Method for monitoring short circuit and circuit break of vehicle-mounted relay or contactor coil

Abstract

The invention discloses a method for monitoring the short circuit and circuit break of a vehicle-mounted relay or contactor coil. When a detected vehicle-mounted relay or contactor coil is driven in a low-side drive manner, a detection resistor R1 is connected in parallel between the collector electrode of a driving triode Q1 of a vehicle-mounted relay or contactor and the emitter electrode of the driving triode Q1. The low-potential end of the detection resistor R1 is connected with the A/D interface of a single-chip microcomputer. The collected voltage V1 of the low-potential end of the detection resistor R1 is judged through the single-chip microcomputer. When the voltage V1 is equal to zero, the coil is judged to be in a circuit break state; when the voltage V1 is equal to a working voltage Vg of the detected vehicle-mounted relay or contactor coil, the coil is judged to be in a short circuit state. When the detected vehicle-mounted relay or contactor coil is driven in a high-side drive manner, the coil is judged to be in the short circuit state when the voltage V1 is equal to zero, and the coil is judged to be in the circuit-break state when the voltage V1 is equal to the working voltage Vg, subtracting the voltage drop of the detection resistor, of the detected vehicle-mounted relay or contactor coil. According to the invention, the employed elements are low in cost, are simple, and are easy to get. A testing method is safe and reliable, and the practicality is high.

Description

technical field [0001] The invention relates to a vehicle-mounted relay coil and a contactor, in particular to a circuit breaker and short-circuit monitoring method for the vehicle-mounted relay and the contactor coil. Background technique [0002] The high-power switching devices relays and contactors used in electric vehicles are very important for the safe operation of vehicles. A considerable part of the failure of the above-mentioned high-power switching devices is caused by open circuit or short circuit in the coil, which will affect the driving safety of electric vehicles. and driving efficiency. At present, the above-mentioned faults can only be found after the vehicle control system works, so it brings unsafe hidden dangers to the driving safety of electric vehicles. Contents of the invention [0003] The purpose of the present invention is to provide a method for monitoring the disconnection and short circuit of a vehicle-mounted relay and a contactor coil. [...

AI Technical Summary

Problems solved by technology

[0002] The high-power switching devices relays and contactors used in electric vehicles are very important for the safe operation of vehicles. A considerable part of the failure of the above-mentioned high-power switching devices is caused by open circuit or short circuit in the coil, which will affect the driving safety of electric vehicles. and driving efficiency

At present, the above faults can only be discovered after the vehicle control system is working, so it brings unsafe hidden dangers to the driving safety of electric vehicles

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