In order to describes an investigation of interior permanent magnet (IPM) synchronous machines with higher winding factor, this paper presents a detailed comparisons of the 18-slot/10-pole IPM machine equipped with two coil pitches with conventional one coil pitch fractional slot 18-slot/10-pole machine for applications that require optimal flux weakening operation, which are including the predicted air gap flux density, back-EMF, average torque, torque ripple and d-axis and q-axis designed by finite element analysis (FEA). With this result, a better structure is carried out to determine the coil pitch, compared with the one coil pitch machine, the two coil pitches increase the winding factor and have better performance in the machine without significant increases in the ripple torque.

IPM synchronous machine， Fractional slot winding， Coil pitches， Winding Factor， FEA