问题 问答题 简答题

简述励磁调节器的起励过程?

答案

参考答案:

励磁调带器控制回路能够正常工作所需的整流桥输入电压一般为5V。如果整流桥输入电压大于或等于该值,首先使用残压起励,连续触发晶闸管整流桥,电压升至额定值。如果整流桥输入电压小于5V起励回路会自动闭合,为整流桥提供输入电压,当机端电压达到发电机额定电压的10%时,整流桥已能正常工作,起励开关自动退出,软起励过程开始并将发电机电压升到额定值。整个起励过程的控制和监测都是由AVR软件实现的。

填空题

阅读短文,根据首字母提示填入适当的词。

     Young people are often unhappy when they are with their parents. They say that their parents don't

1. u_______ them. They often think their parents are too strict 2. w_______ them. Parents often find it

difficult to win their 3. c_______ trust, and they seem to forget how they themselves felt when they

were young. 

     For example, young people like to do things without much 4. t_______. It's one of their ways to show

that they grow up and they can solve any difficult 5. p_______. But older people always think 6. m than

young people. Most of them plan things ahead and don't like their plans to be 7. c_______, so when you

want your parents to let you do something, you will succeed easily if you ask before you really start doing it. 

     Young people often make their parents angry by the 8. c_______ they wear, the music they enjoy and

something else. But they don't mean to cause any trouble. They just want to be cut off (摆脱) from the old

people's world and they are 9. t_______ to make a new culture of their own. And if their parents don't like

their music or clothes or their ways of speech, the young people feel very sad. Sometimes instead of going

out with their parents, they just want to stay at home 10. a_______ and do what they like.

      If you plan to do something, you'd 11. b_______ win your parents over and get them to understand you,

if so, your parents will certainly let you do 12. w_______ you want to do.

1.______ 2.______ 3.______ 4.______ 5._______ 6.______

7.______ 8.______ 9.______ 10.______ 11.______ 12.______

单项选择题