【简答题】suppose your class is to hold a charity sale for kids in need of help. write your classmates an email to 1) inform. them about the details and 2)encourage them to participate 100 words use LiMing.Don&...
【简答题】一台笼型三相异步电动机,定子绕组Y形联结,其技术数据为:额定功率P N =40kW,额定线电压U 1N =380V,额定电流I N =87.2A,起动电流倍数K T =6.3,起动转矩倍数K st =1.2。要求该电动机起动时最大电流不超过350A,现有一台三相对称电抗器,每相电抗为X=0.3Ω。如果用该电动机拖动通风机工作,试问能否采用定子串接该电抗器减压起动?