直流混合型限流开关分析与设计

摘要

为研究一种适用于船舶直流电力系统短路保护的限流装置,提出基于斥力开关及快速熔断器的直流混合型限流开关方案.斥力开关在短路发生后迅速分断,电流转移到与开关并联的快速熔断器支路,由快速熔断器完成短路电流的分断和能量的吸收.研制了额定640 V/600 A的原理样机,进行了预期电流峰值为100 kA,时间常数为7 ms的限流分断实验.实验结果表明,斥力开关在短路电流超过设定动作值后200 μs内分断,经过100 μs电流转移到快速熔断器支路,熔断器经过1.1 ms熔断起弧,限流峰值为15.4 kA,故障排除后50 ms限流开关自动重合闸.实验数据验证了理论分析和参数设计的正确性,为该型开关在直流系统中的应用提供了设计依据.%A direct-current (DC) hybrid current-limiting switch topology based on repulsion switch and rapid fuse has been present, which can apply to shipboard electric power system short-circuit protection.The repulsion switch opened the contact rapidly after short circuit; then the fault current was commutated onto the rapid fuse. The rapid fuse broke the fault current and absorbs the energy. A 600 A/640 V DC hybrid current-limiting switch was designed. An experiment with prospective peak current 100 kA and time constant 7ms showed that the repulsion switch opens the contact after the fault current is beyond the set value within 200 us, and the fault current is commutated onto the rapid fuse after 100 us; then the fuse blows out after 1.1 ms. The peak value of short-circuit current is 15.4 kA and the switch recloses after the recovery within 50ms. The theoretical analysis and design of parameters are proved by experimental results. These characteristics are useful for designing the current-limiting switch in DC power systems.