需要系数法确定计算负荷

1、(1)用电设备组的计算负荷及计算电流:有功功率PjsK X PN ,kW（ 5-2-5）无功功率QjsPjstg,kvar （ 5-2-6）视在功率Sjsp2jsQ2s, kVA（5-2-7）Sjs计算电流Ijs J , A (5-2-8 )V3Ur(2)配电干线或车间变电所的计算负荷：有功功率PJsK p（KxPn）, kW（5-2-9）无功功率QjsK q（KxPztg ）, kvar（5-2-10）视在功率Sjs,pj2Q2s, kVA（5-2-11）以上式中Pn 用电设备组的设备功率，kWKx 需要系数；见表 5-2-1、表5-2-2及表5-2-3 ；tg 用电设备功率因数角的正切值，

2、见表5-2-1、表5-2-3、表5-2-4及表5-2-5 ；K P、K q 有功功率、无功功率同时系数，分别取0.80.9和0.930.97 ；Ur用电设备额定电压(线电压)，kV表5-2-1用电设备的KX、cos及tg用电设备组名称单独传动的金属加工机床小批生产的金属冷加工机床0.120.160.501.73大批生产的金属冷加工机床0.170.200.501.73小批生产的金属热加工机床0.200.250.550.601.511.33大批生产的金属热加工机床0.250.280.651.17锻锤、压床、剪床及其他锻工机械00.250.601.33木工机械0.200.300.500.601.73

3、1.33液压机0.300.601.33生产用通风机0.750.850.800.850.750.62卫生用通风机0.650.700.800.75泵、活塞型压缩机、电动发电机组0.750.850.800.75球磨机、破碎机、筛选机、搅拦机等0.750.850.800.850.750.62电阻炉（带调压器或变压器）非自动装料0.600.700.950.980.330.20自动装料0.700.800.950.980.330.20干燥箱、加热器等0.400.601.000工频感应电炉（不带无功补偿装置）0.800.352.68高频感应电炉（不带无功补偿装置）0.800.601.33焊接和加热用咼频加热设

4、备0.500.650.701.02熔炼用咼频加热设备0.800.850.800.850.750.62表面淬火电炉（带无功补偿装置）电动发电机0.650.701.02真空管振荡器0.800.850.62中频电炉（中频机组）0.650.750.800.75氢气炉（带调压器或变压器）0.400.500.850.900.620.48真空炉（带调压器或变压器）0.550.650.850.900.620.48电弧炼钢炉变压器0.900.850.62电弧炼钢炉的辅助设备0.150.501.73点焊机、缝焊机0.35, 0.20 0.601.33对焊机0.350.701.02自动弧焊变压器0.500.501.

5、73单头手动弧焊变压器0.350.352.68多头手动弧焊变压器0.400.352.68单头直流弧焊机0.350.601.33多头直流弧焊机0.700.701.02金属、机修、装配车间、锅炉房用起0.100.150.51.73重机（& =25%铸造车间起重机（ =25%0.150.300.51.73联锁的连续运输机械0.650.750.88非联锁的连续运输机械0.500.600.750.88一般工业用硅整流装置0.500.701.02电镀用硅整流装置0.500.750.88电解用硅整流装置0.700.800.75红外线干燥设备0.850.901.000.00电火花加装置0.500.601.33

6、超声波装置0.700.701.02X光设备0.300.551.52电子计算机主机0.600.700.800.75电子计算机外部设备0.400.500.501.73试验设备（电热为主）0.200.400.800.75试验设备（仪表为主）0.150.200.701.02磁粉探伤机0.200.402.29铁屑加工机械0.400.750.88排气台0.500.600.900.48老炼台0.600.700.701.02陶瓷隧道窑0.800.900.950.33拉单晶炉0.700.750.900.48赋能腐蚀设备0.600.930.40真空浸渍设备0.700.950.33点焊机的需要系数0.2仅用于电子行

7、业表5-2-2照明用电设备需要系数建筑类别&建筑类别生产厂房（有天然采光）0.800.90宿舍区0.600.80生产厂房（无天然米0.901.00医院0.50光）办公楼0.700.80食堂0.900.95设计室0.900.95商店0.90科研楼0.800.90学校0.600.70仓库0.500.70展览馆0.700.80锅炉房0.90旅馆0.600.70表5-2-3旅游旅馆用电设备的Kx、cos及tg用电设备组名称Kx用电设备组名称Kx昭八、明客房0.35 0.450.950.33电梯0.180.220.501.73其他场所0.50 0.70洗衣机0.30 0.350.701.02冷水机组、泵

8、0.65 0.750.800.75厨房设备0.35 0.450.750.88通风机0.60 0.700.800.75窗式空0.35 0.450.800.75调器表5-2-4 照明用电设备的cos及tg光源类别光源类别白炽灯、卤1.000.00高压钠灯0.451.98钨灯荧光灯（无0.551.52金属卤化物0.400.612.291.29补偿）灯荧光灯（有0.900.49镝灯0.521.60补偿）高压汞灯0.450.651.981.16氙灯0.900.48表 5-2-5 cos 与 tg 、sin1.0000.0000.0000.8700.5670.4930.6501.1690.7600.990

9、0.1420.1410.8600.5930.5100.6001.3330.8000.9800.2030.1990.8500.6200.5270.5501.5180.8350.9700.2510.2430.8400.6460.5430.5001.7320.8660.9600.2920.2800.8300.6720.5580.4501.9850.8930.9500.3290.3120.8200.6980.5720.4002.2910.9160.9400.3630.3410.8100.7240.5860.3502.6760.9370.9300.3950.3670.8000.7500.6000.3003.1800.9540.9200.4260.3920.7800.8020.6260.2503.8730.9680.9100.4560.4150.7500.8820.6610.2004.8990.9800.9000.4840.4360.7200.9640.6940.1506.5910.9890.8900.5120.4560.7001.0200.7140.1009.9500.9950.8800.5400.