Power system restoration dynamics issues

Recognizing that power system blackouts are likely to occur, it is prudent to consider the necessary measures that reduce their extent, intensity and duration. Immediately after a major disturbance, the power systempsilas frequency rise and decay are arrested automatically by various control and protection schemes. The success rate of these automatic mechanisms has been about 50%! The challenge is to coordinate the control and protective mechanisms with the operation of the generating plants and the electrical system. During the subsequent restoration phases, plant operators in coordination with system operators attempt to manually maintain a real and reactive balance. The duration of these manual procedures has invariably been much longer than equipment limitations can accommodate. In this paper several restoration dynamic phenomena are presented and the required research and development identified.