An optimization of superconducting coil installed in an hvdc-wind farm for alleviating power fluctuation and limiting fault current

The vital problems of a high-voltage direct current (HVdc) wind farm are the dc power fluctuation and dc faults. To tackle both problems simultaneously, the superconducting magnetic energy storage with fault current limiting capability (SMES-FCL), which is incorporated into the HVdc-wind farm system, is proposed. The SMES-FCL can be used to lessen the dc power fluctuation due to intermittent wind power and limit the fault current in the dc line. The optimal SMES coil and control parameters are tuned based on minimization of power and voltage fluctuations, and stored energy. Study results elucidate that the optimal SMES-FCL provides higher effect on power smoothing and fault current limiting than the non-optimal SMES-FCL against dc fault and wind power levels.