Analysis of NdFeB Bonded Magnet Behaviors Within High-Frequency Field and High Temperature Using Micromagnetic Simulator

Motors of hybrid vehicles and electric vehicles are anticipated to become smaller and have higher rotational speed. However, the small motors with high rotational speed may demagnetize the permanent magnets of motors by applying a high-frequency field of ~10 kHz at temperatures over 400 K. This demagnetization also depends on a static dc-field ~3-4 kOe. We call this demagnetization phenomena magnetic fatigue. In this paper, magnet behaviors within a high-frequency field and at high temperature were simulated using a micromagnetic simulator.