ABB REG670 - Page 392

1. STFW=1 when tip of I2 phasor (operating quantity magnitude) is in forward area,
see fig 165 (Operating quantity magnitude is bigger than setting I>Dir)
2. STRV=1 when tip of I2 phasor (operating quantity magnitude) is in the reverse
area, see fig
165. (Operating quantity magnitude is bigger than 60% of setting
I>Dir)
These signals must be used for communication based fault teleprotection
communication schemes (permissive or blocking).
Simplified logic diagram for directional supervision element with integrated
directional comparison step is shown in figure 166:
X
a
b
a>
b
I>Dir
FORWARD_Int
REVERSE_Int
BLOCK
STAGE1_DIR_Int
0.6
X
0.4
a
b
a>
b
AND
STAGE3_DIR_Int
STAGE4_DIR_Int
STAGE2_DIR_Int
OR
STRV
UPolMin
IPolMin
AngleRCA
D
i
r
e
c
t
i
o
n
a
l
C
h
a
r
a
c
t
e
r
i
s
t
i
c
FWD
RVS
AND
AND
AND
STFW
FORWARD_Int
REVERSE_Int
AND
IEC07000067-4.vsd
|
|
Iop
UPol
Iop
IEC07000067-4 V2 EN
Figure 173: Simplified logic diagram for directional supervision element with integrated directional comparison
step
Section 8 1MRK502052-UEN B
Current protection
386
Technical manual