Fault-tolerant control in variable speed drives: a survey

A survey on fault-tolerant control is presented for variable speed drives (VSD), mainly addressing DC and induction motors. Thus, fault diagnosis, accommodation and hardware reconfiguration are reviewed with application to VSD. First, the most common fault scenarios in these electrical machines are described. These conditions are analysed, and their implications and mathematical modelling are discussed. Next, the fault diagnosis strategies based on signal processing, model-based techniques and artificial intelligence are reviewed. Moreover, the diverse hardware reconfiguration schemes of power actuators with semiconductor failures are detailed. A key piece in any VSD is the control algorithm, which can be severely affected in a fault condition. Finally, the fault accommodation schemes suggested so far in the literature are illustrated.