Demagnetization Fault Diagnosis in BLDC Motor Using Low-Cost Hall Effect Sensors

摘要

This paper proposes a demagnetization fault diagnostic method for a brushless direct current (BLDC) motor using Hall effect (HE) sensor sequence. The low-cost Hall effect sensors positioned 120° apart are used on the stator of a BLDC motor in order to monitor the change in the sequence during demagnetization fault conditions. Demagnetization effect in the permanent magnets (PMs) can be due to various causes;however, the broken PM defects are taken in our study. In contrary to the healthy operation of the motor, the significant change observed in the Hall sequence pattern during the demagnetization fault conditions is used as the fault signatures in this study. The change in machine quantities in terms of phase currents and magnetic flux density (B_M) characteristics is investigated numerically through a developed co-simulation model of a BLDC motor with the Simplorcr drive circuit in Maxwell 2D tool. The numerically obtained results are validated experimentally, and the change in Hall sequence signals is investigated in order to detect, diagnose and identify the demagnetization fault in the BLDC motor. The diagnosis of the broken PM demagnetization fault using the low-cost Hall sensor's sequence is the novel contribution to this work.