On the design of spring-type mechanism for 69KV SF₆ gas insulated circuit breaker

This paper studies the design of a spring-type mechanism of 69KV SF6 Gas insulated circuit breakers. The creative mechanism design method is first used to synthesize all the feasible mechanisms that satisfy the requirements for the circuit breaker. The kinematics of the mechanisms are then analysed using the vector-loop method. Subsequently, the equations of motions are derived with the Lagrange equation and solved by the 4th order Runge-Kutta method for the dynamic response, which include the position, velocity and acceleration of each machine member. The duration of individual operation, and hence the total duration to complete the full cycle of the mechanism has also been calculated. The time taken for the close, open and return operations are found to be 0.116, 0.076 and 0.069 sec respectively, which are comparable with those obtained experimentally.