Stress analysis of a circuit breaker switchgear mechanism by using multi body dynamics

Abstract

Although a large number of mechanisms like valve opening mechanism, satellite deployment mechanisms have been analyzed by earlier investigators, the fast acting switchgear spring operated mechanisms do not appear to have been investigated using flexible multi body dynamic analysis methodology. This paper presents the analysis of switchgear mechanism used for 69 kV-SF6 circuit breaker. As time of operation of this mechanism is very short (0.07 s), the members of the mechanism are required to be considered as flexible for analyses. A scaled down 1:2 model of the switchgear mechanism to perform its open operation has been fabricated for the purpose of this analysis. The dynamic response of this spring operated switchgear mechanism during opening operation has been carried out by using equations of motion with the help of MATLAB. The stress analysis of this mechanism is carried out by using MBD analysis software (Adams). The results obtained by using the members of the mechanism as rigid in the theoretical equations method and the flexible multi body dynamic method in which the members are treated as flexible are compared and presented.