Research On A Less Rare Earth Interior Curved Permanent Magnet Synchronous Machine Used For Elecrric Vehicle

Electric vehicle (EV) is developed with Effective motor control system andelectromechanical coupling system, based on Traditional vehicle tractionstructure.With advantages as high efficiency and stable operation, it’s consideredthe most Applicable new energy vehicle technology to the current energy situationand our Industrial process. The driving dynamics in EV is provided by the drivemotor, in Hybrid cars is also provided by a electromechanical coupling systemworked with internal-combustion engine. so the efficiency and reliability are therequirement in designing drive motors. Compared with other kinds of drive motors,permanent magnet synchronous motors (PMSM) is more Effective. but the designand optimization process still needs many times. Especially, faced on the shortageof rare earth resources, it has more Realistic significance to improve the efficiencyof utilization of high-performance permanent magnet material.The writer uses the method combining magnetic circuit calculation and finiteelement simulation to design the sample motor, according to the performancerequirement of motor car from source of the topic. Then the paper researches theinfluence of the Structure parameters of rotor curved barriers. The influencecontains The distribution of electromagnetic field, EMF characteristic, and torquecharacteristics. After that the inductance parameters and the ability of resistance todemagnetization has been analyzed.Firstly, the writer researches the influence of the Structure parameters of rotorcurved barriers and the Permanent magnet fit in them. That are reflected in the thesaliency ratio and The distribution of electromagnetic field. The barriers andPermanent magnet affects Some aspects both and each. So the paper needs overallconsiderate The distribution of electromagnetic field, EMF, torque characteristics，and utilization rate of permanent magnet material.Secondly, the writer researches the inductance parameters of the motor. Twokinds of Method of calculation of inductance, which considered Cross couplingphenomenon, have been elaborated and compared.“Method of Load” is moresuitable to calculation. Combined finite element analysis the paper calculates andanalyzes all inductance parameters.At last, in the research of the ability of resistance to demagnetization, thewriter begin from physical meaning. Then combined finite element analysis, thewriter analyzes several kinds of the limit demagnetization case when the motoroperates stably. The limit demagnetization case consists of: loading maxdemagnetization current, and stator winding short-circuit working. The writer’s research provides a theoretical reference and analytical methods,for the optimization of the machine rotor Structure and inductance parameterscalculation, lays a theoretical and experimental basis for the next step optimaldesign functional sample motor.