ABB Relion 650 Series Technical Manual page 130

Section 5
Impedance protection
V2MinOp
|V |>
2
where:
V1MinOP and V2MinOp
The positive sequence voltage V
If there is a three-phase fault, there will not be any release of the individual phase signals, even if
the general conditions for V
Phase-to-ground and phase-to-phase-to-ground-fault detection
The detection of phase-to-ground and phase-to-phase-to-ground fault (US patent 5390067) is
based on two conditions:
1. Angle relationship between V
2. Angle relationship between V
The condition 1 determines faulty phase at single phase-to-ground fault by determine the angle
between V
BG sector
200°
ANSI06000384 V1 EN-US
Figure 68: Condition 1: Definition of faulty phase sector as angle between V
The angle is calculated in a directional function block and gives the angle in radians as input to the
V and I
2 0
done by the directional element. The fault is classified as forward direction if the angle between V
and I lies between 20 to 200 degrees, see figure 69.
0
124
are the setting parameters for positive sequence and negative
sequence minimum operate voltages
1
and V
2
and I
2
and V
2
and I .
2 0
80°
CG sector
AG sector
function block. The input angle is released only if the fault is in forward direction. This is
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A in figure 67 above is reference.
are fulfilled.
1
0
1
V2A
(Ref)
320°
en06000384_ansi.vsd
1MRK 506 326-UUS B
SEMOD153832-135 v4
and I
2 0
Line distance protection REL650
Technical manual
0