正常工作时电缆的护套感应电压计算

3
× 0.037 ]× 442.0 × 0.7
2
2
= 154.7 ×[ j(
0.006 )+ 0.065 ]
= 10.09
∠
5.3
°V
5
6
3
× 0.066 ]× 442.0 × 0.7
2
2
= 154.7 ×[ j(
-0.023 )+ 0.11478 ]
= 18.10
∠
-11.2 ° V
3
5、正三角形排列时，单芯电缆金属护套感 应电压的计算
EA
=
Xm ×( -j 2
-
= 0.04 ×( -j 2
3 )× IB ×
L
3 )× 442.0 × 0.7
= 6.882 ×( -j -
3
)
A BC
= 13.76
∠
-30.0 ° V
EB ＝j Xm × IB ×
EC
=
Xm ×( -j 2
+
= 0.04 ×( -j + 2
= 6.882 ×( -j +
L ＝j 0.044 × 441.99 × 0.7 ＝ 13.76 ∠ 0°V
3 )× IB ×
L
3 )× 442.0 × 0.7
1、元 件计
a＝
b＝
Xm ＝
Y1 ＝
正常工作时单芯电缆的护套感应电压计算（已作连接）
4× π × 10000
f
× ln
2
＝
4× π × 10000
f
× ln
5
＝
4× π × 10000
f
× ln
S rm
＝
Xm + a ＝ 0.044 + 0.044 ＝
4
× 3.1416 × 10000
50
× ln
2
＝
4
× 3.1416 × 10000
50
× ln
5
＝
4 × 3.1416 × 10000
50
× ln
0.27 0.133
＝
0.088
Ω/km
Y2 ＝
Y3 ＝
Y4 ＝ 2、正 常运
IB ＝
Xm +
a ＝ 0.044 + 0.044 ＝
2
2.000
Xm + a +
b
＝ 0.044 +
2
Xm + a -
b
= 37.15
∠
-1.4
°V
4
EB =j( Xm +
a 2
)×
IB
×
L =j( 0.044 + 0.044 )× 442.0 × 0.7 = 20.50 ∠ 0°V 2
EC =
1 ×[ j( 2
Xm
+
b
)+
2
3
× Y3 ]× IB × L
= 1 ×[ j( - 0.044 + 0.101 )+
3
× 0.139 ]× 442.0 × 0.7
2
EB ＝j Xm × IB × L ＝j 0.044 × 441.99 × 0.7 ＝ 13.76 ∠ 0°V
EC =
1 ×[ j( 2
Xm
+
a )+
3
× Y1 ]× IB × L
= 1 ×[ j( - 0.044 + 0.044 )+
3
× 0.088 ]× 442.0 × 0.7
2
= 154.7 ×[ j(
Xm
+
a )-
3
× Y1 ]× IB × L
= 1 ×[ j( - 0.044 + 0.044 )-
3
× 0.088 ]× 442.0 × 0.7
2
= 154.7 ×[ j(
-0.001 )- 0.15249 ]
= 23.59
∠
0.4
°V
0.044 0.101 0.044
Ω/km Ω/km Ω/km
＝ 0.044 +
2
S1 × 1000 = 3× U
80 × 1000 = 3 × 110
0.066
Ω/km
0.044 0.044
+ 0.101 ＝ 2
- 0.101 ＝ 2
442.0 A
3、水平排列时，单芯电缆金属护套感应电压的计算
A
B
C
0.139 0.037
Ω/km Ω/km
EA =
1 ×[ j( 2
3
× 0.066 ]× 442.0 × 0.7
= 18.10
∠
11.2
°V
EB ＝j Xm × IB × L ＝j 0.044 × 441.99 × 0.7 ＝ 13.76 ∠ 0°V
EA =
1 ×[ j( 2
Xm
+
a
)+
2
3
× Y2 ]× IB × L
= 1 ×[ j( - 0.044 + 0.044 )+
3
)
= 13.76
∠
30.0
°V
A
B
C
6、双回路上下排列时，单芯电缆金属护套感应电压的计算
A
EA =
1 ×[ j( 2
Xm
+
b
)-
2
3
= 1 ×[ j( - 0.044 + 0.101 )-
3
2
2
= 154.7 ×[ j(
0.006 )- 0.240 ]
B
C
× Y3 ]× IB × L × 0.139 ]× 442.0 × 0.7
2
2
= 154.7 ×[ j(
0.006 )- 0.065 ]
= 10.09
∠
-5.3
°V
EB =j( Xm +
a 2
)×
IB
×
L =j( 0.044 + 0.044 )× 442.0 × 0.7 = 20.50 ∠ 0°V 2
EC =
1 ×[ j( 2
Xm
+
b
)+
2
3
× Y4 ]× IB × L
= 1 ×[ j( - 0.044 + 0.101 )+
-0.001 )+ 0.15249 ]
= 23.59
∠
-0.4
°V
4、直角三角形排列时，单芯电缆金属护套感 应电压的计算
EA =
1 ×[ j( 2
Xm
+
a
)-
2
= 1 ×[ j( - 0.044 + 0.044 )-
2
2
= 154.7 ×[ j(
-0.023 )+ 0.11478 ]
A
BC
3
Biblioteka Baidu
× Y2 ]× IB × L
2
2
= 154.7 ×[ j(
0.006 )+ 0.240 ]
= 37.15
∠
1.4
°V
A
B
C
7、双回路上下排列时，单芯电缆金属护套感应电压的计算
C
B
A
EA =
1 ×[ j( 2
Xm
+
b
)-
2
3
× Y4 ]× IB × L
= 1 ×[ j( - 0.044 + 0.101 )-
3
× 0.037 ]× 442.0 × 0.7