Assessing online transient stability in energy management systems

An approach that combines automation of table lookup heuristic methods with transient energy function (TEF) methodology and conventional time simulation, taking advantage of the merits of each, is presented. The TEF method, which belongs to the class of direct methods of stability analysis, is described. It can be thought of as a generalization of the conventional equal-area criterion, which applies to first-swing stability analysis of a single-machine-infinite-bus system. It is explained how TEF software could best be used for online transient stability assessment. The process involves the determination of a master contingency list, contingency selection and prescreening, screening using TEF, and determination of safe operating limits.<>