短路電流計算及電纜校核公式

1、一、xxxxxxx電站短路電流計算110kV上網方案 (Sj=100 MVA，Uj=Up kV；單位MW、MVA、km)1、基本參數X0= 0.400X0= 0.400L = 0.00L = 0.00XL= 0.000XL= 0.000Sb= 0.00Sb= 12.500Sb= 0.000X0= 0.400Ud= 7.000Ud= 8.000Ud= 7.500L = 0.00Xb= -Xb= 0.640Xb= -XL= 0.000Sf= 0.00Sf= 10.000Sf= 0.000Xd= 0.200Xd= 0.183Xd= 0.183Xf= -Xf= 1.464Xf= -2、阻抗變換0.00

2、00.0000.000-0.640-1.464-S1-0.0000.640-1.464-S1-0.640-1.464-6.3kVG3G16.3kV115kVT1T3G237kVT26.3kV115kVd-2115kVd-1d-137kV6.3kVd-2d-137kV6.3kVd-2d-1115kV6.3kVd-2-S1-0.640-1.464-S10.6401.464S1d1點短路時1.46410000000000.0000.744S1S4Sx3、短路電流計算成果短路電流計算成果表短路點平均 電壓 Up電源計算數據短路電流計算數據電源名稱額定容量Se 直連電抗 X計算電抗 Xjs（查表）電源額

3、定電流Ie t=0st=0.2s標幺值I*(查表)有名值I 短路容量S標幺值I*0.2有名值I0.2短路容量S0.2kVMWKAKAMVAKAMVAd-16.3110kV系統(tǒng)Sx0.7449.1641.34312.310134.312.310134.3發(fā)電機F110.001.4640.1831.1466.1277.01976.64.1004.69751.2發(fā)電機F23450.0010000000000.000.0000.0006.1270.0000.04.1000.0000.019.329210.917.007185.6d-2115110kV系統(tǒng)Sx0.1040.5029.5754.80795

4、7.44.807957.4發(fā)電機F110.002.1040.2630.0634.2900.26953.63.2530.20440.7發(fā)電機F23450.0010000000000.0000.0000.0006.1270.0000.04.1000.0000.05.0761011.15.011998.1注釋37kV6.3kVd-2d-137kV6.3kVd-2d-1d-1發(fā)電機電抗標么值：Xf=Xd%/100*Sj/Sf有名值計算：I=Ie*I* 變壓器電抗標么值：Xb=Ud%/100*Sj/Sb短路容量：S=1.732*Up*I線路電抗標么值：XL=X0*L*Sj/Up2計算電抗(從基準容量Sj

5、換算到額定容量Se的標么值)：XjsX(f、b、L)*Se/Sj額定電流：Ie=Se/(1.732*Up) 系統(tǒng)Se=SjI*計算：電源無限大時或以電源為基準的計算電抗標幺值Xjs3時，為的倒數；否則查水輪機運算曲線或運算表。開關設備校驗：額定斷流容量S；極限通過電流峰值Ich；額定開斷電流I；允熱穩(wěn)定電流2允許通過時間tI20.20.2 ； 額定關合電流ich以下是查算發(fā)電機短路電流曲線表的中間過程可不必查看！d-1短路時F1回路I*t計算I*0S= 6.127I*0.2S=4.1I*4S= 3.0810.183xjs0.35I*t=0s6.127I*t=0.2s 4.1I*t=4s3.08

6、1Xjs0.180.200.220.240.260.280.300.320.340.360.380.40t=06.1275.5265.0554.6474.2903.9933.7273.4943.2853.0952.9222.767t=0.24.1003.8563.6333.4333.2533.0962.9502.8172.6922.5742.4642.361t=43.0813.2343.1913.1513.0983.0432.9932.9432.8912.8372.7822.728d-1短路時F234回路I*t計算I*0S= 6.127I*0.2S=4.1I*4S= 3.0810.000 xj

7、s0.35I*t=0s6.127I*t=0.2s 4.1I*t=4s3.081Xjs0.180.200.220.240.260.280.300.320.340.360.380.40t=06.1275.5265.0554.6474.2903.9933.7273.4943.2853.0952.9222.767t=0.24.1003.8563.6333.4333.2533.0962.9502.8172.6922.5742.4642.361t=43.0813.2343.1913.1513.0983.0432.9932.9432.8912.8372.7822.728d-2短路時F1回路I*t計算I*0S

8、=4.29I*0.2S= 3.253I*4S= 3.0980.263xjs0.35I*t=0s4.29I*t=0.2s 3.253I*t=4s3.098Xjs0.180.200.220.240.260.280.300.320.340.360.380.40t=06.1275.5265.0554.6474.2903.9933.7273.4943.2853.0952.9222.767t=0.24.1003.8563.6333.4333.2533.0962.9502.8172.6922.5742.4642.361t=43.0813.2343.1913.1513.0983.0432.9932.9432.

9、8912.8372.7822.728d-2短路時F234回路I*t計算I*0S= 6.127I*0.2S=4.1I*4S= 3.0810.000 xjs0.35I*t=0s6.127I*t=0.2s 4.1I*t=4s3.081Xjs0.180.200.220.240.260.280.300.320.340.360.380.40t=06.1275.5265.0554.6474.2903.9933.7273.4943.2853.0952.9222.767t=0.24.1003.8563.6333.4333.2533.0962.9502.8172.6922.5742.4642.361t=43.08

10、13.2343.1913.1513.0983.0432.9932.9432.8912.8372.7822.728水輪發(fā)電機短路電流（I*t）運算曲線Xjs0.180.200.220.240.260.280.300.320.340.360.380.40t=06.1275.5265.0554.6474.2903.9933.7273.4943.2853.0952.9222.767t=0.24.1003.8563.6333.4333.2533.0962.9502.8172.6922.5742.4642.361t=43.0813.2343.1913.1513.0983.0432.9932.9432.89

11、12.8372.7822.728Xjs0.540.560.600.650.700.750.800.850.900.951.001.05t=02.0131.9381.8021.6581.5341.4281.3361.2541.1821.1181.0611.009t=0.21.8261.7961.6651.5501.4511.3631.2861.2171.1551.0991.0481.002t=42.3962.3552.2632.1371.9641.7941.6421.5311.4031.3081.2251.152Xjs1.401.451.501.551.601.651.701.751.801.8

12、51.901.95t=00.7510.7250.7000.6770.6550.6350.6160.5980.5810.5650.5500.536t=0.20.7660.7400.7170.6940.6730.6530.6340.6160.5990.5820.5660.551t=40.8130.7800.7500.7220.6960.6720.6490.6280.6090.5900.5720.556Xjs2.302.352.402.452.502.552.602.652.702.752.802.85t=00.4530.4430.4340.4250.4160.4080.4000.3920.3850

13、.3780.3710.364t=0.20.4620.4520.4410.4310.4220.4130.4040.3960.3880.3800.3730.366t=40.4620.4520.4410.4310.4220.4130.4040.3960.3880.3800.3730.366現在是 2005/1/25 14:07X0= 0.400L = 18.00XL= 0.054Sb= 8.00Ud= 7.500Xb= 0.938系統(tǒng)電抗標幺值 Xx 0.050已知與該系統(tǒng)連接的Sf= 0.00 斷路器的斷流容量 Sdn 2000.0Xd= 0.200Xf= -S0.0540.9380.050-S4

14、Sx-0.104S4Sx-0.104Sx115kVG46.3kVT4電站短路電流計算110kV上網方案 (Sj=100 MVA，Uj=Up kV；單位MW、MVA、km)115kVS4Sx-0.104S4Sx-0.104S4Sxd2點短路時2.10410000000000.0000.104S1S4Sx短路電流熱效應 Qzt (KA2*t)t=4s沖擊系數Kch沖擊短路電流ich短路全電流最大有效值 Ich標幺值I*4有名值I4短路容量S40.2 s2.5 sKAMVAKAKA周期分量非周期分量周期分量非周期分量12.310134.31.9033.0819.933.0813.52938.518.

15、8611.363.0810.0000.00.000.0015.840172.851.9431.2966.2874.72141.01774.2974.72849.014.807957.41.8512.587.523.0980.19438.70.700.423.0810.0000.00.000.005.001996.213.287.945.09 2.837.9263.472.8366.31d-2短路電流計算成果表短路電流計算數據小插件 Y-變換計算X31=7.612X1=0.175X21=1.592X2=1.380X32=60.03X3=6.600X1=0.175X31=7.612X2=1.380

16、X21=1.592X3=6.600X32=60.030.35=xjs0.53I*t=0s3.0950.53=xjs0.925I*t=0sI*t=0.2s 2.574I*t=0.2sI*t=4s2.837I*t=4s0.420.440.460.480.500.520.54 0.560.600.650.700.750.800.852.6272.5002.3852.2802.1832.0952.0131.9381.8021.6581.5341.4281.3361.2542.2672.1792.0982.0231.9531.8871.8261.7961.6651.5501.4511.3631.2861

17、.2172.6752.6242.5752.5272.4822.4382.3962.3552.2632.1371.9641.7941.6421.5310.35=xjs0.53I*t=0s3.0950.53=xjs0.925I*t=0sI*t=0.2s 2.574I*t=0.2sI*t=4s2.837I*t=4s0.420.440.460.480.500.520.54 0.560.600.650.700.750.800.852.6272.5002.3852.2802.1832.0952.0131.9381.8021.6581.5341.4281.3361.2542.2672.1792.0982.0

18、231.9531.8871.8261.7961.6651.5501.4511.3631.2861.2172.6752.6242.5752.5272.4822.4382.3962.3552.2632.1371.9641.7941.6421.5310.35=xjs0.53I*t=0s3.0950.53=xjsS；極限通過電流峰值Ich；額定開斷電流I；允熱穩(wěn)定電流2允許通過時間tI20.20.2 ； 額定關合電流ich以下是查算發(fā)電機短路電流曲線表的中間過程可不必查看！0.35=xjs0.53I*t=0s3.0950.53=xjs0.925I*t=0sI*t=0.2s 2.574I*t=0.2sI

19、*t=4s2.837I*t=4s0.420.440.460.480.500.520.54 0.560.600.650.700.750.800.852.6272.5002.3852.2802.1832.0952.0131.9381.8021.6581.5341.4281.3361.2542.2672.1792.0982.0231.9531.8871.8261.7961.6651.5501.4511.3631.2861.2172.6752.6242.5752.5272.4822.4382.3962.3552.2632.1371.9641.7941.6421.5310.420.440.460.480

20、.500.522.6272.5002.3852.2802.1832.0952.2672.1792.0982.0231.9531.8872.6752.6242.5752.5272.4822.4381.101.151.201.251.301.350.9620.9190.8800.8430.8100.7800.9590.9200.8850.8520.8210.7921.0871.0290.9770.9300.8880.8492.002.052.102.152.202.250.5220.5090.4970.4850.4740.4630.5370.5230.5100.4970.4850.4730.540

21、0.5250.5120.4980.4860.4742.902.953.003.053.103.150.3580.3510.3450.3390.3340.3280.3590.3530.3460.3400.3340.3290.3590.3530.3460.3400.3340.329水輪發(fā)電機短路電流（I*t）運算曲線2.0130.925=xjs1.375I*t=0s1.1181.826I*t=0.2s 1.0992.396I*t=4s1.3080.900.951.001.051.101.151.201.251.301.351.401.451.501.551.1821.1181.0611.0090.

22、9620.9190.8800.8430.8100.7800.7510.7250.7000.6771.1551.0991.0481.0020.9590.9200.8850.8520.8210.7920.7660.7400.7170.6941.4031.3081.2251.1521.0871.0290.9770.9300.8880.8490.8130.7800.7500.7222.0130.925=xjs1.375I*t=0s1.1181.826I*t=0.2s 1.0992.396I*t=4s1.3080.900.951.001.051.101.151.201.251.301.351.401.4

23、51.501.551.1821.1181.0611.0090.9620.9190.8800.8430.8100.7800.7510.7250.7000.6771.1551.0991.0481.0020.9590.9200.8850.8520.8210.7920.7660.7400.7170.6941.4031.3081.2251.1521.0871.0290.9770.9300.8880.8490.8130.7800.7500.7222.0130.925=xjs1.375I*t=0s1.1181.826I*t=0.2s 1.0992.396I*t=4s1.3080.900.951.001.05

24、1.101.151.201.251.301.351.401.451.501.551.1821.1181.0611.0090.9620.9190.8800.8430.8100.7800.7510.7250.7000.6771.1551.0991.0481.0020.9590.9200.8850.8520.8210.7920.7660.7400.7170.6941.4031.3081.2251.1521.0871.0290.9770.9300.8880.8490.8130.7800.7500.7222.0130.925=xjs1.375I*t=0s1.1181.826I*t=0.2s 1.0992

25、.396I*t=4s1.3080.900.951.001.051.101.151.201.251.301.351.401.451.501.551.1821.1181.0611.0090.9620.9190.8800.8430.8100.7800.7510.7250.7000.6771.1551.0991.0481.0020.9590.9200.8850.8520.8210.7920.7660.7400.7170.6941.4031.3081.2251.1521.0871.0290.9770.9300.8880.8490.8130.7800.7500.7221.375=xjs1.825I*t=0

26、s0.7511.825=xjs2.275I*t=0s0.565I*t=0.2s 0.766I*t=0.2s 0.582I*t=4s0.813I*t=4s0.591.601.651.701.751.801.851.901.952.002.052.102.152.202.250.6550.6350.6160.5980.5810.5650.5500.5360.5220.5090.4970.4850.4740.4630.6730.6530.6340.6160.5990.5820.5660.5510.5370.5230.5100.4970.4850.4730.6960.6720.6490.6280.60

27、90.5900.5720.5560.5400.5250.5120.4980.4860.4741.375=xjs1.825I*t=0s0.7511.825=xjs2.275I*t=0s0.565I*t=0.2s 0.766I*t=0.2s 0.582I*t=4s0.813I*t=4s0.591.601.651.701.751.801.851.901.952.002.052.102.152.202.250.6550.6350.6160.5980.5810.5650.5500.5360.5220.5090.4970.4850.4740.4630.6730.6530.6340.6160.5990.58

28、20.5660.5510.5370.5230.5100.4970.4850.4730.6960.6720.6490.6280.6090.5900.5720.5560.5400.5250.5120.4980.4860.4741.375=xjs1.825I*t=0s0.7511.825=xjs2.275I*t=0s0.565I*t=0.2s 0.766I*t=0.2s 0.582I*t=4s0.813I*t=4s0.591.601.651.701.751.801.851.901.952.002.052.102.152.202.250.6550.6350.6160.5980.5810.5650.55

29、00.5360.5220.5090.4970.4850.4740.4630.6730.6530.6340.6160.5990.5820.5660.5510.5370.5230.5100.4970.4850.4730.6960.6720.6490.6280.6090.5900.5720.5560.5400.5250.5120.4980.4860.4741.375=xjs1.825I*t=0s0.7511.825=xjs2.275I*t=0s0.565I*t=0.2s 0.766I*t=0.2s 0.582I*t=4s0.813I*t=4s0.591.601.651.701.751.801.851

30、.901.952.002.052.102.152.202.250.6550.6350.6160.5980.5810.5650.5500.5360.5220.5090.4970.4850.4740.4630.6730.6530.6340.6160.5990.5820.5660.5510.5370.5230.5100.4970.4850.4730.6960.6720.6490.6280.6090.5900.5720.5560.5400.5250.5120.4980.4860.4742.275=xjs2.725I*t=0s0.453I*t=0.2s 0.462I*t=4s0.4622.302.352

31、.402.452.502.552.602.652.702.752.802.852.902.950.4530.4430.4340.4250.4160.4080.4000.3920.3850.3780.3710.3640.3580.3510.4620.4520.4410.4310.4220.4130.4040.3960.3880.3800.3730.3660.3590.3530.4620.4520.4410.4310.4220.4130.4040.3960.3880.3800.3730.3660.3590.3532.275=xjs2.725I*t=0s0.453I*t=0.2s 0.462I*t=

32、4s0.4622.302.352.402.452.502.552.602.652.702.752.802.852.902.950.4530.4430.4340.4250.4160.4080.4000.3920.3850.3780.3710.3640.3580.3510.4620.4520.4410.4310.4220.4130.4040.3960.3880.3800.3730.3660.3590.3530.4620.4520.4410.4310.4220.4130.4040.3960.3880.3800.3730.3660.3590.3532.275=xjs2.725I*t=0s0.453I*

33、t=0.2s 0.462I*t=4s0.4622.302.352.402.452.502.552.602.652.702.752.802.852.902.950.4530.4430.4340.4250.4160.4080.4000.3920.3850.3780.3710.3640.3580.3510.4620.4520.4410.4310.4220.4130.4040.3960.3880.3800.3730.3660.3590.3530.4620.4520.4410.4310.4220.4130.4040.3960.3880.3800.3730.3660.3590.3532.275=xjs2.

34、725I*t=0s0.453I*t=0.2s 0.462I*t=4s0.4622.302.352.402.452.502.552.602.652.702.752.802.852.902.950.4530.4430.4340.4250.4160.4080.4000.3920.3850.3780.3710.3640.3580.3510.4620.4520.4410.4310.4220.4130.4040.3960.3880.3800.3730.3660.3590.3530.4620.4520.4410.4310.4220.4130.4040.3960.3880.3800.3730.3660.359

35、0.3532.725=xjs3.155I*t=0s0.378I*t=0.2s 0.38I*t=4s0.383.003.053.103.150.3450.3390.3340.3280.3460.3400.3340.3290.3460.3400.3340.3292.725=xjs3.155I*t=0s0.378I*t=0.2s 0.38I*t=4s0.383.003.053.103.150.3450.3390.3340.3280.3460.3400.3340.3290.3460.3400.3340.3292.725=xjs3.155I*t=0s0.378I*t=0.2s 0.38I*t=4s0.3

36、83.003.053.103.150.3450.3390.3340.3280.3460.3400.3340.3290.3460.3400.3340.3292.725=xjs3.155I*t=0s0.378I*t=0.2s 0.38I*t=4s0.383.003.053.103.150.3450.3390.3340.3280.3460.3400.3340.3290.3460.3400.3340.3296-35kV 電力電纜選擇pass.交聯聚乙希絕緣聚氯乙希護套3芯電力電纜允許載流量Ixu（A）纜芯最高溫度90度一、電壓選擇纜芯截面mm2空氣中敷設（環(huán)境溫度40度）1-3kV6kV10kV20-

37、35kV回路最高工作電壓 Ugmax6.30kV無鋼鎧 有鋼鎧 無鋼鎧 有鋼鎧 環(huán)境溫度25度電力電纜額定電壓Un6.00kV2591*10010085Ugmax=1.15Un滿足要求35114114*12312311050146141*146141135二、截面選擇70178173*17817316595214209*2192141802、按工作電流選擇120246246*251246200150278277*283278230回路額定功率Pn 1600kW185319323*324320*回路額定工作電壓Un 6.30kV240378378*378373*回路持續(xù)工作電流Ig 192A30

38、0419432*433428*選用交聯聚乙希絕緣YJLV-3 70mm2400*505*506501*聚氯乙希護套電纜500*584*579574*允許載流量Ixu 173(銅芯則*1.29)表中系鋁芯電纜數值，銅芯電纜可乘以1.29系數不同環(huán)境溫度時校正系數Khj 1.00參見電力工程電纜設計規(guī)范GB50217-94；水-機電-手冊電一P318空氣中多根并行敷設時K1 0.90在空氣中或穿管敷設時K2 0.8535kV及以下電纜在不同環(huán)境溫度時的載流量校正系數KhjKhj*K1*K2*Ixu 1325000小時，長度20m時，則按經濟電流密度選擇701.151.081.000.911.051

39、.00801.111.061.000.931.041.00所選截面 S=70小于86mm2不合要求901.091.051.000.941.041.00（Tmax=3000-5000小時，j銅=2.25，j鋁=1.73）交聯聚乙希絕緣聚氯乙希護套電力電纜電壓損失系數Ku/A*km4、按電壓損失校驗截面截面mm23*163*253*350.4kV 銅芯、cos=0.8、=60度0.4860.3110.222電壓損失系數Ku= 0.006/A*km6 kV 銅芯、cos=0.8、=80度0.0350.0230.017電纜長度L= 30m 10kV 銅芯、cos=0.8、=80度0.0210.0140

40、.010電壓損失u= 0.03 5.0%參見小型水電站機電設計手冊電一P279；水電站機電設計手冊電一P315滿足要求5、按熱穩(wěn)定校驗截面為了保證電纜末端發(fā)生短路時，電纜芯線溫度不超過允許值，電纜允許熱效應t應不小于線路計算的短路電流熱效應dt值（對于長度200m的高壓電纜可按短路發(fā)生在首端計算）。計算短路電流可按三相短路計算，并考慮系統(tǒng)5-10年的發(fā)展。電纜的允許熱效應Qt(CS)2 65kA2 *s小于92不合要求（短路電流熱效應，見短路電流計算表）熱穩(wěn)定系數C （1/）*JQ/（kj*20*）ln(1+（d-20）)/(1+（g-20）)0.5*10-2115.035kV及以下電纜芯在短路前的實際運行最高溫度g 0(c0)(Ig/Ixu)2 102度芯線溫度變化及絕緣影響系數 0.93（3-6kV取0.93；35kV以上取1.0）纜芯