Sel 411L - Figure 3.75 Summary Command Output Showing the TW Fault Location Result

P.3.126
SEL-411L Relay Protection Manual Date Code 20151029
Protection Functions
Fault Location
In installations where the differential communication channel is not available,
fault location can be computed using the following:
➤ Traveling wave arrival information in the TW COMTRADE
header file from both terminals (see Example 8.3)
➤ Configure a DNP client to receive the wave arrival information
from both terminals and use Equation 3.65
Figure 3.75 shows the summary command output showing the traveling wave.
==>>SUM
Relay 1 Date: 08/21/2013 Time: 14:04:37.661
Station 1 Serial Number: 1131860535
Event: BG T FLM: TW Time Source: HIRIG
TW Location: 94.47(mi) Z-Based Location: 97.36(ME) From: LOCAL
Event Number: 10002 Shot 1P: 0 Shot 3P: 0 Freq: 60.00 Group: 1
Targets: INST COMM B_PHASE GND 87L 50PICUP
Breaker 1: CLOSED Trip Time: 14:04:37.661
Breaker 2: CLOSED Trip Time: 14:04:37.661
PreFault: IA IB IC IG 3I2 VA VB VC V1mem
MAG(A/kV) 0 0 0 0 0 0.003 0.005 0.006 0.000
ANG(DEG) 138.0 48.4 -134.9 135.7 -47.7 156.7 -171.4 134.9 -52.4
Fault:
MAG(A/kV) 0 1610 0 1610 961 66.786 45.173 66.896 59.974
ANG(DEG) 104.0 160.4 179.9 160.4 40.4 0.0 -115.7 120.0 1.6
87 Differential Currents
PreFault: IA IB IC IQ IG
MAG(pu) 0.00 0.00 0.00 0.00 0.00
ANG(DEG) -170.9 -157.0 -73.6 149.3 -140.8
Fault:
MAG(pu) 0.00 4.46 0.00 3.53 4.46
ANG(DEG) 139.2 -178.7 -28.5 29.5 -178.7
==>>
Figure 3.75 Summary Command Output Showing the TW Fault Location Result
Impedance Based
This section explains the impedance-based fault location methods using
differential current and local current polarization. The relay incorporates a
multi-ended fault location algorithm to improve the numerical accuracy of
fault location and to identify faulted line sections in three- and four-terminal
applications.
Explained first is the principle of the double-ended fault location the relay
uses and then provides implementation details for three- and four-terminals
lines in the master-master and master-outstation modes.
Figure 3.76 provides a general fault diagram. We can calculate per-unit fault
location as follows:
Equation 3.66
where:
Im
= the imaginary part of a complex number
* = the complex conjugate
I
L
= the relay loop current consisting of the three-phase currents
per principles of distance protection based on the fault type
V
L
= the loop voltage at the relay location corresponding to the
loop current
Z
L
= the positive-sequence impedance of the line
I
F
= the loop current at the fault location
m
Im V
L
I
F
*
• 
Im I
L
Z
L
I
F
*
• • 
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