断路器电弧背后击穿的影响与抑制

Influence and Suppression of Arc Back Breakdown on Circuit Breaker

断路器在短路分断时,有时会出现一种电弧背后击穿现象,这种现象会严重影响断路器的短路分断性能。解释了背后击穿现象发生的原理,分析了影响因素。灭弧室的栅片对电弧背后击穿现象的影响最大,具体影响因素包括灭弧栅片的面积、长度、厚度、数量和位置等。改善产品的灭弧室散热是有效的解决方法,但是在小体积的断路器中,由于没有空间,所以宜用磁吹法、气吹法和内阻法来降低短路分断时背后击穿现象造成的影响。灵活掌握断路器产品体积、成本与短路分断能力之间的关系,有利于快速设计出符合需求的小体积、低成本产品。

When the circuit breaker is in short circuit breaking,sometimes there is an arc back strike phenomenon,which will seriously affect the short circuit breaking performance.The principles of arc back strike is explained,and the influence factors are analyzed.The main factor is arc extinguishing grid.The area,length,thickness,quantity and position of arc extinguishing grids have certain influence.It is an effective solution that improve the heat dissipation of the arc extinguishing chamber.However,in the small size circuit breaker,because there is no enough space,it is appropriate to use magnetic blowing method,gas blowing method and internal resistance method to reduce the impact of back breakdown phenomenon during short circuit breaking.Mastering the relationship between the volume,cost and short-circuit breaking capacity of circuit breakers is conducive to the rapid design of small volume and low-cost products.