Design of robust coordinated SVC supplementary controllers

A method for designing coordinated H_∞ SVC supplementary controllers is presented to improve the damping of interarea oscillations. A distributed controllers are designed considering overvoltage problem, which is thought to be a critical issue for SVC to design a supplementary damping controller. The proposed method contains a method to obtain dynamic equivalents of a power system model through an uncertainty minimization procedure. This method is aimed for realizing a tight design for distributed controllers so that a better performance of the total system can be gained. In addition, an uncertainty minimization process is used to regulate indirectly the controller's output so that the overvoltage problem is treated in the design step. The locations of SVCs are determined from the voltage stability point of view using bus participation factor. An effective input to damp oscillations is selected based on residue concept. The effectiveness of the proposed control design is demonstrated through nonlinear numerical simulations in five machine eight bus system under several critical operating conditions.