电缆载流量计算书示例.docx

1、电缆载流量计算书示例电缆载流量计算书（示例）欢迎下载一、基本条件1、电缆结构名称所在层材料内径(mm)厚度(mm)外径(mm)截面积(mm)导体导体铜0.00.023.8368.0导体屏蔽绝缘半导电材料23.80.825.461.8绝缘绝缘交联聚乙烯25.40.626.649.0绝缘屏蔽绝缘半导电材料26.64.535.6102.0内护(导体)内护层铜带35.60.236.022.5内护(非金属)内护层聚氯乙烯护套36.00.236.422.7铠装外护层钢带铠装36.40.036.40.0外护外护层聚氯乙烯护套36.42.341.0112.62、运行状况电流类型：三相交流电压等级：35kV电缆

2、数量：3中心点坐标(mm)：X = 500.00, Y = 500.00回路间距(mm)：100.00电缆间距(mm)：100.003、电缆敷设方式、环境条件和运行状况敷设条件：空中干燥和潮湿土壤热阻系数之比率：1.0干燥土壤的热阻系数：1.0自然土壤的热阻系数：1.0土壤临界温度()：40.0 环境温度()：40.0 土壤临界温升()：40.0 二、载流量计算1、交流电阻(1)导体最高工作温度下单位长度直流电阻已知:R0 = 0.000047 /m 20 = 0.003930 1/k = 90.0 结果:R = 0.000060 /m(2)集肤效应因数已知:f = 50 Hz R = 0.0

3、00060 /m ks = 1.000结果:xs2 = 2.096852结果:ys = 0.022488(3)邻近效应因数已知:f = 50 Hz R = 0.000060 /m kp = 0.80结果:xp2 = 1.677482 不等距时 已知:dc = 23.8 mm s = 100.0 mm结果:yp = 0.003418(4)交流电阻已知:R = 0.000060 /m ys = 0.022488 yp = 0.003418结果:R = 0.000061 /m2、绝缘损耗(1)导体电容已知: = 2.5 Di = 26.6 mm dc = 23.8 mm结果:c = 1.249e-0

4、09 F/m(2)绝缘损耗 已知: = 314.2 rad/s c = 1.249e-009 F/m U0 = 20207.26 V tg = 0.004结果:Wd = 0.640748 W/m3、金属套或屏蔽中的功率损耗(1)最高工作温度下电缆单位长度金属套或屏蔽的电阻已知:s = 1.724e-008 m As = 0.000022 m2 s = 0.003930 1/K = 90.0 = 0.90结果:Rs = 0.000950 /m(2)1已知: = 314.159265rad/s s = 1.724100e-008 m结果:1 = 151.320805(3)gs已知:ts = 0.2

5、mm Ds = 36.0mm 1 = 151.320805结果:gs = 1.000458(4)m已知: = 314.159265rad/s Rs = 0.000950/m结果:m = 0.033071(5)滞后相涡流损耗0、1、2 已知:m = 0.033071 d = 35.8mm s = 100.0mm结果:0 = 0.000053 1 = 0.022337 2 = 0.000000涡流损耗结果:1 = 0.000831(6)中间电缆涡流损耗0、1、2 已知:m = 0.033071 d = 35.8mm s = 100.0mm结果:0 = 0.000210 1 = 0.000007 2

6、 = 0.000000涡流损耗结果:1 = 0.003248(7)越前相涡流损耗0、1、2 已知:m = 0.033071 d = 35.8mm s = 100.0mm结果:0 = 0.000053 1 = 0.013723 2 = 0.000000涡流损耗结果:1 = 0.000824(9)金属套或屏蔽环流损耗结果:1 = 0(10)金属套或屏蔽功率损耗 结果:三相中最大的1 = 0.0032484、铠装损耗因数已知:无铠装结果:2 = 05、电缆绝缘热阻T1已知:T = 3.5 Km/W t1 = 5.9 mm dc = 23.8 mm结果:T1 = 0.224299 Km/W6、金属套和

7、铠装之间热阻T2已知:T = 6.0 Km/W t2 = 0.2 mm Ds = 36.0 mm结果:T2 = 0.010552 Km/W7、外护层热阻T3已知:T = 6.0 Km/W t3 = 2.3 mm Da = 36.4 mm结果:T3 = 0.113640 Km/W8、电缆外部热阻T4(1)散热系数h已知:Z = 0.62 E = 1.95 g = 0.25 De = 0.0410 m结果:h = 3.328(2)d已知:Wd = 0.640748 W/m 1 = 0.003248 2 = 0.000000 T1 = 0.224299 KW/m T2 = 0.010552 KW/m

8、 n = 1结果:d = 0.071394 K(3)KA已知:T1 = 0.224299 KW/m T2 = 0.010552 KW/m T3 = 0.113640 KW/m 1 = 0.003248 2 = 0.000000 n = 1 De = 0.0410 m结果:KA = 0.149066(4)超过环境温度以上的电缆表面温升s已知: = 50.0 K d = 0.071394 K KA = 0.149066 s0.25初值 = 2.0结果:s0.25 = 2.460223 K(5)T4结果:T4 = 0.948267 KW/m9电缆额定载流量I已知:交流电阻R = 0.000061 /

9、m金属屏蔽损耗1 = 0.003248铠装损耗2 = 0.000000介质损耗Wd = 0.640748 W/m热阻T1 = 0.224299 Km/W热阻T2 = 0.010552 Km/W热阻T3 = 0.113640 Km/W热阻T4 = 0.948267 Km/W结果:I = 784.831854 A护套感应电压计算书1.计算护套感应电压的中间参数Xs已知:f = 50.000000 Hz Ds = 36.000000 mm S = 100.000000 mm结果:Xs = 0.000108 /m2.计算护套感应电压的中间参数Xm已知:f = 50.000000 Hz结果:Xm = 0

10、.000044 /m3.电缆护套感应电压U已知:I = 784.831854 A Xs = 0.000108 /m Xm = 0.000044 /m结果:U = 0.105874 /m电缆绝缘厚度计算书1.计算电缆绝缘厚度的中间参数老化系数已知:t = 30.000000 年 n = 9.000000结果:K2 = 4.0011112.(按AC)计算电缆绝缘厚度已知:Eo = 20.207259 kV K1 = 1.100000 K2 = 4.001111 K3 = 1.100000 Elac = 30.000000 kV/mm结果:Tac = 3.261000 mm3.(按冲击电压)计算电缆

11、绝缘厚度已知:BIL = 550.000000 kV I1 = 1.250000 I2 = 1.100000 I3 = 1.100000 EIimp = 60.000000 kV/mm结果:Timp = 13.865000 mm4.(最终结果)计算电缆绝缘厚度已知:Tac = 3.261000 mm Timp = 13.865000 mm结果:Timp = 14.900000 mm电缆导体短路电流计算书1.计算电缆导体短路电流中间参数(K)载流体常数已知:c = 3450000.000000 J/K.m3 = 254.452926 20 = 0.000000 .m结果:K = 741.0751

12、56 As1/2/mm22.计算电缆导体短路电流已知:K = 741.075156 As1/2/mm2 S = 368.000000 mm2 t = 3.000000 秒f = 250.000000 i = 90.000000 = 254.452926结果:I = 97.300000 KA/3S电缆金属屏蔽短路电流计算书1.计算电缆金属屏蔽短路电流中间参数(K)载流体常数已知: = 2500000.000000 J/K.m3 = 254.452926 = 0.000000结果:K = 630.8450672.计算电缆金属屏蔽短路电流已知:K = 630.845067 As1/2/mm2 S =

13、 368.000000 mm2 t = 3.000000 秒 f = 200.000000 i = 90.000000 = 254.452926 = 1.200000 结果:I = 84.700000 KA/3S电缆使用过程中电动力计算书1.电缆使用过程中电动力最大值已知:S = 1.000000 mm lm = 97300.000000 A/1S cost - 31/2cost = 31/2(最大值)结果:F = 1420.093500 N/m2.电缆使用过程中电动力最小值已知:S = 1.000000 mm lm = 97300.000000 A/1S cost - 31/2cost =

14、31/2/2(最小值)结果:F = 710.046750 N/m电缆工井长度计算书1、电缆温升后电缆伸长量(1)临界温度t计算已知:A = 368.000000 mm2 E = 30000.000000 N/mm2 = 0.000020 l/ = 0.300000W = 161.300000 N/m L = 150.000000 m f = 1000.000000 N结果:t = 41.930000 (2)按电缆弯曲半径要求计算温升65时已知:t = 65 A = 368.000000 mm2 E = 30000.000000 N/mm2 = 0.000020 l/ = 0.300000W =

15、 161.300000 N/m L = 150.000000 m f = 1000.000000 N结果:m = 0.060000 m(3)按电缆弯曲半径要求计算温升25时已知:t = 25 A = 368.000000 mm2 E = 30000.000000 N/mm2 = 0.000020 l/ = 0.300000W = 161.300000 N/m L = 150.000000 m f = 1000.000000 N结果:m = 0.000000 m2、工井内电缆弯曲段长度S计算(1)220KV单芯XLPE电缆允许最小施工弯曲半径R0已知:D = 0.041000 m结果:R0 =

16、0.820000 m(2)电缆工井试算长度S已知:R0 = 0.820000 m C = 0.500000 m结果:R0 = 1.200000 m(3)修正施工弯曲半径R0已知:S = 1.200000 m C = 0.500000 m结果:R0 = 0.850000 m(4)修正相邻工井间电缆距离La已知:S = 1.200000 m C = 0.500000 m结果:La = 1.300000 m(5)修正计算过程中间变量0已知:S = 1.200000 m C = 0.500000 m结果:0 = 0.789582(6)修正计算过程中间变量B0已知:R0 = 0.850000 m 0 =

17、 0.789582结果:B0 = 0.065370 m(7)修正计算过程中间变量B1已知:m = 0.060000 m B0 = 0.065370 m La = 1.300000 m结果:B1 = 0.110300 m(8)验证S是否合理的阶段性结果R1已知:B1 = 0.110300 m La = 1.300000 m结果:R1 = 0.533958 m(9)S本次试算时的取值已知:S = 1.200000 m结果:S = 1.200000 m(10)S下次试算时的取值(可能不采用)已知:S = 1.200000 m Step = 0.3 m结果:S = 1.500000 m(11)修正施工

18、弯曲半径R0已知:S = 1.500000 m C = 0.500000 m结果:R0 = 1.250000 m(12)修正相邻工井间电缆距离La已知:S = 1.500000 m C = 0.500000 m结果:La = 1.581000 m(13)修正计算过程中间变量0已知:S = 1.500000 m C = 0.500000 m结果:0 = 0.643501(14)修正计算过程中间变量B0已知:R0 = 1.250000 m 0 = 0.643501结果:B0 = 0.064130 m(15)修正计算过程中间变量B1已知:m = 0.060000 m B0 = 0.064130 m

19、La = 1.581000 m结果:B1 = 0.117100 m(16)验证S是否合理的阶段性结果R1已知:B1 = 0.117100 m La = 1.581000 m结果:R1 = 0.725598 m(17)S本次试算时的取值已知:S = 1.500000 m结果:S = 1.500000 m(18)S下次试算时的取值(可能不采用)已知:S = 1.500000 m Step = 0.3 m结果:S = 1.800000 m(19)按电缆弯曲半径要求试算的结果S已知:S = 1.500000 m结果:S = 1.500000 m按保护层疲劳限制核算畸变量并根据结果再次试算S(20)按保

20、护层疲劳限制核算畸变量已知:S = 1.500000 m C = 0.500000 m d = 0.035800 m m = 0.000000 m结果: = 0.000000 m(21)S本次试算时的取值已知:S = 1.500000 m结果:S = 1.500000 m(22)S下次试算时的取值(可能不采用)已知:S = 1.500000 m Step = 0.3 m结果:S = 1.800000 m(23)按保护层疲劳限制试算的结果S已知:S = 1.500000 m结果:S = 1.500000 m3、工井长度已知:S = 1.500000 m 电缆接头长 = 2.000000 m结果:工井长度 = 5.600000 m