电容器组投切用SF_6断路器介质恢复特性数值计算与试验研究

The Numerical Computation and Experiment Research on Dielectric Recovery Characteristics of SF_6 Circuit Breaker for Switching Capacitor Bank

针对126 k V电容器组专用SF6断路器介质恢复特性进行数值计算与试验研究。对断路器灭弧室电场和气流场进行数值计算,依据流注理论,得到断路器触头间击穿电压曲线;搭建试验回路对断路器触头间隙动态击穿特性进行试验,测量断路器合闸和分闸过程中的击穿电压;结合数值计算与试验结果,分析不同压强对断路器合、分闸过程击穿电压的影响,给出高压SF6断路器介质恢复特性的变化规律。研究结果表明:对于同样的触头间隙,合闸过程(平均速度4.7 m/s)击穿电压大于分闸过程(平均速度9.6 m/s)。

The dielectric recovery characteristics of the capacitor bank SF6 circuit breaker is studied through numerical computation and experiment. The electric field and the flow field of the arc quenching chamber is calculated, and then the breakdown voltage curve between contacts can be obtained based on the stream theory. The experimental circuit is set up for the experiment of gap dynamic breakdown characteristics between arc contacts,and the breakdown voltage is measured during the closing and breaking process of the circuit breaker. The numerical and experimental results are then combined to acquire the dielectric recovery characteristics of the SF6 circuit breaker by analyzing the influence of different pressure on the breakdown voltage between contacts. The results show that the breakdown voltage of the closing process（ with 4. 7 m / s average speed） is greater than that of the breaking process（ with 9. 6 m / s average speed） for the same contact gap.