pack relay, which are used for solving the problems that in the related art, because the relay can generate instantaneous heavy current discharge and other transient interference when being closed or opened, overcurrent impact and even ablation are easily caused on a sampling chip in a control unit, a stable and accurate voltage value is difficult to obtain in a short time by a testing device, and the abnormal action of the relay cannot be effectively identified. The embodiment of the first aspect of the application provides a battery pack relay function test method, which comprises the following steps of constructing a test circuit for simulating a whole vehicle pre-charging and electrifying process, carrying out voltage pre-charging on a high-voltage port before a main positive relay is closed based on the test circuit, controlling the voltage difference between the inside and the outside of a battery pack after the main positive relay is closed to be within a preset threshold value, based on a discharging loop of battery pack EOL (End-of-Line) test equipment, switching in a discharging resistor after a positive relay of the high-voltage loop is disconnected, carrying out rapid discharging on a Y capacitor outside a battery pack interface, so as to acquire voltage information of the battery pack charging interface, and obtaining a function test result of the relay according to the voltage information of the charging interface. Through the technical means, the embodiment of the application can perform the functional test of the relay after the voltage pre-charging and the connection of the discharge resistor to the high-voltage port, and can ensure that the action state of the relay is not influenced by transient voltage and current disturbance, thereby obtaining a stable and accurate test result, reducing the uncertainty of the test, improving the reliability and consistency of the adhesion detection, the controlled detection and the response characteristic detection of the relay, and obviously improving the efficiency and the qualification rate of the test process. Optionally, in one embodiment of the application, the method further comprises the steps of collecting voltage information of an output interface of the battery pack and obtaining controlled information and/or adhesion information of the relay according to the voltage information of the output interface. Through the technical means, the embodiment of the application can obtain the controlled information and/or the adhesion information of the relays according to the voltage information, accurately identify the actual action state of each relay under the current test instruction, and further generate the relay state judging table, thereby providing a basis for the subsequent functional test, abnormality diagnosis and whole vehicle consistency analysis. Optionally, in one embodiment of the present application, before the voltage pre-charging the high voltage port, the method further includes simulating a pre-charging function of a vehicle DC (Direct Current)/DC assembly based on a preset bi-directional constant Current power supply, and determining a charging resistor selection type to complete the pre-charging function. Through the technical means, the embodiment of the application can simulate the pre-charging function of the vehicle-mounted DC/DC assembly, determine the type of the charging resistor, truly reappear the power-on characteristic of the whole vehicle high-voltage system in the test environment, keep the voltage climbing curve of the pre-charging process, the thermal load and the current limiting capacity of the charging resistor consistent with the actual whole vehicle, and ensure that the inrush current is effectively limited in the pre-charging stage by reasonably selecting the resist