ABB Relion 670 series - Page 400

R
X
Underexcitation Protection
Restrain area
DirAngle
XoffsetDirLine
Z (apparent impedance)
en06000457.vsd
IEC06000457 V1 EN-US
Figure 211: Impedance constructed as XoffsetDirLine in LEXPDIS (40) protection
LEXPDIS (40) function is schematically described in figure 212.
en06000458-
2_ansi.vsd
Apparent
impedance
calculation
Positive
sequence
current
phasor
Positive
sequence
voltage
phasor
Z
Z in
Z1 char.
Z in
Z2 char.
Dir.
Restrain
OR
Dir.Restrain Enabled
AND
AND
pickupZ1
0
TripZ1
TripZ2
tZ1
tZ2
0
pickupZ2
ANSI06000458 V2 EN-US
Figure 212: Simplified logic diagram of LEXPDIS (40) protection
Section 7 1MRK 502 066-UUS B
Impedance protection
394
Technical manual