In the context of global advocacy for green energy

vacuum circuit breakers are considered to be an important technical solution to achieve SF

6

-free high-voltage switchgear

and its mechanical characteristics are the pre-requisite and foundation to achieve electrical performance. Due to the unique performance of vacuum interrupter

the current 126 kV vacuum circuit breaker equipped with spring operating mechanism has problems of not closing to the end during the closing operation. Therefore

in this paper the 126 kV vacuum circuit breaker with CT spring operating mechanism is taken as the research object to perform the output and load matching characteristics analysis and calculation. Based on its matching advantages and disadvantages result

an optimization design method for the cam of the mechanism is described. It is proved by the result of the output and load matching characteristic analysis of the optimized cam that the matching is good and can achieve reliable closing operation. Finally

the feasibility of the optimization scheme is proved through simulation verification and prototype test.