New approach to standing phase angle reduction for power system restoration

The paper describes a methodology for the reduction of standing phase angle (SPA) difference between two buses during restoration operations of a power system. These angles may occur across a tie line, between two systems or between two connected subsystems within a system which may causes significant delay in power system restoration. They must be within SPA limits before an attempt is made to close breakers to firm up the bulk power transmission system. To arrive at the desired SPA difference between two buses, the modified contribution at generation/load buses have been evaluated based on sensitivity factors. This methodology acts as a direct help to reduce excessive SPA difference between two buses to an acceptable limit, which otherwise requires regulation of various generation levels on a trial and error basis.