課題七 多速異步電動機的控制線路,三相異步電動機的轉(zhuǎn)速公式 可知，改變異步電動機轉(zhuǎn)速可通過三種方法來實現(xiàn)： 一是改變電源頻率f1； 二是改變轉(zhuǎn)差率s； 三是改變磁極對數(shù)p。 改變異步電動機的磁極對數(shù)調(diào)速稱為變極調(diào)速。變極調(diào)速是通過改變定子繞組的連接方式來實現(xiàn)的，它是有級調(diào)速，且只適用于籠型異步電動機。 磁級對數(shù)可改變的電動機稱為多速電動機。常見的多速電動機有雙速、三速、四速等。,1,U1,U2,V2,W1,W2,W2,L1 L2 L3,U2 V2 W2,U1 V1 W1,V2,V1,U2,L1 L2 L3,U1 V1 W1,U2 V2 W2,U1,V1,W1,1.雙速異步電動機定子繞組的連接,一、雙速異步電動機的控制線路,2,雙速異步電動機定子繞組的/YY連接圖中，三相定子繞組接成形，由三個連接點接出三個出線端U1，V1，W1，從每相繞組的中點各接出一個出線端U2，V2，W2，這樣定子繞組共有6個出線端。通過改變這6個出線端與電源的連接方式，就可以得到兩種不同的轉(zhuǎn)速。低速工作時，把三相電源分別接在出線端U1，V1，W1上，另外三個出線端U2，V2，W2空著不接，電動機定子繞組接成形，磁極為4極，同步轉(zhuǎn)速為1500R/MIN。電動機高速工作時，要把三個出線端U1，V1，W1并接在一起，三相電源分別接到另外三個出線端U2，V2，W2上，這時電動機定子繞組接成YY形，磁極為2極，同步轉(zhuǎn)速為3000R/MIN。可見雙速電動機高速運轉(zhuǎn)時的轉(zhuǎn)速是低速運轉(zhuǎn)轉(zhuǎn)速的兩倍。要注意的是，雙速電動機定子繞組從一種接法改變?yōu)榱硪环N接法時，必須把電源相序反接，以保證電動機的旋轉(zhuǎn)方向不變。,3,L1L2L3,KH,SB1,KM1,KM2,SB2,KM1,QS,FU1,FU2,KH,KM1,KM2,KM3,SB3,KM3 KM2,KM3 KM2,KM1,KM3,U1,V1,W1,U2,V2,W2,低速,高速YY,2.按鈕和接觸器控制雙速電動機,4,L1L2L3,SB1,KM1,SB2,KM1,FU1,KM1,KM2,KM3,SB3,KM3 KM2,KM3 KM2,U1,V1,W1,U2,V2,W2,合上QS 按下SB1 KM1線圈得電,KM2,QS,FU2,KM1,KM3,低速,高速YY,KH,KH,2.按鈕和接觸器控制雙速電動機,5,L1L2L3,SB1,KM1,SB2,KM1,FU1,KM1,KM2,KM3,SB3,KM3 KM2,KM3 KM2,U1,V1,W1,U2,V2,W2,KM1觸頭動作 電動機 聯(lián)接,低速啟動,KM2,QS,FU2,KM1,KM3,低速,高速YY,KH,KH,2.按鈕和接觸器控制雙速電動機,6,L1L2L3,SB1,KM1,SB2,KM1,FU1,KM1,KM2,KM3,SB3,KM3 KM2,KM3 KM2,U1,V1,W1,U2,V2,W2,按下SB2 KM1線圈失電KM2,KM3線圈得電,KM2,QS,FU2,KM1,KM3,低速,高速YY,KH,KH,2.按鈕和接觸器控制雙速電動機,7,L1L2L3,SB1,KM1,SB2,KM1,FU1,KM1,KM2,KM3,SB3,KM3 KM2,KM3 KM2,U1,V1,W1,U2,V2,W2,KM2,KM3觸頭動作 電動機YY聯(lián)接,電動機高速運行,KM2,QS,FU2,KM1,KM3,低速,高速YY,KH,KH,2.按鈕和接觸器控制雙速電動機,8,低速,L1L2L3,SB1,KM1,SB2,KM1,FU1,KM1,KM2,KM3,SB3,KM3 KM2,KM3 KM2,U1,V1,W1,U2,V2,W2,松開SB2 電動機繼續(xù)高速運行,KM2,QS,FU2,KM1,KM3,高速YY,KH,KH,2.按鈕和接觸器控制雙速電動機,9,L1L2L3,KH,SB1,KM1,KM2,SB2,KM1,QS,FU1,FU2,KM1,KM2,KM3,SB3,KM3 KM2,KM1,KM3,U1,V1,W1,U2,V2,W2,低速,高速YY,3.時間繼電器控制雙速電動機,KT,KM1,KT,KT,KT,電路組成分析：用時間繼電器控制雙速電動機低速啟動高速運轉(zhuǎn)，時間繼電器KT控制電動機形啟動時間和-YY的啟動換接運轉(zhuǎn)。,KH,10,L1L2L3,SB1,KM1,KM2,SB2,KM1,QS,FU1,FU2,KM1,KM2,KM3,SB3,KM3 KM2,KM1,KM3,U1,V1,W1,U2,V2,W2,KT,KM1,合上QS 按下SB1 KM1線圈得電,KT,KT,KT,低速起動 高速運行,低速,高速YY,KH,KH,3.時間繼電器控制雙速電動機,11,L1L2L3,SB1,KM1,KM2,SB2,KM1,QS,FU1,FU2,KM1,KM2,KM3,SB3,KM3 KM2,KM1,KM3,U1,V1,W1,U2,V2,W2,KT,KM1,KM1觸頭動作 電動機三角形聯(lián)接低速起動 松開SB1繼續(xù)低速運行,KT,KT,KT,低速起動 高速運行,低速,高速YY,KH,KH,3.時間繼電器控制雙速電動機,12,L1L2L3,SB1,KM1,KM2,SB2,KM1,QS,FU1,FU2,KM1,KM2,KM3,SB3,KM3 KM2,KM1,KM3,U1,V1,W1,U2,V2,W2,KT,KM1,按下SB2 KM1線圈得電 KT線圈得電,KT,KT,KT,低速起動 高速運行,低速,高速YY,KH,KH,3.時間繼電器控制雙速電動機,13,L1L2L3,SB1,KM1,KM2,SB2,KM1,QS,FU1,FU2,KM1,KM2,KM3,SB3,KM3 KM2,KM1,KM3,U1,V1,W1,U2,V2,W2,KT,KM1,KM1，KT各觸頭動作電動機低速起動 松開SB2,KT,KT,KT,低速起動 高速運行,低速,高速YY,KH,KH,3.時間繼電器控制雙速電動機,14,L1L2L3,SB1,KM1,KM2,SB2,KM1,QS,FU1,FU2,KM1,KM2,KM3,SB3,KM3 KM2,KM1,KM3,U1,V1,W1,U2,V2,W2,KT,KM1,經(jīng)KT整定時間 KT延時觸頭動作, KM1線圈斷電 KM2,KM3線圈得電 動作電動機 高速運行,KT,KT,KT,低速起動 高速運行,低速,高速YY,KH,KH,3.時間繼電器控制雙速電動機,15,L1L2L3,SB1,KM1,KM2,SB2,KM1,QS,FU1,FU2,KM1,KM2,KM3,SB3,KM3 KM2,KM1,KM3,U1,V1,W1,U2,V2,W2,KT,KM1,KT,KT,KT,停: 按下SB3 或過載,低速起動 高速運行,低速,高速YY,KH,KH,3.時間繼電器控制雙速電動機,16,三速電動機定子繞組接線圖,中速Y接法 高速YY接法,二、三速異步電動機的控制線路,三速電動機的兩套定子繞組,低速接法,17,三速異步時機有兩套定子繞組，分兩層安放在定子槽內(nèi)，第一套繞組（雙速）有七個出線端U1，VI，W1，U3，U2，V2，W2，可作或YY連接；第二套繞組（單速）有三個出線端U4，V4，W4，只作Y形連接。當(dāng)分別改變兩套定子繞組的連接方式（即改變磁極對數(shù)）時，電動機就可得到三種不同的轉(zhuǎn)速。 三速異步電動機定子繞組的接線方法：W1和U3出線端分開的目的是當(dāng)電動機定子繞組接Y形中速運轉(zhuǎn)時，避免在形接法的定子繞組中產(chǎn)生感應(yīng)電流。,18,1.接觸器控制三速電動機的控制線路 形低速 Y形中速 YY形高速,19,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM3,KM1,KM2,SB4,KM1,KM2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,KH,KH,電路組成分析,20,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM3,KM1,KM2,SB4,KM1,KM2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,合上電源開關(guān)QS 按下SB1 KM1線圈得電 電動機接成 低速啟動,KH,KH,21,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM3,KM1,KM2,SB4,KM1,KM2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,松開SB1 電動機繼續(xù) 低速啟動,運行,KH,KH,22,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM3,KM1,KM2,SB4,KM1,KM2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,先按SB4 KM1線圈失電 電動機斷電 再按SB2 KM2線圈得電 電動機Y聯(lián)接,中速運行,KH,KH,23,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM3,KM1,KM2,SB4,KM1,KM2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,松開SB2 電動機Y聯(lián)接,繼續(xù) 中速運行,KH,KH,24,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM3,KM1,KM2,SB4,KM1,KM2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,先按SB4 KM2線圈失電 電動機斷電 再按SB3 KM3,KM4線圈得電 電動機YY聯(lián)接,高速運行,KH,KH,25,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM1,KM2,SB4,KM1,KM2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,先按SB4 KM2線圈失電 電動機斷電 再按SB3 KM3,KM4線圈得電 電動機YY聯(lián)接,高速運行,KH,KH,26,2.時間繼電器自動控制三速電動機 的控制線路 用時間繼電器控制三速電動機的電路圖中，SB1、KM1控制電動機接法下低速啟動運轉(zhuǎn)；SB2、KT1、KM2控制電動機從接法下低速啟動到Y(jié)接法下中速運轉(zhuǎn)的自動變換；SB3、KT1、KT2、KM3控制電動機從接法下低速啟動到Y(jié)中速過渡到Y(jié)Y接法下高速運轉(zhuǎn)的自動變換。,27,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM1,KM2,SB4,KM1,KT2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,KH,KH,電路組成分析,KT1,KT2,KT1,KT1,KM2,KM3,KM2,KM3,KT2,KT1,KT2,28,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM1,KM2,SB4,KM1,KT2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,低速啟動運轉(zhuǎn): 合上QS,按下SB1 KM1線圈得電，KM1的所有觸頭動作，電動機得電低速啟動運轉(zhuǎn),KT1,KT2,KT1,KT1,KM2,KM3,KM2,KM3,KT2,KT1,KT2,KH,KH,29,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM1,KM2,SB4,KM1,KT2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,低速啟動運轉(zhuǎn): 松開SB1 電動機繼續(xù)低速運行,KT1,KT2,KT1,KT1,KM2,KM3,KM2,KM3,KT2,KT1,KT2,KH,KH,30,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM1,KM2,SB4,KM1,KT2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,KH,KH,KT1,KT2,KT1,KT1,KM2,KM3,KM2,KM3,KT2,KT1,KT2,形低速啟動 Y形中速運轉(zhuǎn): 按下SB2 KT1線圈得電,31,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM1,KM2,SB4,KM1,KT2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,KT1,KT2,KT1,KT1,KM2,KM3,KM2,KM3,KT2,KT1,KT2,形低速啟動 Y形中速運轉(zhuǎn): 時間繼電器瞬時閉合觸頭閉合 KM1線圈得電,KH,KH,32,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM1,KM2,SB4,KM1,KT2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,KT1,KT2,KT1,KT1,KM2,KM3,KM2,KM3,KT2,KT1,KT2,形低速啟動運轉(zhuǎn)Y形中速運轉(zhuǎn): KM1觸頭動作 電動機低速啟動 松開SB2,KH,KH,33,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM1,KM2,SB4,KM1,KT2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,KT1,KT2,KT1,KT1,KM2,KM3,KM2,KM3,KT2,KT1,KT2,形低速啟動運轉(zhuǎn)Y形中速運轉(zhuǎn): 經(jīng)KT1整定時間 KT1延時斷開觸頭分?jǐn)?KM1線圈失電 KT1延時閉合觸頭閉合,KM2線圈得電,KH,KH,34,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM1,KM2,SB4,KM1,KT2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,KT1,KT2,KT1,KT1,KM2,KM3,KM2,KM3,KT2,KT1,KT2,形低速啟動運轉(zhuǎn)Y形中速運轉(zhuǎn): KM2觸頭動作電動機Y形聯(lián)接,中速運行,KH,KH,35,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM1,KM2,SB4,KM1,KT2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,YY高速運轉(zhuǎn)： 按下SB3 KT2線圈得電,KT1,KT2,KT1,KT1,KM2,KM3,KM2,KM3,KT2,KT1,KT2,KH,KH,36,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM1,KM2,SB4,KM1,KT2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,KT1,KT2,KT1,KT1,KM2,KM3,KM2,KM3,KT2,KT1,KT2,KT2瞬時觸頭閉合 KT1線圈得電,KH,KH,37,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM1,KM2,SB4,KM1,KT2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,KT1,KT2,KT1,KT1,KM2,KM3,KM2,KM3,KT2,KT1,KT2,KT1瞬時觸頭閉合 KM1線圈得電,KH,KH,38,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM1,KM2,SB4,KM1,KT2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,KT1,KT2,KT1,KT1,KM2,KM3,KM2,KM3,KT2,KT1,KT2,KM1觸頭動作 形低速啟動 松開SB3,KH,KH,39,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM1,KM2,SB4,KM1,KT2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,KT1,KT2,KT1,KT1,KM2,KM3,KM2,KM3,KT2,KT1,KT2,經(jīng)KT1整定時間 KT1延時斷開觸頭分?jǐn)? KM1線圈失電 KT1延時閉合觸頭閉合, KM2線圈得電,KH,KH,40,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM1,KM2,SB4,KM1,KT2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,KT1,KT2,KT1,KT1,KM2,KM3,KM2,KM3,KT2,KT1,KT2,KM2觸頭動作, 電動機接成Y形, 中速過渡,KH,KH,41,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM1,KM2,SB4,KM1,KT2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,KT1,KT2,KT1,KT1,KM2,KM3,KM2,KM3,KT2,KT1,KT2,經(jīng)KT2整定時間KT2延時斷開觸頭分?jǐn)?KM2線圈失電 KT2延時閉合觸頭閉合, KM3,KM4線圈得電,KH,KH,42,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM1,KM2,SB4,KM1,KT2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,KT1,KT2,KT1,KT1,KM2,KM3,KM2,KM3,KT2,KT1,KT2,KM3,KM4觸頭動作 電動機YY形聯(lián)接 高速成運轉(zhuǎn) KT1,KT2線圈失電 觸頭復(fù)位,KH,KH,43,L1L2L3,KM1,QS,FU1,FU2,KM2,KM1,低速,Y 中速 YY 高速,KM3,KM3,KM2,KM3,KM1,KM1,KM2,SB4,KM1,KT2,SB2,SB3,SB1,U3,W1,V1,U1,V2,V4,U4,U2,W2,W4,KM4,KM4,KM4,KM2,KM3,KM4,停: 按下SB4,KT1,KT2,KT1,KT1,KM2,KM3,KM2,KM3,KT2,KT1,KT2,KH,KH,44,