Minimization of powers ripple of direct power controlled DFIG by fuzzy controller and improved discrete space vector modulation

Abstract

This paper presents a new direct power control (DPC) strategy for a double fed induction generator (DFIG) based wind energy generation system. The strategy of the discrete space vector modulation (DSVM) that is on the basis of the DPC, is implemented. The algorithm to select voltage vector can effectively change the response of the system. So, a new analysis is done and a new switching table is proposed. The proposed switching table is presented to optimize the performance of the voltage vectors by accurately designing the sequence of the voltage vectors. Rearranging the sequence of the voltage space vectors has an influence on active power ripple. To enhance the performance of the closed loop system, fuzzy system is proposed in place of the switching table and hysteresis system. The four variables, rotor speed, errors of the active and reactive powers and stator flux position are exerted to the fuzzy system and the output is the vector that should be implemented to the switching devices. The outperformance of the proposed method is demonstrated by performing simulations in Matlab Software.