An investigation of slot-pole combinations for interior permanent magnet synchronous machines with different magnet topologies

In this paper three different magnet configurations, e.g. single V-shape, double V-shape and delta-shape are investigated in the integer-slot 48/8 and fractional slot 36/8 interior permanent magnet synchronous machines (IPMSM). An optimization procedure for maximizing torque per ampere is used to compare these six motor models under the same output torque levels. The torque qualities at both low- and high-speed points for these six motor models are studied first. Fast Fourier Transform (FFT) analysis is also performed on the torque waveforms. Harmonics of magnetomotive force of the rotors and stators are analyzed. Radial force waveforms are also compared for these motor models. 36/8 winding configuration improves torque quality at both low- and high-speed points.