Review on transient stability prediction methods based on real time wide-area phasor measurements

With the wide application of PMU in power system, the real time prediction and emergency control of power system transient instability using the wide-area measurements has brought wide attention. There are two sub-problems: the postfault rotor-angle trajectory prediction and the real time transient instability detection. There are three categories for the former sub-problem. They are the network reduction based rotor-angle trajectory super-real time simulation, the curve-fitting based trajectory extrapolation and the angle speed prediction and integration methods. The curve-fitting based trajectory extrapolation includes the polynomial function, the auto regression model and the trigonometric function model. There are three types of criteria for the transient instability detection. They are the threshold-type criteria, the differentiation-type criteria and the integration-type criteria. The threshold-type criteria include the rotor angle threshold and the angle speed threshold and the post-fault voltage trajectory based criteria. The differentiation-type criteria include the trajectory concave and convex characteristics based criterion and the instability criterion based on the variation rate of energy function. The integration-type criterion mainly is the EEAC theory based instability criterion. A comprehensive comparison, analysis and reviews of the fundamental properties of these methods are presented in this paper.