The Ultra-High Voltage (UHV) Circuit Breaker (CB) is a protective device that applies power to the power system through opening and closing operations and ensures the stability of the system by blocking fault currents caused by ground, short, and other accidents. When UHV CB perform the closing and opening operations, gas flow affects not only interrupting performance of the interrupter but also dynamic behavior of the driving part. Therefore the gas flow should be considered to get more accurate solutions of the dynamic analysis in the CB.
In this study, the fully coupled method between the fluid and multi-body dynamics analysis was developed in order to overcome those problems of the decoupled method. And a co-simulation program coupling the fluid dynamics program and multi-body dynamics program for UHV-CB was developed. The developed co-simulation program was applied to a product to verify the method and the program. The verified results show a good agreement between the simulations and experiments.