ABB Relion 650 Series Technical Manual page 117

1MRK 506 326-UUS B
I ·Z
AB
-
I ·ZRev
AB
ANSI09000117 V1 EN-US
Figure 59: Simplified offset mho characteristic and voltage vectors for phase A-to-B fault.
Operation occurs if 90≤β≤270.
Offset mho, forward direction
When forward direction has been selected for the offset mho, an extra criteria beside the one for
offset mho (90<β<270) is introduced, that is the angle φ between the voltage and the current
must lie between the blinders in second quadrant and fourth quadrant. See figure 60. Operation
occurs if 90≤β≤270 and
where
ArgDir
ArgNegRes
β
The directional information is brought to the mho distance measurement from the mho
directional element as binary coded information to the input DIRCND. See Directional impedance
quadrilateral and mho (ZDNRDIR) for information about the mho directional element.
Line distance protection REL650
Technical manual
I ·X
AB
ß
V
ArgDir≤φ≤ArgNegRes .
is the setting parameter for directional line in fourth quadrant in the directional
element, ZDNRDIR.
is the setting parameter for directional line in second quadrant in the directional
element, ZDNRDIR.
is calculated according to equation
© Copyright 2011 ABB Power Grids. All rights reserved
-
=
V I ·Z
Vcomp1
AB AB
=
Vcomp2=V I ·Z =V
F F AB
I ·R
AB
ANSI09000117-1-en.vsd
Section 5
Impedance protection
SEMOD154224-249 v4
111