
⎯
135
⎯
6 F 2 S 0 8 4 6
Distance calculation for earth fault (in the case of A-phase earth fault)
x
1
=
I
m
(V
a
⋅
I
α
")
×
L
{I
m
(R
1
⋅
I
α
⋅
I
α
" + R
0
⋅
I
0S
⋅
I
α
" + R
0m
⋅
I
0m
⋅
I
α
") + R
e
(X
1
⋅
I
α
⋅
I
α
" + X
0
⋅
I
0S
⋅
I
α
" + X
0m
⋅
I
0m
⋅
I
α
")}
×
K
a
where,
Va = fault voltage
I
α
= fault current = (2Ia
−
Ib
−
Ic)/3
I
α
" = change of fault current before and after fault occurrence
=
2Ia
−
Ib
−
Ic
3
−
2ILa
−
ILb
−
ILc
3
Ia, Ib, Ic = fault current
ILa, ILb, ILc = load current
I0s = zero sequence current
I0m = zero sequence current of parallel line
R1 = resistance component of line positive sequence impedance
X1 = reactance component of line positive sequence impedance
R0 = resistance component of line zero sequence impedance
X0 = reactance component of line zero sequence impedance
R0m = resistance component of line mutual zero sequence impedance
X0m = reactance component of line mutual zero sequence impedance
Ka = impedance imbalance compensation factor
Im( ) = imaginary part in parentheses
Re( ) = real part in parentheses
L = line length (km)
Equations (1) and (2) are general expressions when lines are treated as having lumped constants
and these expressions are sufficient for lines within 100 km. For lines exceeding 100 km,
influences of the distributed capacitance must be considered. For this fault locator, the following
equation is used irrespective of line length to find the compensated distance
x
2
with respect to
distance
x
1
which was obtained in equation (1) or (2).
x
2
=
x
1
−
k
2
⋅
x
1
3
3 (3)
where,
k = propagation constant of the protected line = 0.001km
-1
(fixed)
2.7.3 Starting
Calculation
Calculation of the fault location is initiated by one of the following tripping signals.
•
command protection trip
•
zone 1 trip
•
zone 2 trip
•
zone 3 trip
(2)
Summary of Contents for GRZ100 B Series
Page 264: ... 263 6 F 2 S 0 8 4 6 Appendix A Block Diagram ...
Page 271: ... 270 6 F 2 S 0 8 4 6 ...
Page 272: ... 271 6 F 2 S 0 8 4 6 Appendix B Signal List ...
Page 307: ... 306 6 F 2 S 0 8 4 6 ...
Page 308: ... 307 6 F 2 S 0 8 4 6 Appendix C Variable Timer List ...
Page 310: ... 309 6 F 2 S 0 8 4 6 Appendix D Binary Input Output Default Setting List ...
Page 321: ... 320 6 F 2 S 0 8 4 6 ...
Page 322: ... 321 6 F 2 S 0 8 4 6 Appendix E Details of Relay Menu and LCD Button Operation ...
Page 331: ... 330 6 F 2 S 0 8 4 6 ...
Page 340: ... 339 6 F 2 S 0 8 4 6 Appendix G Typical External Connections ...
Page 377: ... 376 6 F 2 S 0 8 4 6 ...
Page 384: ... 383 6 F 2 S 0 8 4 6 Appendix J Return Repair Form ...
Page 388: ... 387 6 F 2 S 0 8 4 6 Customer Name Company Name Address Telephone No Facsimile No Signature ...
Page 389: ... 388 6 F 2 S 0 8 4 6 ...
Page 390: ... 389 6 F 2 S 0 8 4 6 Appendix K Technical Data ...
Page 401: ... 400 6 F 2 S 0 8 4 6 ...
Page 402: ... 401 6 F 2 S 0 8 4 6 Appendix L Symbols Used in Scheme Logic ...
Page 405: ... 404 6 F 2 S 0 8 4 6 ...
Page 406: ... 405 6 F 2 S 0 8 4 6 Appendix M Example of Setting Calculation ...
Page 417: ... 416 6 F 2 S 0 8 4 6 ...
Page 418: ... 417 6 F 2 S 0 8 4 6 Appendix N IEC60870 5 103 Interoperability and Troubleshooting ...
Page 434: ... 433 6 F 2 S 0 8 4 6 Appendix P Inverse Time Characteristics ...
Page 437: ... 436 6 F 2 S 0 8 4 6 ...
Page 438: ... 437 6 F 2 S 0 8 4 6 Appendix Q Failed Module Tracing and Replacement ...
Page 444: ... 443 6 F 2 S 0 8 4 6 Appendix R Ordering ...
Page 447: ......