Abstract: In order to improve the short-circuit breaking capacity of solid-state circuit breaker（SSCB）in DC

system，a multi-objective optimization method that explores component parameters to achieve optimal breaking

characteristics was proposed. A detailed analysis of the breaking process of the SSCB during a short-circuit fault

was performed，and the influence of the current limiting inductor LB and the voltage limiting capacity factor γ of

the metal oxide varistor（MOV）on the breaking characteristics was investigated by theoretical analysis and

simulation. Based on the breaking characteristics，three optimization objective functions of breaking impact

performance，breaking time and energy absorption were established. The objective functions were optimized by the

multi-objective particle swarm algorithm，and a method which combines technique for order preference by

similarity to ideal solution and decision maker preferences，was used to make decisions. The results show that under

different decision maker preferences，the component parameters LB and γ after the optimization can significantly

improve the breaking performance of the SSCB.

      Key words: low-voltage DC solid-state circuit breaker；topological structure；short-circuit fault；breaking

characteristics；multi-objective optimization