Fuzzy Logic for Improving DTC and DPC Controls in WECS Based on Doubly-Fed Induction Generator

This paper provides a performance enhancement for direct torque control (DTC) and direct power control (DPC) applied to two-level back-to-back converter feeding the rotor of doubly fed induction generator (DFIG) powered by random speed wind turbine (WT). For this purpose, the sector number in the DTC and DPC is extended from 6 to 12 sectors. While, the switching table based on hysteresis controllers are replaced by fuzzy logic controller (FLC) in both DTC and DPC control. The designed fuzzy 12 sectors DTC (F12S-DTC) and fuzzy 12 sectors DPC (F12S-DPC) significantly reduce ripples in the system under consideration, thanks to error-level consideration and precise localization of the rotor flux vector. The simulation results obtained with the proposed control structure show satisfactory improvements in terms of torque/flux and GSC active/reactive power ripples reduction.