Fast Fault Diagnosis Method for Hall Sensors in Brushless DC Motor Drives

Brushless direct current motors with Hall sensors have been widely used in myriad industrial and commercial applications due to their simplicity and low cost. Meanwhile, the fault tolerant control (FTC) of Hall sensor drives has attracted renewed research attention. During FTC, the motor drives need to diagnose the Hall-sensor fault(s) and reconstruct the faulty signal(s). In this context, we propose an innovative fast fault diagnosis (FFD) method for analyzing different fault cases and diagnosing faulty signal(s) in the shortest possible time. Compared with established fault diagnosis methods, the FFD method does not require complicated vector-tracking observers, and it is capable of handling up to two simultaneous faults while greatly improving the diagnostic speed. Our simulation and experimental results verify the effectiveness of the proposed method and demonstrate its advantages over established methods particularly during transient operations. Due to the simplicity of diagnostic algorithm, the proposed FFD method can be readily implemented in conventional drive systems, either through extra coding within existing controllers or as an auxiliary circuit.