问题
多项选择题
绕线式三相异步电动机可以采用( )进行调速。
A.改变电源频率f
B.改变额定电压UN
C.改变额定电流IN
D.改变转子磁极对数P
E.改变转差率S
答案
参考答案:A,D,E
绕线式三相异步电动机可以采用( )进行调速。
A.改变电源频率f
B.改变额定电压UN
C.改变额定电流IN
D.改变转子磁极对数P
E.改变转差率S
参考答案:A,D,E
根据句意从方框中选用合适的词组,并用其适当形式填空。
2. I hope to visit the Great Wall _____. 3. Why do some students want to start work _____? 4. I like games _____, and especially football. 5. _____, you had better do it one by one. |