Optimized design and magneto-thermal coupling simulation analysis of automotive permanent magnet synchronous motor

Abstract This paper presents an optimized design for automotive permanent magnet synchronous motors (PMSM) focusing on expanding their operational speed range and improving efficiency. The issues of high losses and low efficiency in standard built-in fractional-slot PMSMs, which impact the stable operation of vehicle motors, are identified and addressed., Three innovative rotor magnetic circuit structures are proposed utilizing electromagnetic theory and finite element analysis. These designs are simulated and analyzed to reduce overall motor losses to 59% of the original levels and to ensure thermal characteristics meet the demands of wide-speed automotive motors. The study establishes a three-dimensional transient temperature field simulation model to predict temperature rise and distribution across motor components. The optimized rotor structures enhance performance and serve as a reference for future thermal design in PMSMs.