An Online Optimization Algorithm for Alleviating Contingencies in Meshed Networks

摘要

Power systems are increasingly operated in corrective rather than preventivesecurity mode, which means that appropriate control actions must be takenimmediately after a contingency has occurred. This paper proposes an on-linealgorithm for automatically alleviating contingencies such as voltage limitviolations and line overloads. Unlike previously proposed approaches, thenetwork itself serves as a natural solver of the power flow equations. Thismakes it possible to start the implementation immediately and avoids problemscaused by modeling errors. Every time the controller receives measurements fromthe grid, it evaluates the presence of contingencies, and computes the optimalcorrective actions that can be implemented before the next sampling period,subject to ramping constraints of the generators. These corrective actions areimplemented through the standard Automatic Generation Control. Finding theoptimal incremental corrective actions is fast because this problem islinearized. The effectiveness of this algorithm at correcting both lineoverloads and voltage violations is demonstrated using the IEEE-118 Bus testsystem.