Wide-area coordinating control of SVCs and synchronous generators with signal transmission delay compensation

Wide-area measurements have been proposed to coordinate generator excitations and Static Var Compensator (SVC) auxiliary controls. The wide-area coordinating controller (WACC) utilizes remote signals to compensate the interactions between SVC and generator variables, therefore it provides an additional damping of both local and inter-area oscillations. However time delays introduced by remote measurement and control signals may affect the performance of the controller. This paper focuses on the impact of time delay on power oscillation damping and the application of Smith prediction approach to preserve power system performance with large time delays. Anderson and Farmer four-generator nine-bus power system is used to illustrate delay effect on mode damping and the advantage of delay compensation. Simulation results show that generator speeds and SVC bus voltage oscillations are still well damped for various time delays with the Smith predictor approach.