汽车继电器触点瞬态接触电场数值分析

王燕兵　赖雅丽　

摘 要：繼电器是车辆电器控制的重要控制元器件，其工作环境是瞬间大电流通过周期性闭合的触点，由于接触触点间接触电阻在闭合瞬间大电流的作用下产生焦耳热，导致触点极易发生熔焊的可能，严重影响继电器的使用性能，危害行车安全。为此，本文采用分型接触理论建立接触电阻模型，综合考虑触点间接触力、接触面积及材料的比热容、导热系数等，建立了继电器触点闭合瞬间大电流作用下的有限元模型，模拟计算触点间的电势分布及电流密度为后续接触间焦耳热计算奠定基础。

关键词：继电器 接触电阻 瞬态接触 电场

Numerical Analysis of Transient Contact Electric Field of Automotive Relay Contacts

Wang Yanbing Lai Yali

Abstract：Relay is an important control component for vehicle electrical control. Its working environment is that instantaneous high current passes through periodically closed contacts. The contact resistance between contacts generates heat under the action of the instantaneous high current of closing， resulting in contacts. It is extremely prone to welding， which seriously affects the performance of the relay and endangers driving safety. For this reason， this paper adopts the sub-type contact theory to establish a contact resistance model， comprehensively considers the contact force between contacts， contact area， specific heat capacity and thermal conductivity of materials， etc.， and establishes a finite element model under the action of a large current at the moment when the relay contacts are closed. Calculating the potential distribution and current density between contacts lays the foundation for the subsequent calculation of heat between contacts.

Key words：relay， contact resistance， transient contact， electric field