Analysis of average-closing-speed for medium-vacuum circuit breaker from theoretical calculation aspects

Abstract

Average closing speed is an important indicator for evaluating the performance of CB, in order to calculate the average closing speed of the spring operating mechanism of the medium voltage vacuum circuit breaker, the paper establishes a simplified model of CB mechanism, combined with the kinetic energy theorem, and obtains the average closing speed by analyzing the equivalent mass and energy of the mechanism. In order to verify the correctness of the proposed method, the paper establishes a CB simulation model to obtain the simulated average closing speed. In the calculation of the energy of the open-off phase, the paper adopts a segmentation calculation method, which divides the closing process into the open-distance phase and the over-travel phase, and the calculated average closing speed is more accurate. This theoretical calculation method provides a theoretical basis for the research and development of the medium-voltage vacuum CB spring operating mechanism, and plays a positive role in related research and development work.