中央变电所低压短路电流计算
中央变电所低压配电继电保护整定计算
一、各元件阻抗计算
1、高压部分各元件折算电抗计算
系统折算电抗:
由公式X 2
xy =V ar ,2/S br 得
X =V 2
xy ar ,2/S br =(0.69kV )²/378MVA=0.0013Ω
MYPTJ8.7/10 3×50+3×25-50m 高压电缆折算电抗
X '
1=x 0L 1(V ar , 2/V 2
w ar , 1)
=0.081×0.05×(0.69/10.5)²
=0.0000175Ω
R ' 2
w 1=R 0L 1(V ar , 2/V ar , 1)
=0.448×0.05×(0.69/10.5)²
≈0.0000967Ω
变压器阻抗:
Z 2
T =v s V ar , 2/S T
=0.0408×(0.69kV )²/0.315MVA
≈0.0617Ω
R 22
T =∆P N , T V ar , 2/S T
=2500W×(0.69kV/315kVA)²
≈0.012Ω
X Z 22
T =T -R T =0. 06172-0. 0122
≈0.06Ω
2、低压电源总控K101负荷电缆(MYP-0.38/0.66 3*120-100m)阻抗 R 101=R0L 101=0.164×0.1=0.0164Ω
X 101=X0L 101=0.056×0.1=0.0056Ω
3、K103负荷-永久避难硐室电缆(MYP-0.38/0.66 3*25-360m)阻抗 R 103=R0L 103=0.864×0.36=0.31104Ω
X 103=X0L 103=0.088×0.36=0.03168Ω
4、K105负荷-井底车场调度绞车(MYP-0.38/0.66 3*16-150m)阻抗 R 105=R0L 105=1.37×0.15=0.2055Ω
X 105=X0L 105=0.09×0.15=0.0135Ω
5、K107负荷-集轨无极绳电源(MYP-0.38/0.66 3*50-200m)阻抗 R 107=R0L 107=0.448×0.2=0.0896Ω
X 107=X0L 107=0.081×0.2=0.0162Ω
6、K109负荷-泵房低压电源电缆(MYP-0.38/0.66 3*16-50m)阻抗 R 109=R0L 109=1.37×0.05=0.0685Ω
X 109=X0L 109=0.09×0.05=0.0045Ω
7、K111负荷-照明综保电源电缆(MYP-0.38/0.66 3*16-10m)阻抗 R 111=R0L 111=1.37×0.01=0.0137Ω
X 111=X0L 111=0.09×0.01=0.0009Ω
8、K113负荷-主井照明电源电缆(MYP-0.38/0.66 3*25-130m)阻抗 R 113=R0L 113=0.864×0.13=0.11232Ω
X 113=X0L 113=0.088×0.13=0.01144Ω