Study On System Of Finite Element Analyses Of Electric Field And Optimization Design For Circuit Breaker

In the electrical power system, the medium voltage and high voltage circuit breakers (CBs) are vital control and protection electrical apparatus. And the key technology problem of the CBs, the numerical computation and optimization of electric field for the CBs has been investigated in this thesis. The combined system of the electric field calculator and optimization design for CB based on the interactive technology and regional identification has been developed, and finite element method (FEM) has been applied as the numerical computation tool. And the system covers several major functions, such as, the preprocessing subsystems, the numerical calculator of electric field, post-processing visualization module and optimal design module for circuit breakers. Accordingly, the traditional design strategy of the CB, that is, "Experienced design-Tests-Redesign-Retest" has been thoroughly changed. Moreover, the combination of finite element analyses and optimization system has been proposed for effectively solving the numerical simulation and inverse computation for the CBs. And the R&D basis for investigating the insulation performance of SF6 arc-quenching chamber and vacuum interrupter has been provided.The preprocessing module of the proposed system includes the following functions, such as, geometrical modeling, meshing grid generating and physical modeling. And the mathematic modeling with interactive technology and regional identification has been developed. Besides the automatic densifying and adjusting of the meshing grid based on the variation of the electric field strength and equal-potential has be performed successfully. The efficiency of the numerical computation of the electric field has been improved. And for the CBS, the basis for realizing computer aided simulation and analyses of electric field with high accuracy have been provided.The established preprocessing module also can realize the computation of the electric field with multi-dielectrics and complex structure. Moreover, the post-processing visualization module has been established, and OpenGL is introduced to visualize the numerical simulation results. Furthermore, the visualization module can effectively execute the combinationinformation of dynamic link database, text documentation and database. The efficiency of data management can be clearly improved. Finally, the optimal design of CB based on the inverse computation of the electric field using genetic algorithm has been accomplished.From the application of the demonstrated examples, the feasibility and validity of the proposed finite element analyses of electric field and optimum design for circuit breakers have been verified. And the interactive numerical testing system for CB has been provided.