Diode rectifier bridge-based structure for DFIG-based wind turbine

This paper proposes a new structure for the doubly-fed induction generator (DFIG)-based wind turbine. The proposed structure consists of a DFIG controlled by a partial rated power converter in the rotor side, a three-phase diode rectifier bridge (DRB) connected to the stator, and a DC/AC full rated power inverter. As this structure could isolate the DFIG and the grid by a DC-link, the DFIG could avoid the direct influences from the grid, and achieve fault ride through requirement easily. Based on this structure, two control strategies are developed to control the DFIG and fulfill maximum power output. The simulation results based a MATALAB/Simulink using a 2MW DFIG compare the performances of DFIG system with the two control strategies. Further, the experimental results based on a scaled-down setup with a 7.5kW DFIG validate the correctness of the control strategies.