Contents I. Introduction
In recent years the development in magnetic materials, power electronics devices, and control principles made permanent magnet synchronous motor (PMSM) to play a significant role in precise motion control applications. In last decade use of the PMSM drives in high performance motion control applications (household applications like; washing machine, blower, grinder, and industrial applications like; robots, compressors, rolling mills). The advantages of PMSM over dc motor are; less audible noise, longer life, sparkless operation, higher speed, better heat transfer, higher power density and smaller size. Advantages of PMSM over induction motors are; higher efficiency, higher power factor, higher power density and smaller size, and better heat transfer. Moreover popularity of PMSM comes from their desirable features; compact size, high efficiency, low noise and robustness, high torque to inertia ratio, high torque to current ratio, high air gap flux density, and high acceleration and deceleration rate.
