Type E Fault Performance Improvement of DFIG Using Lookup Table-Based Control Scheme

Abstract

The low and high voltage grid faults are to be taken seriously because of low converter ratings of doubly fed induction generator (DFIG). During low voltage fault, using the developed technique, the rotor flux reference value transforms to a new value from synchronous speed to a lesser value or even to zero based on the decrease in the stator voltage. This reference speed increases in case of high voltage faults. This changing in speed is for injecting rotor current at a rotor slip frequency based on the change in speed of rotor during the fault. So, the stator flux DC-offset component is mitigated and making it decomposes quickly by controlling the deviation of rotor speed from a reference value with controlled flux decomposition. The torque ripples, current surges, and overall system performance are improved when the system is analyzed for 50 and 130% of the rated voltage under fault. The system is studied under simulation using MATLAB/Simulink software.