Design of Rotor-side Controller Using Adaptive Time-frequency Method for DFIG Bearing Fault Detection

To ensure the reliable operation and power quality of wind power systems, the fault-tolerant control for DFIG is studied in this paper. Based on measured motor currents data, an adaptive statistical time-frequency method is then used to detect the fault occurrence in the system and then let the controller compensate for faulty conditions. The feature vectors including frequency components located in the neighborhood of the characteristic fault frequencies is first extracted and then used to estimate the next sampling stator side current in order to better perform the current control. Therefore, with early fault detection, isolation and successful reconfiguration would very beneficial in wind energy conversion system. The feasibility of this fault-tolerant controller has been proven by means of mathematical model and digital simulations based on Matlab/Simulink. The simulation results of the generator output show the effectiveness of this proposed fault-tolerant controller.