Fault-Ride through Improvement of DFIG under Symmetrical/Asymmetrical Voltage Dips

Abstract

In this study, improving fault-ride through capacity of the DFIG under symmetrical and asymmetrical voltage dips has been investigated. Initially, a crowbar protection circuit has been designed for the rotor side converter (RSC). With the help of the crowbar, the fault ride-through (FRT) ability of the wind energy conversion systems (WECS) has been increased, while the capacitors, rotor windings, and converters are protected from critical damage caused by the voltage dip. Then, the crowbar has been equipped with a fuzzy logic controller (FLC) to increase the FRT capacity. The switching time of the crowbar circuit has also been improved to protect the WECS from this serious damage. The suggested WECS has been designed and analyzed in Matlab/Simulink under symmetrical/asymmetrical voltage dips. DC bus voltage, electromagnetic torque, grid currents, crowbar current, and terminal voltage results of DFIG have been obtained. The simulation results of the DFIG have been compared. The results have also been contrasted with related studies. The obtained results demonstrated the robustness, applicability, and dependability of the suggested system.