H∞ Robust Controller Design for an Induction Generator Driven by a Variable-Speed Wind Turbine

Abstract

This paper presents the modeling and robust controller design design for a wind-driven induction generator system. a  robust controller for the static synchronous compensator (STATCOM) and the variable blade pitch in a wind energy conversion system (WECS) is designed to be controlled voltage and mechanical power. This controller leading to satisfactory damping characteristics achieved for the closed loop system. Effects of various system disturbances on the dynamic performance have been simulated, and the results comparison with output feedback controller reveal that the proposed controller is effective in regulating the load voltage and stabilizing the generator rotating speed for WECS. The nonlinear simulation was conducted and that comparison with the above linear simulation shows that the simulations carried out for small changes in system inputs is sufficiently accurate. For review performance against large disturbances from a symmetrical three-phase short circuit at infinity bus bar has been used  and the results show robust controller design as well as fluctuations resulting from the short circuit is damped.