SF_6旋弧式断路器似稳吹弧磁场的数值分析

SF_6旋弧式断路器依靠相位上滞后的吹弧磁场对电流产生的电动力,使电弧在SF_6气体中快速旋转而熄灭。这种断路器的灭弧机理与磁场形态有密切关系,吹弧磁场是由通过吹弧线圈的电弧电流与铜套中的涡流共同产生的。本文用数值方法研究这种吹弧装置的似稳态磁场,计算结果与实验数据十分吻合,说明所采用的方法具有满意的精度。通过在不同条件下对吹弧磁场的数值分析,找到了吹弧装置的结构参数和材料性能与磁场的关系,并且还提出了在电弧电流零区获得最大磁场的途径。

A NUMERICAL ANALYSIS OF THE QUASI-STATIONARY MAGNETIC FIELD OF A SF_6 ROTATING ARC CIRCUIT BREAKER

Rotating are SF_6 circuit breaker uses a phase-lagged magnetic field to gener- ate the force upon the are, and the field which is produced by both the arcing current passing through solenoidal winding and induced current in a concentric copper core has a marked influence upon the breaker performance. This paper investigates the magnetic field encountered in such devices. The numerical solu- tion of the two dimensional field equation is presented and compared with experi- mental measurements. The steady state solutions for different conditions are dis- cussed, and the effects of the copper core parameter-thickness and conductivity are revealed. Besides, this paper has proposed an approach. to get the maximum magnetic field in the time zone nearby are current zero.