All switching operations in power system will cause transient process which propagate in network.Phase-control switching technology of circuit breakers has become an increasingly useful method to mitigate the transient process for a range of specific load cases.Firstly

the domestic and oversea application and the latest development of phase-control circuit breaker are introduced.Then several key problems of phase-control switching

including mechanical characteristic

insulation characteristic of dielectric

precision of controller are presented

and its comprehensive benefit and the development trend are also analyzed.Finally

the necessity and feasibility of popularizing phase-control switching technology in our country are discussed.