Minimal Load Shedding Using the Swing Equation

Abstract

Load shedding constitutes the very last resort for preventing total blackouts and cascading events. Conventional load shedding schemes, which are massively applied in industrial practice, adopt a step-wise approach which usually causes over-shedding or fails to prevent frequency decay above the allowable limits. Recently proposed schemes based on real time intelligent control and neural networks achieve the control objective, but fail to minimize the amount of load to be shed due to the delay incurred in consecutive control decisions. This letter proposes a new load shedding scheme, decoupled from the conventional scheme. This scheme, based on the equivalent swing equation of the system, determines the minimal amount of load that should be shed immediately (in a single step) after the load event/disturbance occurs, in order to guarantee system stability.