A new dual-ferrite–assisted hybrid reluctance machine with two-stage excitation for starter generator application

Reluctance machines with DC field coil in stator are a competitive candidate for starter generation application, due to the elimination of rare-earth permanent magnet (PM), robust structures, and controllable excitation. However, poor excitation ability coils, torque density is disadvantageous. Moreover, increase current, it exposed risk extra saturation teeth. As consequence, efficiency both constrained. To solve aforementioned problems, based on comprehensive consideration production cost performance, this study proposed novel type hybrid reluctance machine dual-ferrite–assisted slots. The inner-layer ferrite PM magnetized tangentially, which can effectively achieve DC-saturation–relieving effect, while outer-layer radially through flux modulation effect. Based finite element analysis, be improved by 20 5%, respectively. Furthermore, simplify system terminal, two-stage method splitting some turns armature winding feed passive rectifier. No power switching devices needed way, making highly robust. effectiveness design verified time-stepping analysis.