With the increasing demand for high torque density in motors,more and more new topologies emerge.Furthermore,the magnetic field modulation principle is widely concerned and has evolved into an effective analysis metho...With the increasing demand for high torque density in motors,more and more new topologies emerge.Furthermore,the magnetic field modulation principle is widely concerned and has evolved into an effective analysis method for studying the new motor topology.This paper introduces the principle of magnetic field modulation.And the research on high torque density in recent years is reviewed from the perspective of magnetic field modulation,including permanent magnet vernier machine(PMVM),flux reverse machine(FRM),flux switching machine(FSM),dual permanent magnet(DPM)machine,and DC biased machine.The principle of magnetic field modulation makes it possible to propose higher torque density topologies in the future.展开更多
The split ratio which is defined as the ratio between rotor and stator outer diameters is critical for permanent magnet(PM)machines.In this paper,the split ratio in small high speed PM machines is optimized analytical...The split ratio which is defined as the ratio between rotor and stator outer diameters is critical for permanent magnet(PM)machines.In this paper,the split ratio in small high speed PM machines is optimized analytically by considering both stator and rotor loss limitations.By this way,the thermal constrains in both stator and rotor parts can be taken into account.It shows that both losses can significantly affect the optimal split ratio and the machine performance.By considering the influence of rotor losses,especially the rotor eddy current loss,the optimal split ratio is increased significantly in certain scenarios.The output torque is calculated analytically and the influences of several key design parameters on the optimal split ratio,i.e.slot/pole combinations and magnet materials,are also investigated in details.Finally,finite element(FE)analyses are carried out for validating of the analytical model.展开更多
基金supported in part by the National Natural Science Foundation of China(NSFC)under Project No.51737010the National Key R&D Program of China under Grant 2020YFA0710500。
文摘With the increasing demand for high torque density in motors,more and more new topologies emerge.Furthermore,the magnetic field modulation principle is widely concerned and has evolved into an effective analysis method for studying the new motor topology.This paper introduces the principle of magnetic field modulation.And the research on high torque density in recent years is reviewed from the perspective of magnetic field modulation,including permanent magnet vernier machine(PMVM),flux reverse machine(FRM),flux switching machine(FSM),dual permanent magnet(DPM)machine,and DC biased machine.The principle of magnetic field modulation makes it possible to propose higher torque density topologies in the future.
文摘The split ratio which is defined as the ratio between rotor and stator outer diameters is critical for permanent magnet(PM)machines.In this paper,the split ratio in small high speed PM machines is optimized analytically by considering both stator and rotor loss limitations.By this way,the thermal constrains in both stator and rotor parts can be taken into account.It shows that both losses can significantly affect the optimal split ratio and the machine performance.By considering the influence of rotor losses,especially the rotor eddy current loss,the optimal split ratio is increased significantly in certain scenarios.The output torque is calculated analytically and the influences of several key design parameters on the optimal split ratio,i.e.slot/pole combinations and magnet materials,are also investigated in details.Finally,finite element(FE)analyses are carried out for validating of the analytical model.
