新型加铁磁材料触头阴极斑点扩散研究OA

In order to meet the interruption need of vacuum interrupter in the case of minimum arcing time,the simu-lation and experiment methods are used.A kind of contacts with ferromagnetic material is designed firstly in accor-dance with the the theory that the saddle-shaped axial magnetic field is beneficial to the diffusion of vacuum arc.Its axial magnetic field distribution characteristic is obtained though FEM simulation.Then,the diffusion process of the cathode spots between the new type of contacts and the traditional cup-shaped contacts with axial magnetic field is compared by using the power frequency triggered arc test platform.The experimental results show that the speed of the cathode spots of the contacts with ferromagnetic material is reduced when the cathode spots reaches half diameter position of the contact,keeping it relatively and stably burning at the edge of the contact.The density of the cathode spots at the edge of the contact is not much different from the central area and the area covered by the cathode spots is larger than that of the traditional cup-shaped contact.This paper mainly focuses on the arcing process of vacuum arc under partial arcing conditions,especially the initial diffusion stage,which can provide a certain reference for the de-sign of contacts used in vacuum circuit breakers with minimum arcing time.