Finite Element Analysis For The Key Parts Of Outdoor Vacuum Circuit Breaker

This paper is finished to research for the key parts of outdoor vacuum circuit breaker. When the influence of vacuum circuit breaker mechanical life factors is considered, some suggestions and conclusions can be got as the finite element analysis for the key parts where the mechanical failure being frequent is finished.First, the development present situation and main structural characteristics for vacuum circuit breaker are reviewed and summarized. Second, the main fault which effects the vacuum circuit breaker reliability and mechanical life is summarized according to the fault data supplied by factory. Then the fault location of the key parts is pointed out on the vacuum circuit breaker which structure is composed of three parts, they are vacuum interrupter, actuator and linkage mechanism. The moving and static contacts, insulating pull rod and mechanism of roller cam are included in these parts. Finally, different finite element methods are used to analyze the main mechanical fault location of these key parts within the different working conditions.During the opening process for vacuum circuit breaker, the thermal stress analysis for moving contact will be carried out as two steps. In the first step, the temperature distribution for contact can be got with the method of heat conduction which is depended on the MSC software. In the second step, the heat stress and deformation can be got by the analysis of thermal stress for the moving contact in the opening process. The collision deformation can be got within the analysis for the closing process of the moving and static contacts where the nonlinear theory is used. The results of the analysis will be compared with the technical requirements to check whether it meets the requirements.The contact analysis is carried out for the cam and roller in the operating mechanism. From this analysis, it can be easily to come to the conclusion that the pressure from the roller is max when the cam is in the opening and energy stored state while the stress is max. The wear position is just the position where the stress is max. The normal stress and deformation for the cam surface can be got in the contact process by the analysis, and then some feasible suggestions can be got through the analysis results.When the deformation analysis for the insulating pull rod is carried out, the method of static analysis can be used to solve the stress distribution and deformation problem, because the rod is made of epoxy resin which can be considered as the elastic material. As the results of the analysis can be got, the insulating pull rod will be checked whether it works safe.The finite element analysis for the three key parts of vacuum circuit breaker is carried out the finite element analysis, in order to validate the design of vacuum circuit breaker in operation are in safe range, if not, some improvement measures will be given.