ABB REG670 Applications Manual page 272

Section 8
Impedance protection
266
E
B
B
Pole slip
impedance
movement
IEC06000548 V2 EN
Figure 136: Settings for the Pole slip detection function
The ImpedanceZA is the forward impedance as show in figure 136. 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 150.
UBase
3
=
Z
Base
IBase
EQUATION1883 V1 EN
The ImpedanceZB is the reverse impedance as show in figure 136. ZB should be equal
to the generator transient reactance X'd. The impedance is given in % of the base
impedance, see equation 150.
Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062
Zone 1
X' X
d T
IED
jX
ZA
Zone 2
ZC
TripAngle Zone 1
f
ZB
1MRK 502 071-UEN -
Zone 2
E
A
Z
S
A
WarnAngle
IEC06000548_2_en.vsd
(Equation 150)
Application manual
R