搜索
案例：电动机自由停车的时间较长，随惯性大小而不同，而某些生产机械要求迅速、准确地停车，如镗床、车床的主电动机需快速停车；起重机为使重物停位准确及现场安全要求，也必须采用快速、可靠的制动方式制动：机械制动和电气制动电气制动：在电动机转子上加一个与转向相反的制动电磁转矩，使电动机转速迅速下降，或稳定在另一转速反接制动能耗制动常用三相异步电动机制动控制电路一、机械制动当电动机的定子绕组断电后，利用机械装置使电动机立即停转。机械制动电磁抱闸制动器MZD1系列交流单相制动电磁铁TJ2系列闸瓦制动器1－线圈2－衔铁3－铁心4－弹簧5－闸轮6－杠杆7－闸瓦8－轴电磁抱闸制动器结构示意图电磁抱闸制动器工作原理示意图1－弹簧2－衔铁3－线圈4－铁心5－闸轮6－闸瓦7－杠杆电源电磁抱闸断电制动控制线路L1L2L3FU1FU2KMFRSB2SB1KMYBQSKMFRM3～电磁抱闸断电制动控制线路L1L2L3FU1FU2KMSB2SB1KMYBQSKM合上电源开关QSFRFRM3～电磁抱闸断电制动控制线路L1L2L3FU1FU2KMSB2SB1KMYBQSKM按下SB2KM线圈得电FRFRM3～电磁抱闸断电制动控制线路L1L2L3FU1FU2KMSB2SB1KMYBQSKMKM1自锁触头闭合,自锁，松开SB2电磁抱闸线圈YB得电，使抱闸的闸瓦与闸轮分开KM1主触头闭合,电动机起动运行FRFRM3～电磁抱闸断电制动控制线路L1L2L3FU1FU2KMSB2SB1KMYBQSKM停:按SB1，接触器KM失电释放电磁抱闸线圈YB也失电，在弹簧的作用下，闸瓦与闸轮紧紧抱住FRFRM3～电磁抱闸通电制动控制线路L1L2L3FU1FU2KM1FRSB1SB2KM1YBQSKM1FRM3～KM2KM2KM1电路组成分析电磁抱闸通电制动控制线路L1L2L3FU1KM1SB1SB2KM1QSKM1KM2KM1合上电源开关QSKM2FRFRM3～FU2YBKM2电磁抱闸通电制动控制线路L1L2L3FU1KM1SB1SB2KM1QSKM1KM2KM1按下SB1KM1线圈得电KM2FRFRM3～FU2YBKM2电磁抱闸通电制动控制线路L1L2L3FU1KM1SB1SB2KM1QSKM1KM2KM1KM1自锁触头闭合,自锁，松开SB1KM1联锁触头断开，KM1主触头闭合电动机起动运行电磁抱闸线圈YB不得电KM2FRFRM3～YBKM2FU2电磁抱闸通电制动控制线路L1L2L3FU1KM1SB1SB2KM1QSKM1KM2KM1KM2停：按下SB2KM1线圈失电释放KM2线圈得电，KM2主触头闭合电磁抱闸线圈YB得电，使闸瓦与闸轮紧紧抱住FRFRM3～YBFU2二、电气制动电动机产生一个和电动机实际旋转方向相反的电磁转矩，使电动机迅速停转。（一）能耗制动电动机切断交流电源后，立即在定子线组的任意两相中通入直流电，利用转子感应电流受静止磁场的作用以达到制动目的。M3～L1L2L3KM1FRSB1KM1SB2KM2KM1KM2FRKM1KTKM2VUWQSFU1FU2KTKT单向启动能耗制动自动控制线路KM2电路组成分析定子绕组直流电通路KM2VL1L2L3KM1SB1KM1SB2KM2KM1KM2KM1KTKM2QSFU1FU2KTKTKM2合上电源开关QS按下SB1KM1线圈得电单向启动能耗制动自动控制线路KM2VM3～FRFRVUWL1L2L3KM1SB1KM1SB2KM2KM1KM2KM1KTKM2QSFU1FU2KTKTKM2KM1自锁触头闭合KM1主触头闭合KM1联锁触头分断单向启动能耗制动自动控制线路KM2VM3～FRFRVUWL1L2L3KM1SB1KM1SB2KM2KM1KM2KM1KTKM2KM2VQSFU1FU2KTKTKM2按下SB2KM1线圈失电KM1自锁触头分断KM1主触头分断KM1联锁触头闭合KM2线圈得电KT线圈得电单向启动能耗制动自动控制线路M3～FRFRVUWL1L2L3KM1SB1KM1SB2KM2KM1KM2KM1KTKM2KM2QSFU1FU2KTKTKM2KM2自锁触头闭合KM2主触头分断闭合电动机半波能耗制动KM2联锁触头分断KT瞬时闭合触头闭合松开SB2单向启动能耗制动自动控制线路VM3～FRFRVUWL1L2L3KM1SB1KM1SB2KM2KM1KM2KM1KTKM2KM2VQSFU1FU2KTKTKM2KT延时断开触头延时分断KM2线圈失电KT线圈失电各触头复位单向启动能耗制动自动控制线路M3～FRFRVUWFU2FRSB1KM1SB2KM1KM2KTKTKTKM2KM2KM1M3～L1L2L3FU1KM1QSFU3VCTCFRRKM2VUW3KM2有变压器桥式整流能耗制动控制线路电路组成分析FU2SB1KM1SB2KM1KM2KTKTKTKM2KM2KM1L1L2L3FU1KM1QSFU3VCTCRKM2VUW3KM2有变压器桥式整流能耗制动控制线路合上电源开关QS按下SB1KM1线圈得电FRM3～FRFU2SB1KM1SB2KM1KM2KTKTKTKM2KM2KM1L1L2L3FU1KM1QSFU3VCTCRKM2VUW3KM2有变压器桥式整流能耗制动控制线路KM1自锁触头闭合KM1主触头闭合KM1联锁触头分断松开SB1FRM3～FRFU2SB1KM1SB2KM1KM2KTKTKTKM2KM2KM1L1L2L3FU1KM1QSFU3VCTCRKM2VUW3KM2有变压器桥式整流能耗制动控制线路按下SB1KM1线圈失电KM1自锁触头分断KM1主触头分断KM1联锁触头闭合KM2线圈得电KT线圈得电FRM3～FRFU2SB1KM1SB2KM1KM2KTKTKTKM2KM2KM1L1L2L3FU1KM1QSFU3VCTCRKM2VUW3KM2有变压器桥式整流能耗制动控制线路KM2自锁触头闭合KM2主触头分断闭合电动机半波能耗制动KM2联锁触头分断KT瞬时闭合触头闭合松开SB1FRM3～FRFU2SB1KM1SB2KM1KM2KTKTKTKM2KM2KM1L1L2L3FU1KM1QSFU3VCTCRKM2VUW3KM2有变压器桥式整流能耗制动控制线路KT延时断开触头延时分断KM2线圈失电KT线圈失电各触头复位FRM3～FR（二）反接制动１.反接制动原理在停车时，把电动机反接，则其定子旋转磁场便反向旋转，在转子上产生的电磁转矩亦随之变为反向，成为制动转矩。反接制动单向启动反接制动控制M3～L1L2L3FU1FU2KM1KM2FRSB1KM1SB2KM2KM1KM2FRQSＲKM1nKSKM2KS单向启动反接制动控制L1L2L3FU1FU2KM2SB1KM1SB2QSＲKM1nKSKM2KS合上电源开关QSM3～KM1FRKM2FRKM1KM2单向启动反接制动控制L1L2L3FU1FU2KM2SB1KM1SB2KM1KM2QSＲKM1nKSKM2KS按下SB1KM1线圈得电M3～KM1FRKM2FR单向启动反接制动控制L1L2L3FU1FU2KM2SB1KM1SB2KM1KM2QSＲKM1KSKM2KSnKM1自锁触头闭合,自锁，松开SB1KM1主触头闭合,电动机起动，运行在转速高到一定值时，KS闭合M3～KM1FRKM2FR单向启动反接制动控制L1L2L3FU1FU2KM2SB1KM1SB2KM1KM2QSＲKM1KM2KSn停：按下SB2KM1失电释放KM2线圈得电，KM2主触头闭合，电动机串联电阻反接，反接制动KM2自锁触头闭合M3～KM1FRKM2FRKS单向启动反接制动控制L1L2L3FU1FU2KM2SB1KM1SB2KM1KM2QSＲKM1KM2KSn停：松开SB2继续反接制动M3～KM1FRKM2FRKS单向启动反接制动控制L1L2L3FU1FU2KM2SB1KM1SB2KM1KM2QSＲnKM2KS当转速降低到一定值时，KS断开KM2线圈失电，各触头复位M3～KM1FRKM2FRKM1KS