分数槽集中绕组永磁同步电机设计与分析

Analysis and Design of PMSM with Fractional-Slot Concentrated Windings

分数槽集中绕组永磁同步电机由于转矩密度高、弱磁性能好、齿槽转矩小和效率高等特点,广泛应用于航空航天、电动汽车等领域。本文研究了机载雷达伺服系统用分数槽集中绕组永磁同步电机,建立了电机的解析模型,分析了长径比、裂比、磁密系数等设计参数对电机性能的影响规律。结果表明,电机的输出转矩和质量分别与定子外径D3os,D2os成正比,绕组端部比重与长径比λ成反比,综合转矩密度和绕组端部比重两个因素,λ宜在0.2~0.4范围内选择。当定子裂比γ增加时,转矩密度先增大后减小,为使转矩密度最大,γ宜在0.6~0.8范围内选择。当磁密系数χ增加时,输出转矩先增大后减小,为使输出转矩最大,χ宜设计在1.75附近。基于理论分析和仿真计算,文中设计并加工了一台45槽38极分数槽集中绕组永磁同步电机,最后通过实验测试了其性能。

Permanent magnet synchronous machine（PMSM）with fraction-slot concentrated-winding（FSCW）is popularly applied in the field of aerospace and electric vehicle for its good flux-weakening capability,low cogging torque,and high torque density and efficiency.This paper mainly focuses on the PMSM-FSCW used for airborne radar servo system.With the magnetic circuit characteristics of PMSMFSCW,the analytic model of the motor is established.Influences of some design parameters,such as number of poles,ratio of length to diameter,split ratio and magnetic flux density coefficient on the motor performance are studied.Analytical results show that output torque and weight of the motor are respectively proportional to the outer diameters of stator,D3 osand D2 os,and the percentage of coil end to whole windings is inversely proportional to the ratio of stator length to its outer diameterλ.In view of torque density and percentage of coil end mentioned above,the value ofλis recommended from 0.2 to0.4.When split ratioγ,i.e.the ratio of stator inner diameter Disto outer diameter Dos,raises,output torque firstly increases and then decreases.Hence theγis advised to select in the range of 0.6—0.8 for the maximum torque density.When the ratio of the largest flux density in the stator iron core to air-gap flux densityχenlarges,output torque firstly increases and then decreases.χshould be designed at aboutthe value of 1.75 for the maximum output torque.Based on the theoretical analysis and simulation results above,aprototype of PMSM-FSCM,with the combination of 45-slot/38-pole,is designed and manufactured,and its performance is experimentally tested.