| The first decades of this century, there is an increasing development for the electrical power system. And the power system will face the great challenges. High voltage SF6 circuit breaker has been considered as the important electrical equipment. The investigation of its key technology covers several subjects, such as electromagnetic, heat and mechanical fields. Focus on it to have theoretical study will have realistic significance for increasing the design level of switch industry.Based on large number of the domestic and overseas references, this thesis concludes the research contributions of many experts and scholars, the current hot problems, combining the developing demand for high voltage SF6 circuit breaker, some key technical problems have been studied.3D electric field simulation of high voltage SF6 circuit breaker and numerical computation method. Firstly, the numerical computation techniques have been discussed in this thesis. Insulation performance analysis is the basic and key process for high voltage SF6 circuit breaker and other GIS, so numerical computation of electrics field plays very important role. For high voltage SF6 circuit breaker with multi-dielectric media and complex structure, it's the key for solving the problem by establishing suitable mathematical model, applying the numerical computation methods with high precision and efficiency, In this thesis, based on the analysis of characteristics of common numerical computation methods and aiming at the real structure of the SF6 circuit breaker products, conventional charge simulation method has been applied to analyze the 3D electric field. Taking the nozzle, parallel capacitor and shading cover into consideration in the calculation. Based on it, for solving disadvantage of contrived interfere of the conventional charge simulation method, it's the first time to propose the optimization charge simulation method in this thesis, and numerical computation for the demonstrated example have been achieved to verify the feasibility and validity. Furthermore, a novel combined finite element method and charge simulation method has been proposed in this thesis for realizing the electric field computation of open boundary problem.Modeling of dynamic electric arc and analyzing on the electric arc dynamic characteristics during the interrupting process. It's key problem for establishing the precise electric arc dynamic model and studying the dielectric recovery characteristics and interrupting performance. This thesis proposed the 2D dynamic arc model by using the equivalent element method and physical and mathematical model coupling with gas flow field. Numerical computation of the dynamic variation of the arc have been completed in the process of before current zero, after current zero and approaching zero to simulate the arc dynamic variation during the interruption process for the high voltage SF6 circuit breaker.Investigation on the gas flow field with viscous, active, stride-sonic, compressible for high voltage SFs circuit breaker. An improved finite volume technique and total variation diminish scheme has been presented for solving the numerical problem with complex flow gas and space time processing synchronously, based on analysis of some numerical method for increasing the convergence, precise and strong capture capacity of shock wave. And based on the simulation of dynamic arc characteristics during the interrupting process, the interactive mechanism of the arc and high velocity gas flow has been deeply analyzed, the variation of the gas flow parameters under the condition of arc clogging and interaction of arc and shock wave have been studied. A theoretical basis has been provided for improving the dielectric recoverycharacteristics of high voltage circuit breaker.Optimization of the nozzle based on the computation of inverse problem of electricfield/gas flow field. Based on the calculation of dielectric recovery characteristics of different kinds of nozzle, the optimization scheme of nozzle has been proposed i...
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