Self-tuning fuzzy PI-based controller of DFIG wind turbine for transient conditions enhancement

Abstract

SUMMARY Satisfactory performance of doubly fed induction generator (DFIG) is indebted to determining the proportional-integral (PI) gains of the power electronic converter controls as accurate as possible to guarantee minimum transients when disturbances occurred in the power system. Since the DFIG is introduced as a dynamical system, PI gains must be changed according to the system requirements. Fuzzy controllers designed based on our best knowledge on the system behavior are able to continuously adjust parameters of the control system to enhance the performance of the system. In this paper, a control scheme based on self-tuning fuzzy PI (STFPI) is proposed to control the power electronic converters of the DFIG. Different arrangements of the STFPI controller are considered in the control scheme of active and reactive power. The performances of the DFIG in three operating modes are compared when the STFPI and the conventional PI are installed and the system experiences a single phase to ground short circuit fault. Super-synchronous, synchronous, and sub-synchronous operating modes are examined in the paper. The idea is implemented on a study system equipped with a DFIG wind turbine, and the obtained results show that when the proposed scheme is employed a superior performance can be achieved in transient conditions and the transients are significantly improved. Copyright © 2014 John Wiley & Sons, Ltd.