Dynamic characteristic analysis of irreversible demagnetization in SPM- and IPM- type BLDC motors

In this study, we developed an algorithm for the dynamic characteristic analysis of irreversible demagnetization. The conventional static characteristic analysis of irreversible demagnetization considers only d-axis magnetic flux components. However, the accuracy of this method is limited in its analysis of irreversible demagnetization characteristics when the motor is actually rotating. Therefore, we have developed a dynamic characteristic analysis algorithm for irreversible demagnetization. Using the developed algorithm, we compared static and dynamic characteristic analyses results of irreversible demagnetization for interior and surface type permanent magnets. Finally, this study will be helpful for developing robust designs of motors to avoid irreversible demagnetization faults.