Battery pack insulation detection circuit and method and vehicle

Abstract

The invention relates to a battery pack insulation detection circuit and method and a vehicle. The circuit comprises a battery pack, a first detection branch, a second detection branch, a first voltage detection device, a second voltage detection device and a processing device, the first voltage detection device and the second voltage detection device are used for detecting first voltage and second voltage between the positive electrode end and the grounding end of the battery pack and between the negative electrode end and the grounding end of the battery pack when one of the first detection branch circuit and the second detection branch circuit is in an on state and the other one is in an off state, and detecting the first voltage and the second voltage between the positive electrode end and the grounding end of the battery pack when both are in the on state. Respectively detecting a third voltage and a fourth voltage between the positive end and the negative end of the battery pack and the grounding end; and the processing device is used for determining the external insulation state of the battery pack according to the first voltage, the second voltage, the third voltage and the fourth voltage. Therefore, the insulation state of the power battery pack can be accurately determined, the driving safety is improved, and the circuit is simple, practical and easy to implement.

Description

technical field [0001] The present disclosure relates to the field of vehicles, in particular, to a battery pack insulation detection circuit, method and vehicle. Background technique [0002] With the rapid development of the electric vehicle industry and the increase in the number of electric vehicles, people pay more and more attention to the safety of electric vehicles. The power battery pack of an electric vehicle has the characteristics of high voltage and large charging and discharging current, so the insulation performance is an important factor to ensure the safety of the entire electric vehicle. If there is insulation failure in the electrical system of electric vehicles, it may cause different degrees of harm. If only one point of the electrical system has insulation failure, there will be no serious impact for the time being. Once more insulation failures occur at more points, the system will leak electricity. In severe cases, heating in the leakage area may ca...

AI Technical Summary

Problems solved by technology

The existing resistance detection method cannot accurately determine the resistance value of the insulation resistance when the insulation resistance of the positive pole of the power battery pack and the insulation resistance of the negative pole decrease in the same trend, and thus cannot accurately determine the insulation state of the power battery pack.

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