电动自行车用轮毂电机设计及其特性研究

硕士学位论文电动自行车用轮毂电机设计及其特性研究（应用型）DESIGNOFWHEELMOTORANDRESEARCHONITSCHARACTERISTICSFORELECTRICBICYCLE王殿明哈尔滨工业大学2011年6月国内图书分类号：TM351学校代码：10213国际图书分类号：621密级：公开工学硕士学位论文电动自行车用轮毂电机设计及其特性研究（应用型）硕士研究生：王殿明导师：郝明晖教授申请学位：工学硕士学科：机械设计及理论所在单位：机电工程学院答辩日期：2011年6月授予学位单位：哈尔滨工业大学ClassifiedIndex:TM351U.D.C:621DissertationfortheMasterDegreeinEngineeringDESIGNOFWHEELMOTORANDRESEARCHONITSCHARACTERISTICSFORELECTRICBICYCLE（ApplicationType）Candidate：WangDianmingSupervisor：Prof.HaoMinghuiAcademicDegreeAppliedfor：MasterofEngineeringSpeciality：MechanicalDesignandTheoryAffiliation：SchoolofMechatronicsEngineeringDateofDefence：June,2011Degree-Conferring-Institution：HarbinInstituteofTechnology哈尔滨工业大学工学硕士学位论文-I-摘要气候变暖、能源危机已成为21世纪人类所面临的共同挑战，而研究具有节能环保特点的电动自行车成为解决这些问题的重要途径。作为电动自行车核心的轮毂电机，其性能的好坏对整车功能的实现有决定性作用。而目前轮毂电机普遍存在着损耗大、性能不稳定、效率低等缺点，因此，研究一款控制精度高、结构可靠、稳定性好、运行效率高的轮毂式永磁同步电机具有重大意义。为了确定轮毂电机的总体方案，本课题首先分析了电动自行车对轮毂电机的性能要求，计算出轮毂电机的运动及动力学参数，确定电机的驱动力及输出扭矩。然后，通过分析电机常数，选择相关参数，计算出电机的主要尺寸，进而确定了轮毂电机总体机械方案。接着，引入单元电机的概念，对比不同绕组方案和极槽配合方案，确定轮毂电机的总体电磁方案。利用JMAG软件对轮毂电机的气隙磁场进行有限元分析，确定合理的气隙长度，优化气隙磁密波形。通过分析电枢磁密、输出扭矩及效率，对电机定子电枢的齿宽、轭高和永磁体的宽度及厚度等结构参数进行了优化。综合考虑永磁材料的性能及充磁成本，选择磁性能较高的钕铁硼永磁材料及平行充磁方式。然后，通过对轮毂电机空载反电动势进行有限元分析，得到了反电动势波形的叠加原理及对波形正弦性影响较大的谐波次数。接着，对电机的铁耗和铜耗进行了有限元计算，得出了轮毂电机优化设计后的效率。针对轮毂电机中存在的齿槽转矩，本课题进一步优化转矩特性，建立齿槽转矩的解析模型，通过分析解析模型得到削弱齿槽转矩的方法，并分析了不同电磁方案对齿槽转矩的影响。基于MATLAB/Simulink搭建轮毂电机的仿真平台，对电机的起动特性进行仿真分析，得到了速度、转矩、三相电流的响应特性。根据优化后的机械及电磁方案加工轮毂电机样机，对样机的反电动势、转矩、温升及效率进行系统的测试，试验结果表明样机的调速范围、响应特性、转矩输出及过载能力均满足设计要求，轮毂电机样机效率达到了88.9%,综合性能明显优于普通直流无刷轮毂电机，验证了课题中设计方案的合理性。关键词：电动自行车；轮毂式永磁同步电机；有限元法；齿槽转矩；仿真分析哈尔滨工业大学工学硕士学位论文-II-AbstractInthe21stcentury,climatewarmingandenergycrisishavebecomethecommonchallengesforhumans.Researchingtheelectricbicycle(EB)whichhastheadvantagesofenergysavingandenvironmentalprotectionbecomeanimportantwaytosolvetheseproblems.ThewheelmotoristhecoreofEB,anditsperformancesaredecisivefactorsforrealizingthefunctionofEB.Atpresent,wheelmotorhasthedisadvantagesofhighloss,performanceinstabilityandlowefficiency.Researchingawheeltypepermanentmagnetsynchronousmotor(WPMSM)whichhastheadvantagesofhighcontrolaccuracy,reliablestructure,goodstabilityandhighefficiencyhasimportantsignificance.Inordertodeterminetheoverallschemeofwheelmotor,firstly,analyzedtherequirementsofwheelmotorforelectricbicycle.Calculatedthekineticanddynamicparametersofwheelmotor;determinedthedrivingforceandoutputtorqueofwheelmotor.Then,byanalyzingmotorconstantandchoosingrelevantparameters,calculatedthemaindimensionsofwheelmotor,andthen,determinedgeneralmechanicalscheme.Further,introducedtheconceptofunitmotor;comparedthedifferentwindingandpoletoothslotscheme,anddeterminedgeneralelectromagneticschemeofwheelmotor.ByusingJMAGsoftware,finiteelementanalysisfortheair-gapmagneticfieldofwheelmotorwascarriedout,determinedreasonableairgaplength,andoptimizedtheair-gapfluxdensitywave.Throughanalyzingthearmaturemagneticdense,outputtorqueandefficiency,thetoothwidthandyokehighofmotorstatorarmaturewereoptimized,anddeterminedthewidthandthicknessofpermanentmagnetstructureparametersbythesamedesignoptimizationmethod.Consideringcomprehensivelythepermanentmagnetismmaterialsperformanceandcostofmagnetization,chosemagnetichigherNdFeBmaterialsandparallelmagnetizationway.Andthen,finiteelementanalysisfortheno-loadbackEMFofwheelmotorwascarriedout.ThesuperpositionprincipleofbackEMFwaveformandtheharmonicfrequencywhichhadgreatinfluenceonwaveformsineweregot.Further,calculatedtheironandcopperloss;gottheoptimaldesignefficiencyofwheelmotor.Aimedatthecoggingtorqueofthewheelmotor,furtheroptimizationoftorquecharacteristicswasmade.Establishtheanalyticalmodelofcoggingtorque.Throughanalyzingtheanalyticalmodel,gotthemethodtoweakencoggingtorque,andanalyzedtheinfluenceofdifferentelectromagneticschemetocoggingtorque.BasedontheMATLAB/Simulink,buildthesimulationplatformofwheelmotor.Usingthesimulationanalysistogetthestart-upcharacteristicsincludestheresponsecharacteristicsofpeed,torqueandthree-phasecurrents.哈尔滨工业大学工学硕士学位论文-III-Accordingtotheoptimizedmechanicalandelectromagneticscheme,wheelmotorprototypewasprocessed.ThebackEMF,torque,temperatureriseandefficiencyoftheprototypeweresystematicallytested.Testresultsshowedthatthespeedrange,responsecharacteristic,torqueoutputandoverloadabilityofprototypeallmetthedesignrequirements.Theefficiencyofprototypereached88.9%,itscomprehensiveperformancewasbetterthanordinarybrushlessdcmotor,andverifiedtherationalityofthedesignschemesinthesubject.Keywords:Electricbicycle,WheeltypePMSM,Finiteelementmethod,Coggingtorque，Simulationanalysis哈尔滨工业大学工学硕士学位论文-IV-目录摘要..........................................................................................................................IABSTRACT...............................................................................................................II目录.......................................................................................................................IV第1章绪论...............................................................................................................