ABB REL670 2.2 IEC - Page 433

IEC06000548_2_en.vsd
IED
B A
E
B
E
A
X’
d
X
T
Z
S
Zone 1 Zone 2
jX
R
ZB
ZA
Pole slip
impedance
movement
Zone 2
Zone 1
WarnAngle
TripAngle
f
ZC
IEC06000548 V2 EN-US
Figure 232: Settings for the Pole slip detection function
The ImpedanceZA is the forward impedance as show in figure 232. ZA should be
the sum of the transformer impedance XT and the equivalent impedance of the
external system ZS. The impedance is given in % of the base impedance, according
to equation 425.
3
Base
UBase
Z
IBase
=
EQUATION1883 V1 EN-US
(Equation 425)
The ImpedanceZB is the reverse impedance as show in figure 232. ZB should be
equal to the generator transient reactance X'd. The impedance is given in % of the
base impedance, see equation 425.
1MRK 506 369-UEN B Section 8
Impedance protection
Line distance protection REL670 2.2 IEC 427
Application manual