A low-voltage insulation test system for lithium battery modules

Abstract

The application provides a lithium battery module low-voltage insulation test system in the technical field of battery module test, which comprises an industrial computer, a PLC, an insulation withstand voltage instrument, an insulation test circuit, a test needle bed, a first isolation transformer, a second isolation transformer, a switching power supply, a multimeter, an internal resistance instrument and a plurality of heavy load connectors; the industrial computer, the PLC, the insulation withstand voltage instrument, the insulation test circuit and the test needle bed are connected in sequence; the PLC is connected with the multimeter and the internal resistance instrument respectively; the output end of the first isolation transformer is connected with the insulation withstand voltage instrument; the input end of the switching power supply is connected with the second isolation transformer, and the output end is connected with the insulation test circuit; the insulation test circuit is connected with the test needle bed through the heavy load connector and is used for separating each test circuit of the insulation test circuit. The application has the advantages that the lithium battery module low-voltage insulation test precision is greatly improved.

Description

Technical Field

[0001] This invention relates to the field of battery module testing technology, and in particular to a low-voltage insulation testing system for lithium battery modules. Background Technology

[0002] With the increasing depletion of traditional energy sources and the numerous problems exposed in their production and use, the development of new energy sources has become a general consensus. Among them, lithium battery modules, as the power source for new energy vehicles, are in increasing demand, which also places higher requirements on the testing accuracy of low-voltage insulation testing of lithium battery modules.

[0003] However, traditionally, the relevant factors of the test circuit that may affect the low-voltage insulation test results have not been adequately considered, resulting in a certain deviation between the test values ​​and the actual values ​​in terms of test accuracy. This affects the performance evaluation of lithium battery modules. Furthermore, due to the low test accuracy, a large number of lithium battery modules need to be tested repeatedly to improve accuracy, which increases the workload and reduces production efficiency.

[0004] Therefore, how to provide a low-voltage insulation testing system for lithium battery modules to improve the accuracy of low-voltage insulation testing has become an urgent technical problem to be solved. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a low-voltage insulation testing system for lithium battery modules, thereby improving the accuracy of low-voltage insulation testing of lithium battery modules.

[0006] The present invention is implemented as follows: a low-voltage insulation test system for lithium battery modules, comprising an industrial computer, a PLC, an insulation withstand voltage tester, an insulation test circuit, a test probe bed, a first isolation transformer, a second isolation transformer, a switching power supply, a multimeter, an internal resistance meter, and several heavy-duty connectors.

[0007] The industrial control computer, PLC, insulation withstand voltage tester, insulation test circuit, and test probe bed are connected in sequence; the PLC is connected to a multimeter and an internal resistance meter respectively; the output terminal of the first isolation transformer is connected to the insulation withstand voltage tester; the input terminal of the switching power supply is connected to the second isolation transformer, and the output terminal is connected to the insulation test circuit.

[0008] The insulation test circuit is connected to the test probe bed via a heavy-duty connector, which is used to separate the test lines of the insulation test circuit.

[0009] Furthermore, the insulation test circuit includes a relay main board, a first relay sub-board, a second relay sub-board, a third relay sub-board, and a fourth relay sub-board;

[0010] The input terminal of the relay main board is connected to the insulation withstand voltage tester, the positive output pin A+ is connected to the first relay sub-board, the negative output pin B- is connected to the second relay sub-board, the positive output pin A- is connected to the third relay sub-board, and the negative output pin B+ is connected to the fourth relay sub-board; both the first and third relay sub-boards are connected to the switching power supply.

[0011] Furthermore, the first relay sub-board, the second relay sub-board, the third relay sub-board, and the fourth relay sub-board each include four relays, and each relay is connected to the test bed via a heavy-duty connector.

[0012] Furthermore, it also includes:

[0013] A set of operation buttons is connected to the industrial control computer.

[0014] Furthermore, it also includes:

[0015] An alarm light is connected to the industrial control computer.

[0016] The advantages of this invention are:

[0017] By setting up an insulation test circuit and connecting it to a bed of test probes using a heavy-duty connector, the test lines of the insulation test circuit are isolated, ensuring that only one polarity exists in a single heavy-duty connector. A separate power supply is used to power the positive output pins A+ and A- of the insulation withstand voltage tester. A second isolation voltage regulator isolates and regulates the power supply, while a first isolation voltage regulator isolates and regulates the insulation withstand voltage tester, avoiding leakage current caused by sharing a power supply. Furthermore, the insulation test circuit includes a first, second, third, and fourth relay sub-board. During testing, each line of the lithium battery module is connected to a separate sub-board, ensuring complete separation of positive and negative terminals. These triple measures significantly improve the accuracy of low-voltage insulation testing of the lithium battery module. Attached Figure Description

[0018] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0019] Figure 1 This is a circuit block diagram of a low-voltage insulation testing system for lithium battery modules according to the present invention.

[0020] Figure 2 This is a circuit diagram illustrating the insulation test circuit of the present invention. Detailed Implementation

[0021] The overall concept of the technical solution in this application embodiment is as follows: Each test line of the insulation test circuit is separated by a heavy-duty connector (isolation of the bed-of-needles test circuit); a switching power supply is set to independently power the positive output pins A+ and A- of the insulation withstand voltage tester; a second isolation voltage regulator isolates and regulates the switching power supply; a first isolation voltage regulator isolates and regulates the insulation withstand voltage tester, avoiding leakage current caused by sharing the power supply (power supply isolation); during testing, each path of the lithium battery module is connected to a sub-board of the insulation test circuit to ensure complete separation of the positive and negative terminals during testing (increasing distance), thereby improving the accuracy of low-voltage insulation testing of the lithium battery module.

[0022] Please refer to Figures 1 to 2 As shown, a preferred embodiment of the low-voltage insulation testing system for lithium battery modules of the present invention includes an industrial control computer, a PLC, an insulation withstand voltage tester, an insulation test circuit, a test probe bed, a first isolation transformer, a second isolation transformer, a switching power supply, a multimeter, an internal resistance meter, and several heavy-duty connectors.

[0023] The industrial control computer controls the operation of the low-voltage insulation testing system; the PLC executes the instructions issued by the industrial control computer; the insulation withstand voltage tester performs insulation withstand voltage tests on the lithium battery module; the insulation test circuit connects to the lithium battery module to be tested; the test probe bed directly contacts the terminals of the lithium battery module; the first isolation transformer and the second isolation transformer provide isolation and voltage regulation; the switching power supply supplies power to the positive output of the insulation withstand voltage tester; the multimeter measures the voltage of the lithium battery module; the internal resistance meter measures the internal resistance of the lithium battery module; and the heavy-duty connector separates the test lines of the insulation test circuit.

[0024] The industrial control computer, PLC, insulation withstand voltage tester, insulation test circuit, and test probe bed are connected in sequence; the PLC is connected to a multimeter and an internal resistance meter respectively; the output terminal of the first isolation transformer is connected to the insulation withstand voltage tester; the input terminal of the switching power supply is connected to the second isolation transformer, and the output terminal is connected to the insulation test circuit.

[0025] The insulation test circuit is connected to the test probe bed via a heavy-duty connector, which is used to separate the test lines of the insulation test circuit.

[0026] The insulation test circuit includes a main relay board, a first sub-relay board, a second sub-relay board, a third sub-relay board, and a fourth sub-relay board;

[0027] The input terminal of the relay main board is connected to the insulation withstand voltage tester, the positive output pin A+ is connected to the first relay sub-board, the negative output pin B- is connected to the second relay sub-board, the positive output pin A- is connected to the third relay sub-board, and the negative output pin B+ is connected to the fourth relay sub-board; both the first and third relay sub-boards are connected to the switching power supply.

[0028] The positive and negative outputs of the insulation withstand voltage tester are connected to the insulation test circuit. Experimental verification shows that when the test current passes through the relay, the power supply of the relay where the positive current is located is significantly isolated, while the power supply of the relay where the negative output is located has little impact on the impedance of the entire test circuit. Therefore, the switching power supply is connected to the first relay sub-board and the third relay sub-board.

[0029] The first relay sub-board, the second relay sub-board, the third relay sub-board, and the fourth relay sub-board each include four relays, and each relay is connected to the test bed via a heavy-duty connector.

[0030] Also includes:

[0031] An operating button set, connected to the industrial control computer, is used to control the low-voltage insulation testing system.

[0032] Also includes:

[0033] An alarm light, connected to the industrial control computer, is used for fault alarms in the low-voltage insulation testing system.

[0034] Working principle of this invention:

[0035] The lithium battery module to be tested is placed on the test probe bed, so that the test circuit is connected to the terminal of the lithium battery module through the test probe bed; the industrial control computer sends an insulation test command to the PLC based on the trigger signal of the operation button group, and the PLC controls the insulation withstand voltage tester to perform the insulation test based on the received insulation test command.

[0036] In summary, the advantages of this invention are as follows:

[0037] By setting up an insulation test circuit and connecting it to a bed of test probes using a heavy-duty connector, the test lines of the insulation test circuit are isolated, ensuring that only one polarity exists in a single heavy-duty connector. A separate power supply is used to power the positive output pins A+ and A- of the insulation withstand voltage tester. A second isolation voltage regulator isolates and regulates the power supply, while a first isolation voltage regulator isolates and regulates the insulation withstand voltage tester, avoiding leakage current caused by sharing a power supply. Furthermore, the insulation test circuit includes a first, second, third, and fourth relay sub-board. During testing, each line of the lithium battery module is connected to a separate sub-board, ensuring complete separation of positive and negative terminals. These triple measures significantly improve the accuracy of low-voltage insulation testing of the lithium battery module.

[0038] While specific embodiments of the present invention have been described above, those skilled in the art should understand that the specific embodiments described are merely illustrative and not intended to limit the scope of the present invention. Equivalent modifications and variations made by those skilled in the art in accordance with the spirit of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A low-voltage insulation testing system for lithium battery modules, characterized in that: It includes an industrial control computer, a PLC, an insulation withstand voltage tester, an insulation test circuit, a test probe bed, a first isolation transformer, a second isolation transformer, a switching power supply, a multimeter, an internal resistance meter, and several heavy-duty connectors. The industrial control computer, PLC, insulation withstand voltage tester, insulation test circuit, and test probe bed are connected in sequence; the PLC is connected to a multimeter and an internal resistance meter respectively; the output terminal of the first isolation transformer is connected to the insulation withstand voltage tester; the input terminal of the switching power supply is connected to the second isolation transformer, and the output terminal is connected to the insulation test circuit. The insulation test circuit is connected to the test probe bed via a heavy-duty connector, which is used to separate the test lines of the insulation test circuit. The insulation test circuit includes a main relay board, a first sub-relay board, a second sub-relay board, a third sub-relay board, and a fourth sub-relay board; The input terminal of the relay main board is connected to the insulation withstand voltage tester, the positive output pin A+ is connected to the first relay sub-board, the negative output pin B- is connected to the second relay sub-board, the positive output pin A- is connected to the third relay sub-board, and the negative output pin B+ is connected to the fourth relay sub-board; both the first and third relay sub-boards are connected to the switching power supply.

2. The low-voltage insulation testing system for lithium battery modules as described in claim 1, characterized in that: The first relay sub-board, the second relay sub-board, the third relay sub-board, and the fourth relay sub-board each include four relays, and each relay is connected to the test bed via a heavy-duty connector.

3. The low-voltage insulation testing system for lithium battery modules as described in claim 1, characterized in that: Also includes: A set of operation buttons is connected to the industrial control computer.

4. The low-voltage insulation testing system for lithium battery modules as described in claim 1, characterized in that: Also includes: An alarm light is connected to the industrial control computer.

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