ABB RELION RET670 - Page 665

0.2 0.4 0.6
-0.2
0.6
0.8
0.8
1
D
ILowSet
B
A
C
0.4
0.2
0
1.2
1.4
-0.4
-0.6
-0.8
-rca
Operating Region
Q [pu]
P [pu]
rca
V
PS
I
PS
ILowSet
Operating region
en05000535_ansi.vsd
ANSI05000535 V1 EN-US
Figure 301: Loss of excitation
1MRK 504 163-UUS A Section 12
Multipurpose protection
Transformer protection RET670 2.2 ANSI 659
Application manual