Improved Fault Ride Through Strategy Of Doubly Fed Induction Generator based Wind Turbine Using Model Predictive Control

Doubly-fed induction generators (DFIGs) are broadly used in wind power plants owing to their benefits. However, Due to its direct connection to the grid, the DFIG is vulnerable to external disturbances. Current grid codes require DFIG to maintain its connection to the network and deliver reactive power during grid disturbances. This paper presents an enhanced fault ride-through (FRT) approach of the DFIG to meet grid connection requirements. The proposed method uses model-based predictive control (MPC). Resistors located in series with the rotor serve to decrease the rotor overcurrent during deep voltage sags. This method improves the transitional states of the system under fault conditions and decreases fault negative results, including DC link overvoltage, rotor overcurrent, and electromagnetic torque oscillations, and also helps grid voltage restoration by delivering reactive power to the grid. Therefore, the FRT regulations of the recent grid codes can be satisfied by using this method. Simulation analyses are conducted using MATLAB/SIMULINK on the DFIG-based wind turbines to evaluate the efficiency of the proposed strategy.