IN H∞ control for STATCOM to improve voltage stability of power system

An innovative nonlinear (IN) H-infinity control for static synchronous compensator (STATCOM) to improve voltage stability of power system is proposed. Taking the parameter deviations, external disturbances and unmodelled dynamics into account, the nonlinear dynamic model of STATCOM can be transformed into a standard Hamiltonian structure with the help of coordinate transformation. Using the Hamiltonian structure of STATCOM, an IN H-infinity control is designed for STATCOM. A two-area four-machine power system is used to testify the robustness and effectiveness of the proposed IN H-infinity control in comparison with the feedback linearisation (FL) control. The numerical simulation results indicate that the IN H-infinity control has better performance than the FL control.