Parity space approach for current sensor fault detection and isolation in electrical systems

The paper deals with faulty current sensor detection and isolation (FDI) in electrical systems. Current sensors are widespread in electrical drives and power converters control. They are used for monitoring or closed loop regulation and performances and robustness of the whole systems depend strongly on their outputs. Thus, a fault occurs on a sensor, fast FDI is required for fast reconfiguration control and then continuous operating. In this paper, a new and fast faulty current sensor detection and isolation is presented. It is derived from space parity approach. Theoretical developments highlights simplifications derived from choosing measurement sampling period much lower than control sampling time. The developed algorithm does not depend on system parameters but only on previous measures, so it can be easily added to any control. Simulation and experimental results demonstrates the effectiveness of the method for a 1 kW induction motor.