小规格双断点塑壳断路器短路分断性能研究

Study on Short Circuit Breaking Capacity of Small Size Two-Breakers Moulded Case Circuit Breaker

在小规格双断点塑壳断路器的设计中,为了实现过载和瞬动特性,使用直热双金螺线管电磁铁式脱扣器,但脱扣器的结构能够承受的能量也会因此降低。采用增加内阻的方法,可以将短路分断的电流和能量降低,在小规格电流段实现高短路分断能力。

In order to achieve overload and instantaneous characteristics,the small size two-breakers moulded case circuit breaker(MCCB)uses the direct heating bimetal sheet and solenoid electromagnet release device,but the structure of the release device can withstand less energy.By increasing the internal resistance,the current and energy of short circuit breaking can be reduced,and the high short circuit breaking capacity can be realized in the small size section.