风(feng)机电机轴承发热原因分析和应对措施

由于静电(dian)(dian)耦合，电(dian)(dian)机(ji)(ji)(ji)各部分(fen)(fen)间都(dou)有或大(da)或小(xiao)的分(fen)(fen)布电(dian)(dian)容，构成电(dian)(dian)机(ji)(ji)(ji)定(ding)(ding)子(zi)上共模(mo)电(dian)(dian)流(liu)的泄(xie)放(fang)路(lu)径(jing)(jing)。大(da)部分(fen)(fen)共模(mo)电(dian)(dian)流(liu)经(jing)(jing)定(ding)(ding)子(zi)—机(ji)(ji)(ji)壳(qiao)(qiao)—地—变(bian)频器(qi)外壳(qiao)(qiao)这(zhei)一(yi)(yi)路(lu)径(jing)(jing)，一(yi)(yi)小(xiao)部分(fen)(fen)经(jing)(jing)定(ding)(ding)子(zi)—转(zhuan)(zhuan)子(zi)—转(zhuan)(zhuan)轴—轴承(cheng)(cheng)—机(ji)(ji)(ji)壳(qiao)(qiao)—地—变(bian)频器(qi)外壳(qiao)(qiao)这(zhei)一(yi)(yi)路(lu)径(jing)(jing)。当变(bian)频器(qi)接(jie)地与电(dian)(dian)机(ji)(ji)(ji)外壳(qiao)(qiao)间阻(zu)抗高于变(bian)频器(qi)外壳(qiao)(qiao)与负(fu)(fu)载(zai)间阻(zu)抗时还会(hui)产生轴延伸电(dian)(dian)流(liu)，经(jing)(jing)定(ding)(ding)子(zi)—机(ji)(ji)(ji)壳(qiao)(qiao)—转(zhuan)(zhuan)轴—负(fu)(fu)荷端轴承(cheng)(cheng)（电(dian)(dian)机(ji)(ji)(ji)）—联(lian)轴器(qi)—轴承(cheng)(cheng)（负(fu)(fu)载(zai)）—地—变(bian)频器(qi)外壳(qiao)(qiao)这(zhei)一(yi)(yi)回路(lu)泄(xie)放(fang)，不但危害电(dian)(dian)机(ji)(ji)(ji)负(fu)(fu)荷端轴承(cheng)(cheng)，还会(hui)危害负(fu)(fu)载(zai)轴承(cheng)(cheng)和联(lian)轴器(qi)。后两路(lu)共模(mo)电(dian)(dian)流(liu)流(liu)经(jing)(jing)电(dian)(dian)机(ji)(ji)(ji)轴承(cheng)(cheng)，造成危害并以(yi)第二(er)种途径(jing)(jing)危害更大(da)。