涡流对断路器方形永磁机构特性的影响

Effect of eddy current on characteristics of square permanent magnetic actuator of circuit breaker

由于高压断路器永磁机构工作时间短、动作速度快,工作时会在动静铁芯中产生涡流,为了分析其对机构特性的影响,采用耦合法对永磁机构的瞬态磁场进行分析,并研究了电压激励下的瞬态磁场,推导出考虑涡流影响的非线性瞬态磁场数学模型.运用有限元分析软件Ansoft对方形永磁机构进行仿真,分析涡流对其特性的影响,并对其损耗进行计算分析.分析结果表明,由于涡流的影响使永磁机构的动作时间增长,在永磁机构动作过程中,动铁芯的涡流损耗很大.

Due to the short working period and high action speed, the permanent magnetic actuator of high voltage circuit breaker will generate the eddy current in both dynamic and static iron core during working. In order to analyze its influence on the characteristics of actuator, the transient magnetic field of permanent magnetic actuator was analyzed with the coupling method, the transient magnetic field driven by voltage was studied, and the mathematical model for the nonlinear transient magnetic field was derived with considering the effect of eddy current. The square permanent magnetic actuator was simulated with Ansoft finite element software. The influence of eddy current on the characteristics of permanent magnetic actuator was analyzed, and the loss of actuator was calculated and analyzed. The analysis results show that the action time of permanent magnetic actuator will increase due to the effect of eddy current. In the action process of permanent magnetic actuator, the eddy current loss of dynamic iron core is quite large.