Fault Ride-Through Capability Improvement of DFIG-Based Wind Turbine by Employing a Voltage-Compensation-Type Active SFCL

Abstract

Based on the considerations in creating a smart grid roadmap, an integrated application of renewable energy sources and superconducting power devices may bring more positive effects. This paper suggests a voltage-compensation-type active superconducting fault current limiter (SFCL) to enhance the fault ride-through capability of doubly fed induction generator (DFIG) for wind power generation. Since the active SFCL has higher controllability and flexibility than a common resistive- or inductive-type SFCL, its application may give better results. Related theory derivation, cost evaluation, and simulation analysis are conducted, and a comparison between the active SFCL and an inductive SFCL is performed. From the results, the active SFCL can limit the faulty currents flowing through the DFIG’s stator and rotor windings and compensate the generator terminal voltage. The inductive SFCL may not evacuate the surplus active power during the grid fault; however, the active SFCL can smooth the DFIG’s power fluctuation, and the stability of the wind power system can be well strengthened.