1、 电电动动机机启启动动计计算算 系统容量视为无穷大，变压器为630KVA油浸变压器，上级母线距车间母线采用2根185电缆连接（150米），电动机距车间母线50米。系系统统示示意意图图1-1一一、计计算算数数据据1、电动机频繁启动(1)选用电机为75KW三相鼠笼异步电机主要电气参数SSrTxTSkm Qfh SfhXlSqMSq10.05518.180.4800.8000.0340.6450.561IrMUrMkqSuqmuqM0.1400.38071500.9710.844(2)选用电机为55KW三相鼠笼异步电机主要电气参数SSrTxTSkm Qfh SfhXlSqMSq0.630.04514
2、.000.3020.5040.0130.4700.450IrMUrMkqSuqmuqM0.1020.38071500.9690.932、电动机不频繁启动(1)选用电机为132KW三相鼠笼异步电机主要电气参数SSrTxTSkm Qfh SfhXlSqMSq0.630.04514.000.3020.5040.0131.1291.022IrMUrMkqSuqmuqM0.2450.38071500.9330.84(2)选用电机为110KW三相鼠笼异步电机主要电气参数SSrTxTSkm Qfh SfhXlSqMSq0.630.04514.000.3020.5040.0140.9400.862IrMUrM
3、kqSuqmuqM0.2040.38071200.9430.86二二、计计算算过过程程1、电动机不频繁启动 Skm=SrT/(xT+SrT/S)=14(MVA)(1)选用电机为75KW三相鼠笼异步电机(SqM=0.645 MVA)。Xl=(0.07+6.3/185)*0.5*0.15+(0.07+6.3/70)*0.05=0.031+0.008=0.039Sq=1/(1/SqM+Xl/U2m)=0.549 Qfh=0.3020 uqm=(Skm+Qfh)/(Skm+Qfh+Sq)=14.302/14.851=0.963uqM=0.963*Sq/SqM=0.963*0.549/0.645=0.8
4、2(2)选用电机为55KW三相鼠笼异步电机(SqM=0.470MVA)。Xl=(0.07+6.3/185)*0.5*0.15+(0.07+6.3/50)*0.05=0.031+0.010=0.041Sq=1/(1/SqM+Xl/U2m)=0.295 Qfh=0.302 uqm=(Skm+Qfh)/(Skm+Qfh+Sq)=14.302/14.718=0.972uqM=0.972*Sq/SqM=0.972*0.416/0.472=0.86故电机功率为55KW三相鼠笼异步电机可直接启动。2、电动机频繁启动 Skm=SrT/(xT+SrT/S)=14(MVA)(1)选用电机为37KW三相鼠笼异步电机
5、(SqM=0.322 MVA)。Xl=(0.07+6.3/185)*0.5*0.15+(0.07+6.3/25)*0.05=0.031+0.016=0.047Sq=1/(1/SqM+Xl/U2m)=0.292 Qfh=0.302 uqm=(Skm+Qfh)/(Skm+Qfh+Sq)=14.302/14.594=0.980uqM=0.98*Sq/SqM=0.98*0.292/0.322=0.89(2)选用电机为30KW三相鼠笼异步电机(SqM=0.263 MVA)。Xl=(0.07+6.3/185)*0.5*0.15+(0.07+6.3/16)*0.05=0.031+0.023=0.054 Qf
6、h=0.302Sq=1/(1/SqM+Xl/U2m)=0.239 uqm=(Skm+Qfh)/(Skm+Qfh+Sq)=14.302/14.541=0.984uqM=0.984*Sq/SqM=0.984*0.239/0.263=0.90 故电机功率为30KW三相鼠笼异步电机可直接启动。工厂配电设计手册150页表6-16，钢铁手册下册193页表23-4 电电动动机机启启动动计计算算 系统容量视为无穷大，变压器为630KVA油浸变压器，上级母线距车间母线采用2根185电缆连接（150米），电动机距车间母线50米。一、电动机不频繁启动(1)选用电机为75KW三相鼠笼异步电机主要电气参数SSrTxTS
7、km Qfh SfhXlSqMSq0.630.04514.000.3020.5040.0390.6450.549IrMUrMkqSuqmuqM0.1400.3807700.9630.82(2)选用电机为55KW三相鼠笼异步电机主要电气参数SSrTxTSkm Qfh SfhXlSqMSq0.630.04514.000.3020.5040.0410.4700.415IrMUrMkqSuqmuqM0.1020.3807500.9720.86二、电动机频繁启动(1)选用电机为37KW三相鼠笼异步电机主要电气参数SSrTxTSkm Qfh SfhXlSqMSq0.630.04514.000.3020.5
8、040.0470.3220.292IrMUrMkqSuqmuqM0.0700.3807250.9800.89(2)选用电机为30KW三相鼠笼异步电机主要电气参数SSrTxTSkm Qfh SfhXlSqMSq0.630.04514.000.3020.5040.0540.3220.288IrMUrMkqSuqmuqM0.0700.3807160.9800.87一、电动机不频繁启动 Skm=SrT/(xT+SrT/S)=14(MVA)(1)选用电机为75KW三相鼠笼异步电机(SqM=0.645 MVA)。Xl=(0.07+6.3/185)*2*0.15+(0.07+6.3/70)*0.05=0.0
9、31+0.008=0.039Sq=1/(1/SqM+Xl/U2m)=0.549 Qfh=0.302 uqm=(Skm+Qfh)/(Skm+Qfh+Sq)=14.302/14.851=0.963uqM=0.963*Sq/SqM=0.963*0.549/0.645=0.82(2)选用电机为55KW三相鼠笼异步电机(SqM=0.470MVA)。Xl=(0.07+6.3/185)*2*0.15+(0.07+6.3/50)*0.05=0.031+0.010=0.041Sq=1/(1/SqM+Xl/U2m)=0.295 Qfh=0.302 uqm=(Skm+Qfh)/(Skm+Qfh+Sq)=14.302
10、/14.718=0.972uqM=0.972*Sq/SqM=0.972*0.416/0.472=0.86故电机功率为55KW三相鼠笼异步电机可直接启动。二、电动机频繁启动 Skm=SrT/(xT+SrT/S)=14(MVA)(1)选用电机为30KW三相鼠笼异步电机(SqM=0.262 MVA)。Xl=(0.07+6.3/185)*2*0.15+(0.07+6.3/16)*0.05=0.031+0.023=0.054Sq=1/(1/SqM+Xl/U2m)=0.288 Qfh=0.302 uqm=(Skm+Qfh)/(Skm+Qfh+Sq)=14.302/14.541=0.984uqM=0.983*Sq/SqM=0.983*0.2386/0.262=0.90(2)选用电机为30KW三相鼠笼异步电机(SqM=0.322 MVA)。Xl=(0.07+6.3/185)*2*0.15+(0.07+6.3/25)*0.05=0.031+0.016=0.047 Qfh=0.302Sq=1/(1/SqM+Xl/U2m)=0.292 uqm=(Skm+Qfh)/(Skm+Qfh+Sq)=14.302/14.597=0.980uqM=0.980*Sq/SqM=0.980*0.307/0.322=0.89 故电机功率为30KW三相鼠笼异步电机可直接启动。
