Application of linear quadratic regulator to control directly power for DFIG wind turbine

Abstract

This paper designs a new control law to control directly the power output of a doubly fed induction generator wind turbine. The proposed control law is based on Linear Quadratic Regulation for both grid side and rotor side converter; the rotor side converter's controller is to get the maximum power output of the wind turbine and reference reactive power in the stator winding side while the grid side converter's controller aims to remain a constant voltage on the DC link and a constant reactive power output in the grid side converter. The proposed method is evaluated by simulating a 1.5-MW doubly fed induction generator wind turbine in MATLAB/Simulink environment. From simulation results, we can be seen that by using the suggested controllers, the errors between the reference values and actual values are smaller than that of a proportional-integral controller. Therefore, the doubly fed induction generator wind turbine with proposed controllers has a good performance.