Study on application of new approach of fault current limiters in fault ride through capability improvement of DFIG based wind turbine

Due to salient advantages, Doubly-Fed Induction Generator (DFIG) has more application in power network compared to Fixed Speed Wind Turbine. Because of employing back-to-back converters, one of the important studies regarding new grid code requirements is Fault Ride-Through (FRT) capability of the DFIG. To improve the FRT capability, one of the approaches is Fault Current Limiters (FCLs). In this paper, a new approach of application of the FCLs is studied and its location and impedance type will be discussed. Then, the resistive type of the FCL located in the stator side will be proposed. The proposed FCL can insert a controllable resistance in fault current pass to not only restrict fault current level and compensate voltage sag in the stator but also consume pre-fault output active power of the DFIG regarding wind speed variation. Simulation results and analytics are presented to prove the effectiveness of the operation of proposed approach.