This study designed an interior permanent-magnet motor combining rare-earth and ferrite magnets with a multi-flux-barrier rotor. Multi-objective optimisation reduced rare-earth magnet use by about 11% and estimated material cost by 7.14%, improving torque-per-cost by 7.43%, while simulations retained back-EMF, torque and efficiency close to the benchmark.
Key findings
- The optimised design used about 11% less rare-earth magnet and cut estimated total material cost by 7.14%, improving torque per cost by 7.43%. Back-EMF and torque remained near benchmark levels, ripple fell slightly and efficiency maps were comparable. Simulated rotor stress stayed below the elastic limit, and both magnet segments resisted demagnetisation under tested conditions.
Why this matters globally
Rare-earth magnets carry price, supply-chain and mining risks. Reducing their use without sacrificing efficiency could improve EV motor affordability and resilience, but global impact depends on manufacturability, reliability and real material prices at scale.
Thai researcher contribution
Khon Kaen University and King Mongkut's Institute of Technology Ladkrabang developed the EV-motor design and optimisation, contributing Thai engineering to a global energy-technology and supply-chain challenge.
Limitations to consider
No physical prototype, dynamometer or vehicle test is reported in the abstract. Material-cost estimates depend on prices and manufacturing assumptions. Assembly tolerances, losses, vibration, noise, thermal behaviour, fatigue life and real drive-cycle control remain to be validated.