Design and Optimization of High-Performance Rare-Earth Free Interior Permanent Magnet Motors for Electric Vehicles Enabled by Iron Nitride Magnets

Electrification initiative in ground transportation applications is necessary to minimize CO
2
emissions. However, this initiative is accompanied with technical challenges at the motor level. Current motor technology employs rare-earth metals in Permanent Magnet (PM) which introduces sustainable supply risks to Electric Vehicles (EV) makers. In this paper, a new rare-earth free PM material that is currently under development, namely, Iron Nitride (FeN) manufactured by Niron Magnetics will show the potential to replace rare-earth PM material while achieving the same performance levels. The FeN PM targets an energy product ranging from 24 to 36 MGOe. Furthermore, commercially available high-performance Ferrite by Hitachi will be blended with FeN PM with both energy products. The proposed motors use Chevrolet Bolt motor that employs Dysprosium-Neodymium Iron Boron (Dy-NdFeB) PM as a baseline design. Moreover, genetic algorithm optimization, detailed demagnetization analysis, efficiency maps, and rotor stress mechanical analyses will be provided.