Majlesi Journal of Energy Management Vol. 6, No. 3, September 2017 7 DFIG-Based Wind Turbine System using Four-Level FSVM Strategy 1 elaidi Abdelkader B , 2 oudjema B , Zinelaabidine 1 enbouhenni Habib B 1-National Polytechnique School of Oran Maurice Audin, Oran, Algeria Email: habib0264@gmail.com, belaidiaek@gmail.com 2- Electrical Engineering Departement, Faculty of Technology, Hassiba Benbouali University, Chlef, Algeria. Email: boudjemaa1983@yahoo.fr Received : May 2017 Revised : July 2017 Accepted : August 2017 ABSTRACT: Traditional direct vector command (DVC) structures which include proportional-integral (PI) regulators of a doubly fed induction generator (DFIG) driven have some disadvantages such as parameter tuning complications, mediocre dynamic performances and reduced robustness. Thus, based on analysis of the DFIG model supplied by new modulation technique, this article addresses a four-level space vector modulation (SVM) based on fuzzy logic algorithm (FSVM). The classical DVC command with SVM technique has large ripples on the stator active and stator reactive developed by the DFIG. In order to solve this disadvantage, the DVC command with FSVM technique is proposed. Simulation results show the effectiveness of the proposed command scheme especially in power ripples behavior, reference tracking test and robustness against generator parameters variations. KEYWORDS:Direct Vector Command; Doubly Fed Induction Generator; Space Vector Modulation; Fuzzy Space Vector Modulation; Fuzzy Logic. 1. INTRODUCTION The DFIG is a very interesting solution for variables speed applications such as wind energy conversion systems. The DFIG has several advantages compared to usual induction machine or synchronous generator. However, the DFIG can be controlled from the rotor or stator side by different possible combinations. In [1] vector command (VC) is the most popular technique used in the DFIG based WTSs. The DVC command is simple command and easy implementation. A schematic diagram of WTS with a DFIG controlled by DVC command is shown in Figure.1. In [2], the author has proposed the comparison between the indirect vector command (IVC) and direct vector command for DFIG. In [3], the author has proposed the field oriented command (FOC) for DFIG via hysteresis rotor current controller. In this article, we propose a DVC command to control the stator active and stator reactive power of DFIG based WTS. Since the SVM strategy is usually used in command of AC machine. However, this technique gives more and more THD (total harmonic distortion), and high ripple in stator powers of the DFIG based WTSs. To overcome the drawbacks of classical SVM strategy, a new modulation technique for the inverter command was proposed in this article as fuzzy space vector modulation (FSVM) to command stator reactive and stator active powers. However, this new modulation strategy gives more and more minimum THD value of stator current and power ripples compared to the classical SVM technique. On the other hand, the SVM strategy is complex command and need to calculate the sector and angle. In this paper, we propose a new SVM method based on the calculation of minimum and maximum of three-phase voltage. The advantages of the proposed SVM strategy is not needed to calculate the angle and sector, easy to implement, simple scheme compared to traditional SVM modulation. In this article, we propose DVC scheme based on four- level FSVM (DVC-FSVM) to command the stator powers of a DFIG based WTS compared to the DVC- SVM using four-level inverter.