ABSTRACT
To adapt the unmatched reliability of disconnecting switches, a new kind of primary equipment named Disconnecting Circuit Breaker (DCB) is designed and introduced to the grid (Song et al. 2013). The DCB combines the switching and disconnecting functions into one device. The change of design principle has enabled the integration of the disconnecting function with the circuit breaker. Since the primary contact of DCB is in an SF6 protected environment, its disconnecting function is highly reliable. Therefore, the maintenance interval is increased, providing greater overall availability for the substations (Song et al. 2012).
