Predictive current control of a wind energy conversion system based DFIG via direct matrix converter

Abstract

The paper presents a predictive direct power control of a Doubly Fed Induction Generator (DFIG) via a Direct Matrix Converter (DMC) for use in variable speed Wind Energy Conversion System (WECS). The proposed control method combines the merits of Finite States Model Predictive Control (FSMPC) in term of flexibility to the ones of DFIG control in term of maximum power extraction over a large range of wind speeds. The proposed control algorithm selects the switching state of the Direct Matrix Converter (DMC) that minimizes the error between rotor currents predictions to their computed values for all different voltage vectors. The optimal voltage vector that minimizes a cost function is then applied to the DFIG rotor terminal. Moreover, the proposed predictive control is easily extended to minimize the stator and rotor reactive power with unity power factor operation. Simulation results show that the proposed control method is intuitive since it is simple, multi-objective, avoids inner loops and provides best dynamic performance.