Coordinated Control of Demagnetizing Method and Inductive SFCL for DFIG Under Symmetrical Faults

摘要

According to grid codes, the doubly fed induction generator (DFIG) based wind turbines should remain connected to the grid and generate additional reactive current during grid faults. However, DFIG is very sensitive to grid disturbances. Demagnetizing method can reduce the rotor voltage, but it requires high demagnetizing current under severe faults. Combining inductive superconducting fault current limiter (SFCL), the required amplitude of demagnetizing current can be reduced. Finally, the required reactive power can be output integrated with TVC control. The simulation results of a 1.5-MW DFIG system validate the theoretical analysis and the feasibility of the proposed control strategy.