Optimization of SMES-FCL for Augmenting FRT Performance and Smoothing Output Power of Grid-Connected DFIG Wind Turbine

Fault-ride-through (FRT) performance and output power variation are crucial issues of the grid-connected wind turbine with the doubly fed induction generator (DFIG). To overcome these problems, the optimal parameters tuning of the superconducting magnetic energy storage and the fault-current limiter (SMES-FCL) with the common part of the superconducting coil (SC) is proposed. In addition to the alleviation of the DFIG output power, the SC behaves as the short-circuit current limiter to enhance the FRT capability. The tuning of the SC inductance and the controller parameters of converters is optimally conducted, so that the DFIG terminal voltage deviation and the power fluctuation during faults are at their minimum. By simulation study, the utilized power and energy of the SC for the grid stabilization are curtailed, whereas the dynamic performance of the SMES-FCL is higher than a single SMES unit.