An algorithm for standing phase angle reduction for power system restoration

During power system restoration, it is necessary to check the phase angle between two buses before closing circuit breakers to connect a line between them. In case of large standing phase angle (SPA) difference the synchrocheck relay does not allow closing of the breaker for this line. Therefore, this SPA has to be reduced before attempting to connect the line. In this paper a new and fast method for reducing SPA is presented. For this purpose, the standing phase angle difference between two specific buses is represented in terms of sensitivity factors associated with the change in real power injections at the buses. The proposed method will act as a direct help for reducing excessive SPA difference between two buses to an acceptable limit.