Effect of toothless stator design on the dynamic performance characteristics of high speed permanent magnet generator-load systems

The results of a study on the effect of toothless stator design on the dynamic performance characteristics of high speed permanent magnet generator-load systems are presented. This study is based on the use of magnetic field solutions and state space models which account for saturation due to magnetic material nonlinearities and space harmonics due to machine geometry. Two particular stator designs, a toothless stator and a conventional type stator (with iron teeth), are considered in this study when feeding AC and DC rectified loads. Based on this study, it is demonstrated that the toothless design for this class of PM generators could result in lower levels of harmonics in the various machine voltages and currents waveforms as well as the power delivered to the loads. In addition, some design modifications are discussed to boost the output power level of the toothless machine which are inherently lower than the conventional machine due to the larger effective airgap that exists in the toothless design