有源逆变在生产中的应用有()。 A.异步电机转子串电阻调速 B.异步电机定子调压调速

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问题:

有源逆变在生产中的应用有()。

A.异步电机转子串电阻调速

B.异步电机定子调压调速

C.直流可逆调速系统

D.绕线式异步电动机串级调速

E.高压直流输电

考点:电工电工综合练习电工综合练习题库
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Lying in the sun on a rock, the cougar saw Jeb and his son, Tom, before they saw it. Jeb put his bag down quickly and pulled his jacket open with both hands, making himself look big to the cougar. It worked. The cougar hesitated, ready to attack Jeb, but ready to forget the whole thing, too.
Jeb took off his jacket, grasped Tom and held him across his body, making a cross. Now the cougar’s enemy looked even bigger, and it rose up, ready to move away, but unfortunately Tom got scared and struggled free of Jeb.
"Tom, No !" shouted his father.
But Tom broke and ran and that’s the last thing you do with a cougar. The second Tom broke free, Jeb threw himself on the cougar, just as it jumped from the rock. They hit each other in mid air and both fell. The cougar was on Jeb in a flash, forgetting about Tom, which was what Jeb wanted. Cougars are not as big as most people think and a determined man stands a chance, even just with his fists. As the cougar’s claws got into his left shoulder, Jeb swung his fist at its eyes and hit hard. The animal howled(吼叫) and put its head back. Jeb followed up with his other fist. Then out of the corner of his eye, Jeb saw Tom. The boy was running back to help his father.
"Knife, Tom," shouted Jeb.
The boy ran to his father’s bag, while Jeb started shouting as well as hitting, to keep the cougar’s attention away from Tom. Tom got the knife and ran over to Jeb. The cougar was moving its head in and out, trying to find a way through the wall. Jeb was making out of his arms. Tom swung with the knife, into the cougar’s back. It howled horribly and ran off into the mountains.

How did Jeb try to hold the cougar’s attention

A.By keeping shouting and hitting.
B.By making a wall out of his arms.
C.By throwing himself on the cougar.
D.By swinging his fists at the cougar’s eyes.

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展览会结束后,入境展览物品的处置方式有()。

A.销毁

B.退运

C.发放

D.留购

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深圳婚假包括双休日吗?

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没有约定保证份额的,保证人承担连带责任,债权人可以要求任何一个保证人承担全部保证责任,保证人都负有担保全部债权实现的义务。()

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在科学管理理论中,提出五大管理职能和14条管理原则的是()。

A.法约尔

B.韦伯

C.泰勒

D.勒温

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