Adhesion detection protective circuit for automobile battery relays

Abstract

The invention belongs to the technical field of automobile battery management and particularly relates to an adhesion detection protective circuit for automobile battery relays. The adhesion detection protective circuit comprises a battery management unit (BMU), a battery pack, the main positive relay and the main negative relay. The main positive relay is arranged at the positive pole of the battery pack. The main negative relay is arranged at the negative pole of the battery pack. The BMU is used for controlling switching-off and switching-on of the main positive relay and the main negative relay. The BMU comprises four pins. Two of the four pins are electrically connected with the positive pole and the negative pole which are located at the two ends of the main positive relay correspondingly. The other two of the four pins are electrically connected with the positive pole and the negative pole which are located at the two ends of the main negative relay correspondingly. The four pins are used for detecting the voltage of the main positive relay and the voltage of the main negative relay. When the relays break down, the BMU directly detects the adhesion state or disconnection state of the two relays through the pins, the state of the relays can be detected visually, and the BMU can be effectively prevented from misreporting the state.

Description

technical field [0001] The invention belongs to the technical field of automobile battery management, in particular to an automobile battery relay adhesion detection protection circuit. Background technique [0002] New energy has now become a hot topic in all walks of life. New energy vehicles (electric vehicles) are one of the most important members of new energy, and the development trend is gratifying. Bring new opportunities for electric vehicles to provide power source car batteries. Usually, a car battery is composed of a battery pack, BMU, BMS, Hall sensor, various relays, pre-charging resistors, fuses and other devices. The battery pack provides electric energy for the vehicle, the BMU communicates with the vehicle controller VCU and the motor control unit MCU, and the battery pack is connected to the electrical components of the vehicle body through the main relay. The BMU accepts the vehicle communication command to control the closing and separation of each re...

AI Technical Summary

Problems solved by technology

[0004] In order to solve the problem in the prior art that the poor adhesion of the relay leads to the CAN error report of the whole vehicle, the present invention provides a circuit capable of detecting the state of the relay. The battery management unit BMU can directly detect the state of the relay, and the CAN feedback communication is accurate.

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