汽車繼電器觸點瞬態接觸電場數值分析

王燕兵　賴雅麗　

摘 要：繼電器是車輛電器控制的重要控制元器件，其工作環境是瞬間大電流通過周期性閉合的觸點，由于接觸觸點間接觸電阻在閉合瞬間大電流的作用下產生焦耳熱，導致觸點極易發生熔焊的可能，嚴重影響繼電器的使用性能，危害行車安全。為此，本文采用分型接觸理論建立接觸電阻模型，綜合考慮觸點間接觸力、接觸面積及材料的比熱容、導熱系數等，建立了繼電器觸點閉合瞬間大電流作用下的有限元模型，模擬計算觸點間的電勢分布及電流密度為后續接觸間焦耳熱計算奠定基礎。

關鍵詞：繼電器 接觸電阻 瞬態接觸 電場

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