繞線轉(zhuǎn)子異步電動機(jī)的控制線路

1、中間繼電器的符號,復(fù) 習(xí),2.電流繼電器 反映輸入量為電流的繼電器叫做電流繼電器。 電流繼電器的線圈串聯(lián)在被測電路中， 當(dāng)通過線圈的電流達(dá)到預(yù)定值時，其觸頭動作。,復(fù) 習(xí),（1）過電流繼電器 當(dāng)通過繼電器的電流超過預(yù)定值時就動作的繼電器稱為過電流繼電器。 （2）欠電流繼電器 當(dāng)通過繼電器的電流減小到低于其整定值時就動作的繼電器稱為欠電流繼電器。,復(fù) 習(xí),課題八：繞線轉(zhuǎn)子異步電動機(jī)的控制線路（一）,學(xué)習(xí)目標(biāo)： 熟悉繞線轉(zhuǎn)子異步電動機(jī)控制線路的構(gòu)成和工作原理。,課題八：繞線轉(zhuǎn)子異步電動機(jī)的控制線路,一、轉(zhuǎn)子繞組串接電阻啟動控制線路 1.轉(zhuǎn)子串接三相電阻啟動原理 2.按鈕操作控制線路 3.時間繼電器

2、自動控制線路 4.電流繼電器自動控制線路 二、轉(zhuǎn)子繞組串接變阻器啟動控制線路 1.頻敏變阻器 2.轉(zhuǎn)子繞組串接頻敏變阻器啟動控制線路 三、凸輪控制器控制線路,YR系列 符號,繞線轉(zhuǎn)子三相異步電動機(jī)，可以通過滑環(huán)在轉(zhuǎn)子繞組中串接電阻來改善電動機(jī)的機(jī)械特性，從而達(dá)到減小啟動電流、增大啟動轉(zhuǎn)矩以及調(diào)節(jié)轉(zhuǎn)速的目的。,繞線轉(zhuǎn)子異步電動機(jī)控制線路,1、應(yīng)用場合： 在要求啟動轉(zhuǎn)矩較大且有一定調(diào)速要求的場合，如：起重機(jī)、卷揚機(jī)等，常常采用三相繞線轉(zhuǎn)子異步電動機(jī)拖動。 2、分類： （1）轉(zhuǎn)子繞組串接電阻啟動控制線路 （2）轉(zhuǎn)子繞組串接頻敏變阻器控制線路 （3）凸輪控制器控制線路,一、轉(zhuǎn)子繞組串接電阻啟動控制線路

3、,1.轉(zhuǎn)子串接三相電阻啟動原理 啟動時，在轉(zhuǎn)子回路串入作Y形連接、分級切換的三相啟動電阻器，以減小啟動電流、增加啟動轉(zhuǎn)矩。隨著電動機(jī)轉(zhuǎn)速的升高，逐級減小可變電阻。啟動完畢后，切除可變電阻器，轉(zhuǎn)子繞組被直接短接，電動機(jī)便在額定狀態(tài)下運行。,轉(zhuǎn)子串接三相對稱電阻器,轉(zhuǎn)子串接三相不對稱電阻器,2.按鈕操作控制線路 特點： 工作原理簡單，操作不便，工作的安全性和可靠性較差，所以生產(chǎn)實際中不常用。,L1L2L3,FU1,KM1,FU2,KH,SB5,QS,SB1,KM2,KM3,KM,KM1,KM3,KM2,KM1,KM3,KM2,KM,R1,R2,R3,KH,SB2,SB3,SB4,電路組成分析,KM

4、,L1L2L3,KM1,SB5,SB1,KM2,KM3,KM,KM1,KM3,KM2,KM1,KM,KM3,KM2,KM,R1,R2,R3,SB2,SB3,SB4,合上QS 按下SB1 繞線轉(zhuǎn)子串聯(lián)全部電阻啟動,FU1,FU2,QS,KH,KH,L1L2L3,KM1,SB5,SB1,KM2,KM3,KM,KM1,KM3,KM2,KM1,KM,KM3,KM2,KM,R1,R2,R3,SB2,SB3,SB4,按下SB2 KM1線圈得電 KM1觸頭閉合 繞線轉(zhuǎn)子串聯(lián)R2,R3啟動,FU1,FU2,QS,KH,KH,L1L2L3,KM1,SB5,SB1,KM2,KM3,KM,KM1,KM3,KM2,K

5、M1,KM,KM3,KM2,KM,R1,R2,R3,SB2,SB3,SB4,按下SB3 KM2線圈得電 KM2觸頭閉合 繞線轉(zhuǎn)子串聯(lián)R3啟動,FU1,FU2,QS,KH,KH,L1L2L3,KM1,SB5,SB1,KM2,KM3,KM,KM1,KM3,KM2,KM1,KM,KM3,KM2,KM,R1,R2,R3,SB2,SB3,SB4,按下SB4 KM3線圈得電 KM3觸頭閉合 繞線轉(zhuǎn)子切除全部電阻運行,FU1,FU2,QS,KH,KH,L1L2L3,KM1,SB5,SB1,KM2,KM3,KM,KM1,KM3,KM2,KM1,KM,KM3,KM2,KM,SB2,SB3,SB4,松開SB4 電

6、動機(jī)繼續(xù)運行,R1,R2,R3,FU1,FU2,QS,KH,KH,3.時間繼電器自動控制線路 特點： 線路利用三個時間繼電器和三個接觸器的相互 配合來依次自動切除轉(zhuǎn)子繞組中的三級電阻,L1L2L3,FU1,KM1,FU2,KH,SB2,QS,SB1,KM2,KM3,KM,KM,KT3,KM3,KM2,KM1,KM3,KM2,KM1,KM,R1,KT1,KT2,KT3,R2,R3,KM,KM1,KM2,KM3,KM3,KT1,KT2,KH,電路組成分析,L1L2L3,SB2,SB1,KM3,KM,KM,KT3,KM2,KM1,KM3,KM2,KM1,R1,R2,R3,KM,KM1,KM2,KM3

7、,KM3,KT1,KT2,合上QS 按下SB1 KM線圈得電,KM1,KM2,KM3,KM,KT1,KT2,KT3,FU1,FU2,KH,QS,KH,L1L2L3,M 3,SB2,SB1,KM3,KM,KM,KT3,KM2,KM1,KM3,KM2,KM1,R1,R2,R3,KM,KM1,KM2,KM3,KM3,KT1,KT2,KM觸頭閉合 繞線轉(zhuǎn)子串聯(lián)全部電阻啟動 KT1線圈得電,KM1,KM2,KM3,KM,KT1,KT2,KT3,FU1,FU2,KH,QS,KH,L1L2L3,M 3,SB2,SB1,KM3,KM,KM,KT3,KM2,KM1,KM3,KM2,KM1,R1,R2,R3,KM

8、,KM1,KM2,KM3,KM3,KT1,KT2,KT1延時閉合觸頭閉合 KM1線圈得電,KM1,KM2,KM3,KM,KT1,KT2,KT3,FU1,FU2,KH,QS,KH,L1L2L3,M 3,SB2,SB1,KM3,KM,KM,KT3,KM2,KM1,KM3,KM2,KM1,R1,R2,R3,KM,KM1,KM2,KM3,KM3,KT1,KT2,KM1觸頭閉合 繞線轉(zhuǎn)子串聯(lián)R2,R3啟動 KT2線圈得電,KM1,KM2,KM3,KM,KT1,KT2,KT3,FU1,FU2,KH,QS,KH,L1L2L3,M 3,SB2,SB1,KM3,KM,KM,KT3,KM2,KM1,KM3,KM2

9、,KM1,R1,R2,R3,KM,KM1,KM2,KM3,KM3,KT1,KT2,KT2延時閉合觸頭閉合 KM2線圈得電,KM1,KM2,KM3,KM,KT1,KT2,KT3,FU1,FU2,KH,QS,KH,L1L2L3,M 3,SB2,SB1,KM3,KM,KM,KT3,KM2,KM1,KM3,KM2,KM1,R1,R2,R3,KM,KM1,KM2,KM3,KM3,KT1,KT2,KM2觸頭閉合 繞線轉(zhuǎn)子串聯(lián)R3啟動 KT3線圈得電,KM1,KM2,KM3,KM,KT1,KT2,KT3,FU1,FU2,KH,QS,KH,L1L2L3,M 3,SB2,SB1,KM3,KM,KM,KT3,KM

10、2,KM1,KM3,KM2,KM1,R1,R2,R3,KM,KM1,KM2,KM3,KM3,KT1,KT2,KT3延時閉合觸頭閉合 KM3線圈得電,KM1,KM2,KM3,KM,KT1,KT2,KT3,FU1,FU2,KH,QS,KH,L1L2L3,M 3,SB2,SB1,KM3,KM,KM,KT3,KM2,KM1,KM3,KM2,KM1,R1,R2,R3,KM,KM1,KM2,KM3,KM3,KT1,KT2,KM3觸頭閉合 繞線轉(zhuǎn)子切除全部電阻運行,KM1,KM2,KM3,KM,KT1,KT2,KT3,FU1,FU2,KH,QS,KH,L1L2L3,M 3,SB2,SB1,KM3,KM,KM

11、,KT3,KM2,KM1,KM3,KM2,KM1,R1,R2,R3,KM,KM1,KM2,KM3,KM3,KT1,KT2,KM3動斷觸頭斷開 KT1線圈失電 KT1觸頭斷開 KM1線圈失電 KM1觸頭動作 KT2線圈失電 KT2觸頭動作 KM2線圈失電 KM2觸頭動作 KT3線圈失電 KT3觸頭斷開 電動機(jī)繼續(xù)運轉(zhuǎn),KM1,KM2,KM3,KM,KT1,KT2,KT3,FU1,FU2,KH,QS,KH,思考,？將三個觸器的輔助常閉觸頭與啟動按鈕串接，這樣做的目的是什么？,思考答案,目的： 如果三個接觸器中的任何一個因觸頭熔焊或機(jī)械故障而不能正常釋放時，即使按下啟動按鈕，控制電路也不會得電，電動

12、機(jī)就不會接通電源啟動運行。,4.電流繼電器自動控制電路 繞線轉(zhuǎn)子異步電動機(jī)剛啟動時轉(zhuǎn)子電流較大，隨著電動機(jī)轉(zhuǎn)速的增大，轉(zhuǎn)子電流逐漸減小，根據(jù)這一特性，可以利用電流繼電器自動控制接觸器來逐級切除轉(zhuǎn)子回路的電阻。,L1L2L3,FU1,3,FU2,KH,SB2,QS,SB1,KM,KM,KA1,KM2,KM,R2,R1,KA2,KH,KA1,KA,KM3,KA3,R3,KA3,KM1,KM1,KM2,KM3,KA2,KA,KM,KM1,KM2,KM3,電路組成分析,L1L2L3,FU1,3,SB2,SB1,KM,KM,KA1,KM2,KM,R2,R1,KA2,KA1,KA,KM3,KA3,R3,K

13、A3,KM1,KM1,KM2,KM3,KA2,KA,KM,KM1,KM2,KM3,合上QS 按下SB1 KM線圈得電,FU2,KH,QS,KH,L1L2L3,FU1,3,SB2,SB1,KM,KM,KA1,KM2,KM,R2,R1,KA2,KA1,KA,KM3,KA3,R3,KA3,KM1,KM1,KM2,KM3,KA2,KA,KM,KM1,KM2,KM3,KM觸頭閉合 繞線轉(zhuǎn)子串聯(lián)全部電阻啟動 K線圈得電,FU2,KH,QS,KH,L1L2L3,FU1,3,SB2,SB1,KM,KM,KA1,KM2,KM,R2,R1,KA2,KA1,KA,KM3,KA3,R3,KA3,KM1,KM1,KM2

14、,KM3,KA2,KA,KM,KM1,KM2,KM3,KA常開觸頭閉合,為KM1,KM2,KM3得電作準(zhǔn)備 因啟動電流大KA1,KA2,KA3的動斷觸頭斷開,繼續(xù)串聯(lián)全部電阻啟動,FU2,KH,QS,KH,L1L2L3,FU1,3,SB2,SB1,KM,KM,KA1,KM2,KM,R2,R1,KA2,KA1,KA,KM3,KA3,R3,KA3,KM1,KM1,KM2,KM3,KA2,KA,KM,KM1,KM2,KM3,因速度加快，電流減小， KA1欠電流,動斷觸頭閉合，,KM1線圈得電KM1觸頭閉合,切除第一組電阻R1 串聯(lián)R2,R3繼續(xù)啟動,FU2,KH,QS,KH,L1L2L3,FU1,3

15、,SB2,SB1,KM,KM,KA1,KM2,KM,R2,R1,KA2,KA1,KA,KM3,KA3,R3,KA3,KM1,KM1,KM2,KM3,KA2,KA,KM,KM1,KM2,KM3,因速度再加快電流繼續(xù)減小 ， KA2欠電流, 動斷觸頭閉合KM2線圈得電KM2觸頭閉合，切除第二組電阻R2 串聯(lián)R3繼續(xù)啟動,FU2,KH,QS,KH,L1L2L3,FU1,3,SB2,SB1,KM,KM,KA1,KM2,KM,R2,R1,KA2,KA1,KA,KM3,KA3,R3,KA3,KM1,KM1,KM2,KM3,KA2,KA,KM,KM1,KM2,KM3,因速度再加快電流繼續(xù)減小 KA3欠電流, 動斷觸頭閉合KM3線圈得電KM3觸頭閉合切除全部電阻, 電動機(jī)啟動完畢，全速運行,FU2,KH,QS,KH,思考,？中間繼電器的作用？,思考答案：,中間繼電器的作用是保證電動機(jī)在轉(zhuǎn)子電路中接入全部電阻的情況下開始