Influence of Electromagnetic Fluctuation on the Behaviors of NI REBCO Racetrack Coils Applied in MW-Class Wind Turbine Generator

摘要

The electromagnetic fluctuation occurred in the HTS stator magnet owing to the alternating magnetic field and its harmonic component of rotor in the synchronous wind turbine generator (SWTG). It is a potential risk results in the quench of HTS stator magnet. To address this problem, we applied a no-insulation (NI) magnet technology to the HTS racetrack coil to inhibit the thermal runaway utilizing its outstanding self-protection characteristic and tolerance of over-current. In this study, we focus on investigating the feasibility of the NI HTS racetrack coil, in the practical application of MW-class SWTG. Hence, first, an electrical and thermal coupling numerical model using partial element equivalent circuit (PEEC) and finite element method (FEM) is established. Based on this model, the influence of electromagnetic fluctuation on the thermal and current behaviors of the NI HTS winding during the operation of STWG, was clarified. Further, the influences of turn-to-turn contact resistance of NI racetrack coil on the quench characteristic under various electromagnetic fluctuations were discussed. According to these results, the relationship between the rotation speed of STWG and the turn-to-turn contact resistance of the NI racetrack coil was estimated.