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UN?INRa440?76*0.376??0.411nN1000cT??9.55ce??3.93IR76*0.376?n?Na??69.53ce?0.411U440n0?N??1070r/mince?0.411(1)降压调速的最低理想空载转速为250r/min,相应的额定转矩最低转速为：250?69.53?180.47r/min(2)弱磁时的最高理想空载转速为：U440ce?'?N??0.2933n0'15000.2933?'???0.714?0.411对于恒转矩负载而言，弱磁后的电流为：U?1440I'?IN?*76?106.4,n0'?N??1500?'0.714ce?'0.2933额定转矩时的转速为：U?I'Ra440?106.4*0.376nN'?N??1363.8r/mince?’0.2933(3)最高转速机械特性的斜率与静差率：Ra0.376?’???0.457722cecT?’9.55*0.2933n'?n'1500?1363.8?‘?0N??0.09n0'1500(4)最低转速机械特性的斜率与静差率：4-10
Ra0.376?’’???0.23322cecT?9.55*0.41169.53?‘??0.278250ce???
UN?INRa220?280*0.044??0.327nN635cT??9.55ce??3.12(1)电枢串电阻：U?ce?n220?0.327*500R?N?Ra??0.044?0.158?IN280（2）降压调速U?ce?n?INRa?0.327*500?280*0.044?175.8V4-11 (3)?1I'?IN?*IN?IN,不能长期运行?'0.85U?I'Ra220?280/0.85*0.044n?N??739.4r/mimce?'0.327*0.85ce??。
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UN?INRa220?158.5*0.1??0.204nN1000cT??9.55ce??1.95带上0.8倍额定负载时UN?0.8INRa220?0.8*158.5*0.1(1）n???1016.3r/mince?0.204（2）电枢回路串入0.3?电阻时，电枢电流维持0.8倍额定电流不变：U?0.8IN（Ra?R)220?0.8*158.5*(0.1?0.3)n?N??830r/mince?0.204V时，电枢电流同样维持0.8倍额定电流不变4-12 (3)电枢电压为180U?0.8INRa180?0.8*158.5*0.1n???820r/mimce?0.2041（4）磁通减弱到0.8倍额定磁通时，负载转矩不变，Ia?*0.8IN?IN0.8U?INRa220?*158.5*0.1n?N??1251r/mimce?'0.204*0.8ce??
UN?INRa220?68.7*0.224??0.136nN1500cT??9.55ce??1.3U220n0?N??1617.6r/mince?0.136带上额定负载时n?nmin(1）??0?0.3n0nmin?n0(1??)?0.7*1617.6?1132.4r/minn1500(2)电动机调速范围为D?max??1.325nmin1132.4(3)电枢回路串入电阻值：ce??4-13
UN?IN（Ra?R)220?68.7*(0.224?R)??1132.4r/mince?0.136R?0.737?(4)拖动额定负载转矩时电动机输入功率P1?UNIN?220*68.7?15114Wn1132.4输出功率P2?minPN?*13000?9814WnN15002外串电阻上的损耗pcu?INR?3478.4W显然效率较低nmin?
。
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UN?INRa220?22.3*0.91??0.2nN1000cT??9.55ce??1.91U220n0?N??1100r/mince?0.136带上额定负载时(1）电压反接制动，制动开始时的制动电流为：?UN?ce?nN?220?0.2*1000Ia????42.38ARa?R0.91?9因此制动