Improvements of an IG Wind Turbine System with Constant Switching Frequency Power Control for Microgrid Applications

This paper introduces a novel approach for the fixed-switching frequency of a wind turbine-based induction generator in microgrid. The proposed strategy combines power control and modulated hysteresis control current. One of the advantages of this method is the constant switching frequency of the converter switches, which eliminates a major drawback of the classical hysteresis control. This approach also allows to obtain an AC current with sinusoidal forms and a constant frequency while ensuring minimal total harmonic distortion (THD) of the current. Simulations were conducted using Matlab/Simulink, and the results demonstrated considerable improvements with regard to the classical method, including reduced current THD supplied to the AC grid, and, improved dynamic response performance as well.