Switching Fault-Tolerant Control for DFIG-Based Wind Turbines with Rotor and Stator Current Sensor Faults

Abstract

This paper presents a switching fault-tolerant control (SFTC) strategy for a doubly-fed induction generator-based wind turbine (DFIG-WT) subject to rotor and stator current sensor faults. A novel stator-current-loop vector control scheme is proposed for the regulation of DFIG-WT without involving rotor currents, and it is compared with the conventional rotor-current-loop vector control scheme on closed-loop stability, tracking performance, and robustness against model uncertainties and external disturbances through theoretical analysis. The SFTC strategy switches between the rotor and stator current vector controllers via a switching logic based on Kalman filter-based fault detection and isolation (FDI) scheme. The proposed SFTC strategy is able to provide superb transient and steady-state performance, strong robustness to parameter uncertainties, and high fault-tolerance capability under rotor and stator current sensor faults. Simulation studies verify the control performance of the SFTC strategy.