Induction motor performance as a function of phase number

An analytical and experimental comparison of the performance of multiphase induction machines as a function of the number of phases is provided. The method of generalised complex harmonic analysis is used to model the multiphase machine, including the calculation of pulsating torques. This general model is validated with experimental results. The test machine used a standard motor frame, which had been modified to bring every coil out to a patch panel. With 12 coils per pole, the machine was tested in 3, 4, 6 and 12-phase operation. Results show moderate reductions in stator losses and significant improvements in pulsating torques