Demagnetisation and Performance Study of Neodymium and Ferrite Assisted SynRM

Paper in proceeding, 2024

This paper focuses on the demagnetisation and performance study of ferrite magnets used in a Permanent Magnet Assisted Synchronous Reluctance Machine (PMaSynRM). The effect of magnetomotive force (MMF) from the stator on the rotor barrier is studied at different current magnitudes and phase advance. The self-demagnetisation of the magnets is also investigated under no-load conditions, and an attempt is made to determine the remanent flux density of different magnets when placed in different rotor barriers together. Lastly, the performance of an optimized ferrite rotor design is compared with an Nd motor of similar volume. To address the performance shortcomings observed when comparing the ferrite motor with the Nd motor of similar volume, a suggested solution involves the development of a hybrid motor incorporating both types of magnets. To match the performance with the Nd motor, the hybrid motor has to be elongated with the same active diameter. This hybrid design yields a weight reduction of 0.9 kg for the Nd magnet while maintaining performance equivalent to that of a Nd motor. Additionally, a substantial cost reduction of approximately 18 % is achieved.