High voltage relay adhesion detection circuit of battery management system and detection method

Abstract

The invention discloses a high voltage relay adhesion detection circuit of a battery management system and a detection method. The high voltage relay adhesion detection circuit of a battery management system comprises a high voltage relay series connection branch, a freewheeling detection branch, a voltage collection branch and a battery management system. The battery management system determines the adhesion condition through controlling the on-and-off of the total positive relay, the follow current relay and the sampling voltage according to the voltage sampling branch; and when all the total positive relays and the follow current relays are switched off, the reference voltage V0 of the voltage detection end of the voltage sampling branch is detected. The invention adopts the two working channels which are a high voltage relay serial connection branch and a follow current detection branch; when adhesion of any relay of the working channel is detected, another working channel maintains the power supply output, which guarantees the normal power supply for working and realizes the fact that the adhesion of the relay can be detected during the whole operation process; and when the adhesion of the relay is detected, other relays are disconnected so as to disconnect the power supply of the system to realize the power off protection of the system.

Description

technical field [0001] The invention relates to the technical field of battery management, and more specifically relates to a high-voltage relay adhesion detection circuit and a detection method of a battery management system. Background technique [0002] With the promotion of the national new energy policy, the market share of electric vehicles is increasing, but incidents of electric vehicle fires also occur frequently. Therefore, people pay more and more attention to the safety of the power battery that provides power for electric vehicles, so the battery management system that manages the power battery has become an aspect that needs to be improved urgently. One of the main factors affecting the safety of power batteries is the adhesion of high voltage relays. The high-voltage relay is used to control the on-off of the power battery and the motor of the electric vehicle. If the high-voltage relay has adhesion problems, the high-voltage relay cannot be disconnected in t...

AI Technical Summary

Problems solved by technology

One of the main factors affecting the safety of power batteries is the adhesion of high voltage relays

The high-voltage relay is used to control the on-off of the power battery and the motor of the electric vehicle. If the high-voltage relay has adhesion problems, the high-voltage relay cannot be disconnected in time when it needs to be disconnected, which will easily lead to over-discharge and over-temperature of the power battery. There may even be serious accidents such as fire and explosion, which seriously threaten personal safety.

[0003] In the prior art, the battery management system has a variety of detection methods for high-voltage relay adhesion, but they are basically detected before the battery management system is powered on, and the high-voltage relay adhesion usually occurs when the battery management system is powered on or It is generated during the operation of the system, so the existing high-voltage relay adhesion detection method cannot detect the problem of high-voltage relay adhesion in a timely and effective manner

[0004] In addition, the existing battery management system can only detect the adhesion of the high-voltage relay, but it has not yet cut off the power supply in time when the high-voltage relay is detected, which cannot prevent the power battery from getting out of control and cannot ensure the safety of the power battery.

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