Figure 72: Reverse Impedance Reach Line Construction; Figure 73: Resistive Reach Of Phase Elements; Phase Fault Resistive Reach Line - GE MiCOM P40 Agile Technical Manual

Chapter 7 - Distance Protection
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Figure 72: Reverse impedance reach line construction

For an Offset zone, Z' is the settable reverse reach. For a directional zone Z' is a fixed percentage (either 25% or
100%) of the forward reach (Z) in the opposite direction.
The signals provided to the comparator are:
S = V - I.Z'
1
Ð -3°
S = I.
2
Impedance on the tripping side of the Reverse Impedance Reach line is detected when the angle between S1 and
S2 is greater than 0°.
3.3.3

PHASE FAULT RESISTIVE REACH LINE

Refer to the following figure:
Network
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Figure 73: Resistive reach of phase elements

164
+jX
+Z' V / I
V / I - Z'
IED
Dist
Bus
Z
F
+R
-3°

V I
Half of the loop
A
R
LP B
C
P543i/P545i
Line
P54x1i-TM-EN-1