问题 问答题 论述题

在现场整定调节器参数时应注意哪些问题?

答案

参考答案:

整定调节器参数是一项十分细致的工作,既要知道调节器参数对生产过程的影响,又要经常观察生产过程运行情况,做到不影响生产,又要把调节器参数整定好。一般应注意以下几个问题:(1)用各种方法得到的整定参数值都是一个范围,一定要根据生产实际情况进行现场修改。(2)整定调节器参数最好在生产过程工况比较稳定时进行,除了适当地人为给予扰动外,最好通过较长期地观察生产过程自然的扰动来修改调节器参数(最好接一只快速记录表)。(3)人为施加扰动,一般有内扰、外扰和给定值扰动三种。给定值扰动对生产过程影响较大,一定要控制好其扰动量,内扰和外扰时也要注意扰动量大小。施加一次扰动后,一定要等待一段时间,观察被调参数的变化情况,在未弄清情况时,不要急于加第二次扰动。(4)对于PID调节器,要考虑参数间的相互干扰。按整定方法得到的调节器参数值不是调节器参数的实际刻度值,要用调节器相互干扰系数加以修正后才是实际刻度值。(5)整定参数时,要考虑调节对象和调节机构的非线性因素。若非线性严重,整定参数要设置得保守一些。(6)整定时,要考虑生产过程的运行工况。一般讲,调节器参数的适应范围是经常运行的工况。若运行工况变化很大时,调节器参数就不适应了。这不是调节器参数未整定好,而是参数适应范围有限,要解决这一问题需采用自适应控制。

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The poor are very wonderful people. One evening my sisters and I went out and picked up four people from the street. One of them  31  a most terrible condition. I told my sisters, "You  32  the other three. I take care of this one who looks  33 .”So I did for her all that my love can do.I  34  her in bed, and there was such a beautiful smile on her face. She took hold of my hand as she   35  ‘’Thank you" and then she died. I could not help but examined my heart before her. I asked myself  36  I would say if I was in her place. My answer was very simple.1 would say I was hungry, cold, homeless, and I was dying, or something else, but she gave me her  37  love. Then she died with a smile on her face.
I am going to try to make a home for many people who have no home. Because I believe that love begins at home, and if we can create a home for the poor, I think that  38  love will spread(延伸、撒开).Through this love we will be able to bring peace to the poor. So let us always meet  39  with a smile, for the smile is the  40  of love, and once we begin to love each other naturally, we will do something for others.
小题1:
A.were inB.was inC.were withD.was with
小题2:
A.look forB.care aboutC.catch up withD.look after
小题3:
A.worseB.strongerC.betterD.healthier
小题4:
A.gaveB.threwC.putD.pushed
小题5:
A.spokeB.toldC.saidD.shouted
小题6:
A.whichB.whatC.whenD.how
小题7:
A.gratefulB.carefulC.hopefulD.powerful
小题8:
A.less and lessB.little and little
C.more and moreD.fewer and fewer
小题9:
A.the othersB.the otherC.anotherD.each other
小题10:
A.beginB.beginningC.endD.ending
问答题 简答题