Hybrid Controller for Variable Speed Wind Energy Conversion System with Slip Energy Recovery Using Matrix Converter Topology

Abstract

This paper presents an improved control method of variable speed Wind Energy Conversion System (WECS). The power conversion chain uses Doubly Fed Induction Generator (DFIG) supplied via Matrix Converter (MC) to ensure reliability and good energy conversion management. The proposed hybrid control method combines the merits of Sliding Mode Control (SMC) in term of robustness and high dynamic response in transients to those of Proportional Integral (PI) regulators in term of stability in steady state for constant references. The designed method uses a Fuzzy Logic Supervisor (FLS) that can switches between the two modes according to desired performance. The proposed hybrid controller is applied as a Maximum Power Point Tracker (MPPT) for two wind speed profiles, the first changes abruptly, and here we had take into account the low frequency component of the wind speed model, and the second profile take the complete wind speed model (low and high frequency components). The purpose of using two wind profile is to depict the advantages and disadvantageous of each control mode. The proposed control method provides best efficiency of the conversion chain especially for medium and high power generation systems, also, very attractive results in term of reference tracking and oscillations around Optimal Power Points (OPP) are achieved providing quick and smooth energy conversion. In addition, a unified power factor and low harmonic distortion are also achieved in the grid side.