毕业论文：单绕组多速电动机的研究.doc

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均与国际同类产品的先进水平相近。变极多速三相异步电动机由于具有可随负载性质的要求而分级地变化转速，从而达到功率的合理匹配和间化变速系统的特点。电动机用于各式万能、组合、专用切削机床以及矿山冶金、纺织、印染、化工、农机等部门需要调速的各种传动机构。编著者2004-6-11ormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraaaaaaaaaaaaaaaaaaaaaaaaaaaaaphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormSelection.ParagraphFormaaaaaaaaaaaaaaaaaaaaaaaaaaaaat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormat.LineSpacingLinesToPoints(2Selection.ParagraphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraphFormat.LineSpacingLinesToPoints(2)Selction.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormat.LineSpacingLinesToPoints(2)Selction.ParagraphFaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaahFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraaaaaaaaaaaaaaaaaaaaaaaaaaaaaphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormSelection.ParagraphFormaaaaaaaaaaaaaaaaaaaaaaaaaaaaat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormat.LineSpacingLinesToPoints(2Selection.ParagraphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraphFormat.LineSpacingLinesToPoints(2)Selction.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormat.LineSpacingLinesToPoints(2)Selction.ParagraphFaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaahF第4页共74页目录摘要1前言2一、技术要求4二、单绕组多速电动机的概况5三、定子绕组方案的确定及分析6四、多速电动机的变极调速原理及设计特点9（一）单绕组变极调速的基本原理9（二）单绕组多速异步电动机的设计特点13五、多速电动机的变极调速方法、功率和定子绕组结法及气隙磁密的相互关系16（一）单绕组变极电动机的转动方向问题17（二）不同的改接方法时，电动机功率及转矩的变化17（三）不同的改接方法时，电动机气隙的磁通密度的变化20六、电磁计算程序框图21ormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraaaaaaaaaaaaaaaaaaaaaaaaaaaaaphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormSelection.ParagraphFormaaaaaaaaaaaaaaaaaaaaaaaaaaaaat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormat.LineSpacingLinesToPoints(2Selection.ParagraphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraphFormat.LineSpacingLinesToPoints(2)Selction.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormat.LineSpacingLinesToPoints(2)Selction.ParagraphFaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaahFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraaaaaaaaaaaaaaaaaaaaaaaaaaaaaphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormSelection.ParagraphFormaaaaaaaaaaaaaaaaaaaaaaaaaaaaat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormat.LineSpacingLinesToPoints(2Selection.ParagraphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraphFormat.LineSpacingLinesToPoints(2)Selction.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormat.LineSpacingLinesToPoints(2)Selction.ParagraphFaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaahF第5页共74页七、多速电动机电磁设计程序分析及电磁设计22（一）四极电磁设计程序分析及电磁设计22（二）二极电磁设计程序分析及电磁设计39八、结构设计57九、致谢58十、参考文献59附录一601、绕组展开图602、电机装配图613、电机转子图62附录二起动全过程特性曲线63一、技术要求1、课题名称：单绕组多速电动机的研究2、设计要求：单绕组多速电动机的概况；定子绕组方案的确定及ormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraaaaaaaaaaaaaaaaaaaaaaaaaaaaaphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormSelection.ParagraphFormaaaaaaaaaaaaaaaaaaaaaaaaaaaaat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormat.LineSpacingLinesToPoints(2Selection.ParagraphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraphFormat.LineSpacingLinesToPoints(2)Selction.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormat.LineSpacingLinesToPoints(2)Selction.ParagraphFaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaahFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraaaaaaaaaaaaaaaaaaaaaaaaaaaaaphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormSelection.ParagraphFormaaaaaaaaaaaaaaaaaaaaaaaaaaaaat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormat.LineSpacingLinesToPoints(2Selection.ParagraphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraphFormat.LineSpacingLinesToPoints(2)Selction.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormat.LineSpacingLinesToPoints(2)Selction.ParagraphFaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaahF第6页共74页分析；多速电动机的变极调速及设计特点；多速电动机电磁设计程序分析及电磁设计；了解和掌握三相单绕组多速电动机的变极调速方法、功率和定子绕组结法及气隙磁密的相互关系。3、技术指标1）型号：YD132M-4/22）功率：6.5/83）额定电压：380伏4）接法：2Y5）绝缘等级：B级6）效率：84807）功率因数：0.850.898）过载能力：1.81.89）转动转矩倍数：1.71.810）起动电流倍数：6.5711）槽配合：3632二、单绕组多速电动机的概况ormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraaaaaaaaaaaaaaaaaaaaaaaaaaaaaphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormSelection.ParagraphFormaaaaaaaaaaaaaaaaaaaaaaaaaaaaat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormat.LineSpacingLinesToPoints(2Selection.ParagraphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraphFormat.LineSpacingLinesToPoints(2)Selction.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormat.LineSpacingLinesToPoints(2)Selction.ParagraphFaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaahFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraaaaaaaaaaaaaaaaaaaaaaaaaaaaaphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormSelection.ParagraphFormaaaaaaaaaaaaaaaaaaaaaaaaaaaaat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormat.LineSpacingLinesToPoints(2Selection.ParagraphFormat.LineSpacingLinesToPoints(2)Selection.ParagraphFormat.LineSpacingLinesToPointselection.ParagraphFormat.LineSpacingLinesToPoints(2)Selction.ParagraphFormat.LineSpacingLinesToPoction.ParagraphFormat.LineSpacingLinesToPoints(2)Selction.ParagraphFaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaahF第7页共74页单绕组多速异步电动机是利用改变定子绕组的接法，以改变电机的极数，从而使电机用一套绕组获得两种或两种以上转速的多速异步电动机。由于一般异步电动机正常运行时的转差率s都很小，电机的转速n=n1(1-s)决定于同步转速n1。从pfn1160可见，在电源频率1f不变的情况下，改变定子绕组的极对数p，同步转速n1就发生变化，例如极对数增加一倍，同步转速就下降一半，随之电动机的转速，也约下降一半。显然，这种调速方法只能做到一级一级地改变转速，而不是平滑调速。变极电动机一般都用鼠笼式转子，因为鼠笼转子的极对数能自动地随着定于极对数的改变而改变，使定、转子磁场的极对数总是相等而产生平均电磁转矩。若为绕线式转于，则定子极对数改变时，转子绕组必须相应地改变接法以得到与定于相同的极对数，很不方便。要使定子具有两种极对数，容易想到的办法是用两套极对数不同的定子绕组，每次用其中一套，即所谓双绕组变极，显然，这是一个很不经济的办法，只在特殊情况下才采用。理想的办法是：只装一套定子绕组而用改变绕组接法来获得两种或多种极对数，即所谓单绕组变极。其中倍极比情况(如24极，48极等)，和非倍极比(如46极，68极等)以及三速(如468极等)。