Paper Title
An Optimal Sliding Mode Control for Harmonic Currents Mitigation in Grid System Connected with a Wind Turbine

This paper presents a study of the efficiency of the electrical part of a wind generation system. Two back-to-back PWM voltage-fed inverters connected between the stator and the rotor are used to allow bidirectional power flow. The objective is to respond simultaneously to electric energy requirement and power quality concerns. The presentedwind energy conversion system (WECS) is able to track the maximum power point (MPP) of the wind energy and also reducing harmonic generated by the non-linear load (NLL). To control the power converters, sliding mode control is used in a way the gains values of sliding surface tuned by a Particle Swarm Optimization (PSO) by minimizing a Mean Square Error (MSE), this guarantees a good results for the reason that the selection is not random. Two regulation loops, have been conceived. The first loop, dedicated to the rotor side converter, (RSC) enables a decoupled control of active and reactive powers flows. As well, it permits the cancellation of the most noteworthy harmonics from the utility current. The second loop, devoted to the grid side converter (GSC), makes it possible to regulate the DC-bus voltage shared between the two converters. To demonstrate the performance of previously mentioned WECS we use the model based on SimPower software.The simulation results obtained show the significant improvement that the control strategy acquired. Keywords - Doubly-Fed Induction Generator DFIG; Wind Energy Conversion System;Bidirectional Converter;Particle Swarm Optimization PSO; Sliding Mode Control.