Fundamental investigation of a gas circuit breaker in University

Minimizing size of a gas circuit breaker (GCB) and progressing reliability moreover, the fundamental investigation has been needed. In this review, the fundamental investigations of a GCB in Japanese universities were described. In general, a large scale experimental facility is needed for a circuit breaker development. To make experimental facilities minimized, several new approaches were adopted. A MEMS sensor application was aimed for a diagnosis of mechanical failure of a circuit breaker. The mechanical circuit breaker model was constructed to obtain an acceleration characteristic in a mechanical failure mode. A small scale facility made an arcing phenomenon research possible by using the Thomson scattering measurement. An accurate transformer model investigation was focused in a transient analysis. It was found that the transformer impedance had a frequency dependence, which cannot be simulated in the EMTP. © 2010 The Institute of Electrical Engineers of Japan.