Numerical Simulation Of The Dynamic Evolution Of High Voltage SF₆ Circuit Breaker

In recent years, with the rapid development of Chinese electric power system industry, there is a rapid development trend in high voltage electrical apparatus industry. High voltage SF6 circuit breaker occupies an important place in the power system, especially in ultra-high pressure and extra-high pressure field developed recently.Therefore, the performance of high voltage SF & circuit breaker is put forward to higher request, which makes the breaker developing to the higher voltage level and larger capacity direction.In this paper, it is known that the factors affecting the variation of arc and evolution process of arc in the process between breaking and opening of high voltage SF6 circuit breaker by researching on its process between breaking and opening.Various influencing factors of the breaker are optimized in practical design to improving the performance of high voltage SF6 circuit breaker.Along with the computer technology and computational fluid dynamics theory developed vigorously, the new numerical simulation method is applied to the research on high voltage SF6 circuit breaker. There are more advantages of numerical simulation which is compared with the traditional research methods, such as less time, less cost. and more convenient and flexible.Meanwhile, the phenomenon of study can be observed more intuitively and the optimum operating state of the breaker can be achieved by revising the parameters, so as to guide production application in operation. So, the numerical simulation method has been applied to the study of high voltage SF & circuit breaker.It was primarily researched in this paper that the key technology of effecting the performance of high voltage SF6 circuit breaker, which is the evolutionary process of arc in the arc extinguishing chamber with opening the circuit breaker. Firstly, according to the actual structure of high voltage SF6 circuit breaker, the simulation process of its arc extinguishing chamber is pre-treated in COMSOL.The pre-treatment includes that geometry modeling, mesh generation, material definition, and physical field selection modeling.Then, the mathematical model of the breaker arc extinguishing chamber is built.Secondly the simulation model is solved by using the finite element method. Finally, the simulation results are visual post-trested by using the model of post-treatment in COMSOL, so that the simulation data is more intuitive.Through the simulation on the dynamic evolution process of arc in the arc extinguishing chamber of high voltage SF6 circuit breaker in this paper, it is obtained that distributed diagram of electric field and ion concentration of arc in the chamber when the moving and static contacts in different stroke.there is a stronger appreciation of dynamic change of arc in the opening or breaking process of high voltage SF6 circuit breaker by analyzing the results. That has a positive significance to improve the performance of high voltage SF6 circuit breaker and make the breaker developing to high voltage, large capacity, intelligent, modular, and miniaturization.