An Adaptive Predictive Approach to Emergency Frequency Control in Electric Power Systems

Wide-area phasor measurements and modern communication techniques will provide access to system-wide frequency data with high accuracy and small time delay. This will make it possible also to monitor and control also relatively fast phenomena such as frequency instability using centralized approaches. This paper describes the decision logic of a centralized emergency frequency controller based on predictive control. A single machine equivalent for each power system island is computed online using phasor measurements. Using this model the progression of frequency stability after a contingency is monitored and stabilizing load shedding is determined in a coordinated way for the supervised area of the power system.