ABB Relion 670 series - Page 472

ZA
ZB
Zload
R
X
en07000016.vsd
IEC07000016 V1 EN
Figure 240: Simplified figure to derive StartAngle
0 0
arctan arctan arctan + arctan = 7.1 + 5.4
0.25 0.19
13
2 2
³ = »
ZB ZA
angleStart +
Zload Zload
EQUATION1977 V2 EN
(Equation 442)
In case of minor damped oscillations at normal operation we do not want the protection to
start. Therefore we set the start angle with large margin.
Set StartAngle to 110°.
For the TripAngle it is recommended to set this parameter to 90° to assure limited stress
for the circuit breaker.
If the centre of pole slip is within the generator block set N1Limit to 1 to get trip at first pole
slip.
If the centre of pole slip is within the network set N2Limit to 3 to get enable split of the
system before generator trip.
Section 8 1MRK 506 369-UUS -
Impedance protection
466 Line distance protection REL670 2.2 ANSI
Application manual