On the transmission efficiency of a spring-type operating kinematic mechanism for an SF6 gas-insulated circuit breaker

Abstract

The purpose of this paper is to study the transmission efficiency of a spring-type operating kinematic mechanism for an SF6 gas-insulated circuit breaker. This mechanism has two degrees of freedom, which, when operating in the open, close, or return mode, becomes a single degree of freedom by fixing a link that adjoins the frame to achieve specific requirements. Firstly, the vector-loop method is employed for position analysis of the links of the mechanism. Subsequently, by using coordinate transformation and the geometry of the cam and the follower, the relationships between cam rotation and the position of the linkage follower in the close operation, as well as cam rotation and the position of the motor-switch follower are established. Based on the transmission angle of the linkage and the pressure angle of the cam mechanism, the transmission efficiencies of the mechanism are evaluated and discussed. The mechanism is also computer simulated and the transmission angle is optimized using the augmented Lagrange multiplier (ALM) method. The results show that the optimized parameters noticeably improve the transmission angles of the present design.