Method and device for detecting insulation fault of power battery system

Abstract

The invention discloses a method and device for detecting an insulation fault of a power battery system, and the method comprises the steps: detecting an insulation value between the power battery system and a vehicle frame after an insulation fault of a whole vehicle high-voltage loop is detected and positive and negative high-voltage relays are turned off, and comparing the insulation value with a preset value; determining that an insulation fault happens to a power battery in the whole vehicle high-voltage loop if the insulation value is less than the preset value, and enabling a message that the insulation fault happens to the power battery to be transmitted to a whole vehicle controller; judging that the insulation fault happens to a high-voltage load, except the power battery, in the whole vehicle high-voltage loop if the insulation value is not less than the preset value, and transmitting a message that the insulation fault happens to the high-voltage load, except the power battery, in the whole vehicle high-voltage loop to the whole vehicle controller. The method can determine that the insulation fault happens to the power battery or other high-voltage loads, thereby greatly reducing the inspection difficulty of the insulation fault of the vehicle. The method does not need to carry out the disassembly of a connector assembly in the insulation inspection process of the whole vehicle, and improves the connection reliability of devices.

Description

technical field [0001] The invention relates to the technical field of electric vehicle power battery systems, in particular to a power battery system insulation fault detection method and a power battery system insulation fault detection device. Background technique [0002] The power battery is one of the key components of electric vehicles such as energy-saving vehicles and new energy vehicles. It is the source of driving force for the vehicle, which is equivalent to the fuel tank of a traditional vehicle and stores the electric energy required for driving the vehicle. Generally, the voltage of the power battery for vehicles is relatively high, and the voltage is basically greater than or equal to 300V (volts). According to the national standard "GBT19751-2005 Safety Requirements for Hybrid Electric Vehicles", the maximum voltage is higher than or equal to 60V (DC) or 25V (AC) as high voltage. Vehicle power batteries must meet the requirements of the national standard "G...

AI Technical Summary

Problems solved by technology

[0005] In order to meet the requirements of the vehicle and improve the reliability of the connection, the high-voltage connector needs to use one or more mechanical locks, and some mechanical locks can only be opened with the help of auxiliary tools, which greatly reduces the efficiency of power battery insulation inspection.

Moreover, high-voltage connectors and manual maintenance switches are generally required to be plugged in and out, so disassembly and assembly also reduce the reliability of their connection and work.

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