1. College of Electrical Engineering, Shanghai University of Electric Power, Shanghai 200090, China; 2. Shanghai Donghai Wind Power Co. Ltd., Shanghai 200433, China
Owing to the harsh marine environment, the stator winding short-circuit faults of offshore doubly-fed induction generator(DFIG)occurr constantly. Due to the low accessibility, the problems of hard maintenance and high outage loss in the offshore wind farm make the fault-tolerant technology requirements increasingly urgent. The precise and generic stator winding turn-to-turn short-circuit model of DFIG is built based on the short-circuit fault characteristics of DFIG stator windings. To solve the problem of the operation for DFIG which is seriously affected by the increase of stator negative sequence current during the fault of sequence current is seperated and the negative sequence current is extracted and offsetted by injecting the corresponding harmonic voltage into the rotor side, and the negative sequence controller is built to restrain the negative component of the stator phase current after the fault. The simulation and experimental results indicate that the proposed method is able to reduce the amplitude of stator negative sequence current and pulsation of output power.
WEI Shurong, WU Rui, FU Yang,et al.Feasibility Analysis of Fault-tolerant Technology for Stator Winding Turn-to-turn Short-circuit Fault of Offshore Doubly-fed Induction Generator[J].Automation of Electric Power Systems,2019,43(5):114-120.DOI:10.7500/AEPS20180328005Copy