Model-based fault detection of gain and offset faults in Doubly Fed Induction Generators

Fault tolerance is gaining interest as a means to increase the reliability and availability of distributed energy systems. In this paper, a voltage-oriented doubly-fed induction generator is examined. This work applies formerly developed model based sensor fault tolerant control methods to gain and offset faults. For that reason, saturation is modelled. Fault detection is triggered by residuals. Fault isolation determines the faulty sensor. Replacement signals from observers are used to reconfigure the drive and re-enter closed loop control. While model based FDI for these faults is generally possible, it requires the fault to be large enough to be detectable.