Torque Density Elevation of Interior PM Synchronous Motor with Minimized Magnet Volume

Permanent magnet synchronous motor (PMSM) has been used to drive a number of vehicles. PMSM has high torque density, high efficiency and wide speed range. However, the high cost of permanent magnets is viewed as a disadvantage. This paper presents a technique that can increase the torque density by modifying the shape of permanent magnets and minimizing the magnet volume. Models were compared by increasing the thickness and the width of permanent magnets to increase the torque density. The result confirmed that increasing the width of permanent magnets was much more effective than increasing the thickness.