A Fault Diagnosis Method for Current Sensor of Doubly Salient Electromagnetic Motor

This article proposes a fault diagnosis method for current sensor in doubly salient electromagnetic motor (DSEM) drive system with two current sensors, which can distinguish gain fault and zero-offset fault. First, it wraps the armature winding and the excitation winding around the current sensor by changing the placement of current sensor. Then, fault location is realized by detecting the characteristics of the constructed phase current. Second, a three-step method is proposed to distinguish gain fault and zero-offset fault for current sensor. And the output current of a faulty current sensor is compensated to realize fault-tolerant operation for the drive system. The proposed method can distinguish gain fault and zero-offset fault, which does not require additional diagnostic costs and is not affected by the motor nonlinear model. Finally, the experiments on a 12/8-pole DSEM validate the correctness and feasibility of the proposed method.