Study On Electro-Dynamic Force Of Apparatus Contacts Based On Finite Element Analysis Of ANSYS

In this paper, contacts parts of current limting circuit breaker and contactor are studied. With 3-D finite element analysis, the current between make contacts, magnetic field around make contacts and electro-dynamic repulsion force acting on the movable contact are analyzed by the finite element simulation software ANSYS. When electro-dynamic repulsion force calculated, the idea of optimization design of peripheral air model is introduced and contacts parts of circuit breaker and bridge contactor are best designed.Through analysis of the current and magnetic field and optimization design of contacts parts, efficiency of contacts parts design are improved. Main studies are as follows:At first, according to 3-D finite element nonlinear analysis , the movable and immovable contacts and arms of current limting circuit breaker and bridge contactor with breakpoint are studied in the static condition. After taking account of the loss magnetic field , infinite element is introduced. The distribution of current, magnetic field and electro-dynamic repulsion force acting on the movable contacts and arms is obtained through the analysis.Secondly, this paper makes analysis of influence on values of electro-dynamic repulsion force exerted by length of conducting spot between contacts and magnitude of peripheral air model. This paper also compares the values obtained from simulation of the finite element method and theoretical formula.Thirdly, this paper takes into account the advantage and disadvantage of electro-dynamic repulsion force acting on contacts parts. After defining values of electro-dynamic repulsion force as objective function , dimensions of contacts parts are optimized in the optimization design module of ANSYS.With rapid development of computer, the technology of finite element simulation is used in more and more modern apparatus designs. In the design of contacts parts, model parameters canbe changed easily and distribution of electro-dynamic repulsion force also can be got accurately by finite element method. During designs, testing expenses may be cut, time of product development cycle may be shortened and benefits can be improved. Therefore the technology of finite element simulation has real significance.