A fault tolerant system for current sensors in induction motor drives

In this work, a fault tolerant control system for current sensors in induction motor drives is proposed. The system is composed by two standar control strategies and a bank of observers. The fault detection and isolation is performed by processing residuals generated by the bank of observers. When sensors are healthy, the motor is controlled by a vector control strategy using two current sensors. If a single current sensor fault occurs, the vector control is maintained by replacing the affected information with estimations generated by the bank of observers. If faults occur in both current sensors, a scalar control strategy is used in order to maintain the operation of the drive. The operation of the proposed system is validated by simulation results.