ABB RELION REX640 Technical Manual page 481

1MRS759142 C
REX640
Technical Manual
Unearthed
100
90
Rf = 500 ohm
80
Rf = 2500 ohm
70
Rf = 5000 ohm
60
Rf = 10000 ohm
50
40
30
20
10
0
0 10 20 30 40 50 60 70 80 90 100
Total earth f ault current (A), Rf = 0 ohm
GUID-18749064-8F4D-4FBE-8A5D-49B90EDCAA5E V1 EN
Figure 259: Influence of fault resistance on the residual voltage magnitude in 10
kV unearthed and compensated networks. The leakage resistance is
assumed to be 30 times larger than the absolute value of the
capacitive reactance of the network. Parallel resistor of the
compensation coil is assumed to be disconnected.
Unearthed
100
90
Rf = 500 ohm
80
Rf = 2500 ohm
70
Rf = 5000 ohm
60
Rf = 10000 ohm
50
40
30
20
10
0
0 10 20 30 40 50 60 70 80 90 100
Total earth f ault current (A), Rf = 0 ohm
GUID-14137070-AB69-4CDD-A0A5-A811B6DDDF4A V1 EN
Figure 260: Influence of fault resistance on the residual voltage magnitude in 15
kV unearthed and compensated networks. The leakage resistance is
assumed to be 30 times larger than the absolute value of the
capacitive reactance of the network. Parallel resistor of the
compensation coil is assumed to be disconnected.
Unearthed
100
90
80 Rf = 500 ohm
70 Rf = 2500 ohm
Rf = 5000 ohm
60
Rf = 10000 ohm
50
40
30
20
10
0
0 10 20 30 40 50 60 70 80 90100
Total earth f ault current (A), Rf = 0 ohm
GUID-9F57992B-39D0-40D8-A2B0-5BB300B29AF9 V1 EN
Figure 261: Influence of fault resistance on the residual voltage magnitude in 20
kV unearthed and compensated networks. The leakage resistance is
assumed to be 30 times larger than the absolute value of the
capacitive reactance of the network. Parallel resistor of the
compensation coil is assumed to be disconnected.
Protection functions
Resonance, K = 1
100
90
80
70
60
50
40
30
20
10
0
0 10 20 30 40 50 60 70 80 90 100
Total earth f ault current (A), Rf = 0 ohm
Resonance, K = 1
100
90
80
70
60
50
40
30
20
10
0
0 10 20 30 40 50 60 70 80 90100
Total earth f ault current (A), Rf = 0 ohm
Resonance, K = 1
100
90
80
70
60
50
40
30
20
10
0
0 10 20 30 40 50 60 70 80 90 100
Total earth f ault current (A), Rf = 0 ohm
Section 4
Over/Under-Compensated, K = 1.2/0.8
100
90
80
70
60
50
40
30
20
10
0
0 10 20 30 40 50 60 70 80 90 100
Total earth f ault current (A), Rf = 0 ohm
Over/Under-Compensated, K = 1.2/0.8
100
90
80
70
60
50
40
30
20
10
0
0 10 20 30 40 50 60 70 80 90100
Total earth f ault current (A), Rf = 0 ohm
Over/Under-Compensated, K = 1.2/0.8
100
90
80
70
60
50
40
30
20
10
0
0 10 20 30 40 50 60 70 80 90 100
Total earth f ault current (A), Rf = 0 ohm
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