90永磁直流电机电磁设计算例

手工输入公式计算，不可改．关键判定，提示说明．数据引用序号名称符号或算式单位一额定数据1额定功率PNW2额定电压UNV额定转速nNrpm额定电流INA额定转矩TN=9.549*PN/nNN.m起动转矩倍数TstN二主要尺寸及永磁体尺寸选择额定效率ηN=PN/(UN*IN*COSØ)*100%计算功率P'=((1+2η/100)/(3ηN/100))*PNW感应电势E'a=((1+(2ηN/100))/3)*UNV极对数p永磁材料类型预计永磁体工作温度t℃永磁体剩磁密度Bt20T工作时永磁体剩磁密度Br=(1-(t-20)*αBr/100)*(1-IL/100)*Bt20T剩磁温度系数αBr%K-1剩磁温度不可逆损失率IL%永磁体计算矫顽力Hc20KA/M工作时永磁体计算矫顽力Hc=(1-(t-20)*αBr/100)*(1-IL/100)*Hc20KA/M永磁体相对回复磁导率μr=Br/(μ0*Hc)/1000真空磁导率μ0=4*PI*10-7工作温度下退磁曲线的拐点bk电枢铁心材料铁芯叠加系数KFe电负荷预估值A'A/cm气隙磁密预估值B'δ=(0.60-0.85)Br=0.8BrT永磁直流电机电磁计算程序和算例:计算极弧系数αi=0.6-0.75长径比预估值λ=0.6-1.5电枢直径Da=(6.1*P'*104/α'*A'*B'δ*nN*λ)1/3cm电枢直径圆整cm电枢长度La=λDacm电枢长度圆整cm极距τ=PI*Da/(2p)cm气隙长度δcm永磁体结构型式极弧系数αP,αP=αI磁瓦圆心角θP,θP=αP*180(°)永磁体厚度hM永磁体轴向长度LM,LM=LacmLM,LM=(1.1-1.2)Lacm电枢计算长度Lef,Lef=La+2δcmLef,Lef=La+△L'a(hM+δ)cm△L'a=(0.45-0.5)((LM-La)/(hM+δ))永磁体内径Dmi=Da+2δcm永磁体外径Dmo=Dmi+2hMcm电枢圆周速度Va=pi*Da*nN/6000m/s机座材料-机座长度Lj=(2.0-3.0)La,取Lj=2.8Lamm机座厚度hj=σ*αi*τ*Lef*B'δ/(2*Lj*B'j)cm机座厚度圆整cm计算机座轭磁密B'j,B'j=(1.5-1.8)TT漏磁系数σ,σ=(1.1~1.3)机座外径Dj=Dmo+2hj三电枢冲片及电枢绕组计算绕组型式绕组并联支路对数a,a=p槽数Q槽距t2=pi*Da/Qcm预计满载气隙磁通Ф'δ=α'*τ*Lef*B'δ*10-4Wb预计导体总数N'=60*a*E'a/(p*Ф'δ*nN)每槽导体数N'S=N'/Q每槽元件数u每元件匝数W'S=N'S/(2*u)每元件匝数圆整为Ws实际每槽导体数Ns=2*u*Ws实际导体总数N=Q*Ns换向片数K=u*Q实际电负荷A=N*IN/(2*pi*a*Da)支路电流Ia=IN/(2*a)预计电枢电流密度j'2=5-13A/mm²预计导线截面积A'Cua=Ia/j'2并绕根数Nt计算导线裸线线径d'0=(4A'Cua/PI)1/2导线裸线线径d0mm导线绝缘后线径dmm实际导线截面积ACUa=PI*Nt*d02/4mm²实际电枢电流密度j2=Ia/ACUa实际热负荷△=AJ2槽形选择槽口宽度b02cm槽口高度h02cm槽下度半径r22cm槽上部倒角半径r23cm槽上部高度h2,h2=r23cm槽上部宽度d1cm槽中部高度h22cm槽下部宽度d2cm槽下部倒角圆心距d3cm槽高ht2cm齿宽bt2,近似取平行齿cm槽净面积As=PI*(r222+r232)/2+h22(d1+2r22)+r23*d3-Ci(PI*r22+2*h22+d1)cm²槽绝缘厚度Cicm槽满率Sf=Nt*Ns*d2/As%线圆平均半匝长度Lav=La+Ke*Da,Ke=(1.35,p=1)cm电枢绕组电阻Ra=ρ*N*Lav/(4*Acua*a2)Ra20(ρa20=0.1785*10-3Ω.mm2/cm)ΩRa75(ρa75=0.217*10-3Ω.mm3/cm)Ω转子冲片内径Di2,Di2=(0.15-0.25)Damm转子冲片内径圆整mm电枢轭高hJ2=(Da-2*ht2-Di2)/2mm电枢轭有效高hj21=hj2+Di2/8mm四磁路计算气隙系数Kδ,Kδ=(1.01-1.1)气隙磁通密度Bδ=Ф'δ*104/(α*τ*Lef)T每对极气隙磁位差Fδ=1.6*Kδ*δ*Bδ*104A电枢齿磁通密度Bt2=t2*Lef*Bδ/(bt2*La*Kfe)T电枢齿磁场强度Ht2(查磁化曲线图表)A/cm电枢齿磁位差Ft2=2*ht2*Ht2A电枢轭磁通密度Bj2=Ф'δ*104/(hj21*La*Kfe)T电枢轭磁场强度Hj2(查磁化曲线图表)A/cm电枢轭磁位差Fj2=Lj2*Hj2A电枢轭部磁路平均计算长度Lj2=PI*(Dj2+hj2)/2pcm定子轭磁通密度Bj=σ*Ф'δ*104/(2*hj*Lj)T定子轭磁场强度Hj1,Hj1(查磁化曲线图表)A/cm定子轭磁位差Fj1=Lj1*Hj1A定子轭部磁路平均计算长度Lj1=PI*(Dj-hj)/2pcm外磁路总磁位差∑F=Fδ+Ft2+Fj2+Fj1五负载工作点计算气隙主磁导Λδ=Ф'δ/ΣF磁导基值-主磁导标么值-外磁路总磁导-直轴电枢去磁磁动势-永磁体负载工作点-实际气隙磁通Фδ六换向计算电刷尺寸,电刷长Lbcm电刷尺寸,电刷宽bbcm电刷尺寸,电刷对数pb电刷面积Ab=Lb*bbcm²每杆电刷数Nb电刷电流密度Jb=IN/(Nb*pb*Lb*bb)A/cm2换向器长度Lkcm一对电刷接触压降△UbV换向器直径DK,DK=(0.5-0.9)Dacm换向器圆周速度Vk=PI*DK*nN/6000m/s换向器片距Tk=PI*DK/K换向元件电抗电动势-换向元件交轴电枢反应电动势-换向元件中合成电动势-换向区宽度-换向区宽度检查-七最大去磁校核不同工况时的最大瞬时电流突然起动时Imax=(UN-△Ub)/Ra20瞬间堵转时Imax=(UN-△Ub)/Ra75突然停转时Imax=(Ea-△Ub)/Ra75突然反转时Imax=(UN+Ea-△Ub)/Ra75直轴电枢磁动势-交轴电枢磁动势-换向元件电枢磁动势-电枢总去磁磁动势-电大去磁时永磁体工作点-可逆退磁校核八工作特性电枢绕组铜耗Pcua=IN2*Ra75电刷接触电阻损耗pb=IN*△Ub电枢铁损耗PFe=k*p10/50(f/50)1.3*(mt2*Bt22+mj2*Bj22)k=2-3铁损系数p10/50,查铁损手则W/kgf=p*nN/60Hz电枢齿质量mt2=7.84*Kfe*La*(PI/4*(Da2-(Da-2*ht2)2)-Q*As)*10-3kg电枢轭质量mj2=7.84*Kfe*La*PI/4*((Da-2*ht2)2-Dt22)*10-3kg电刷对换向器的磨擦损耗pKbm=2*μ*pb*Ab*pS*VkW电刷单位面积压力Ps=2-6N/cm2(或=200-600g/cm2)N/cm²电刷摩擦系数μ,μ=0.2-0.3轴承磨擦和电枢对空气磨擦损耗pBf+pWf≈0.04PNW总机械损耗ptW=pKbm+pBf+pWfW总损耗∑P=Pcua+Pb+Pfe+PtWW输入功率P1=PN+∑PW效率η=PN/P1*100%电流校核I'N=P1/UNA实际感应电动势Ea=UN-△Ub-I'N*Ra75V满载实际转速n=60*α*Ea/p*Фδ*Nrpm起动电流Ist=(UN-△Ub)/Ra20A起动电流倍数Ist/I'N起动转矩Tst=p*N*Фδ*Ist/(2*PI*a)N.m起动转矩倍数Tst/TN算例75.00230.003,900.000.580.1628321224.566.1433988987.79666667178.0865451铁氧体400.3950.37920.20290278.41.0839000431.25664E-060.15DR510-500.97700.30336永磁直流电机电磁计算程序和算例:0.70.630.6297709925.2645431225.24OK3.30123.3OK8.2309727520.08瓦片形0.72129.60.853.3钕铁硼3.96铁氧体3.46钕铁硼3.6168铁氧体0.3406451615.47.110.700264589.242.8030303030.2593408110.25OK1.61.2137.6单叠1161.0288715940.0006321674333.968375270.87302341135.4365117135135422.573964527043201676.102791110.2970.04142857110.2296704060.23OK0.25漆膜厚度0.01mm0.0415475636.979952136531.1938393半梨形槽0.270.1150.20.10.10.6950.6944412910.7230.7230.40.4951.1380.2494412910.460187990.02336.6697966110.3741148.1351873258.517286540.7860.8OK1.0821.1821.0890.269372444375.48363781.25540778665147.940.8354084572162.081012432.9562386871.65978119236415.632708111.5453531001.1373586.31449E-070.000630.0006321670.60.5310.31811.8238993711.42.53.26.5345127190.6283185314.7262722493.8877400763.000592737289.82188319.685215191.457.57632861436.3500.1832544770.160545633.324760072×pb是错误的3.20.2536.32476007235.03630388110.0468.15932320.478418713NO199.50423514398.2415154.7262722499.8789452112.04721362212.57254155