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Re
Re
Re
Im
K
A
X
A
A
u
m
( )
= +
( )
⋅
( )
+
( )
1
0
2
2
2
EQUATION1287 V3 EN-US
(Equation 330)
The imaginary component of the same factor is equal to equation
( )
( )
( )
( )
2
0
2
2
Im
Im
Re
Im
m
U
A X
K
A
A
×
=
+
é
ù
é
ù
ë
û
ë
û
EQUATION1288 V2 EN-US
(Equation 331)
Ensure that the underreaching zones from both line ends will overlap a sufficient amount (at
least 10%) in the middle of the protected circuit.
7.12.2.7
Tapped line application
GUID-740E8C46-45EE-4CE8-8718-9FAE658E9FCE v1
GUID-7AA566A4-B6E9-41A7-9927-4DAB50BE8D1A v1
C
B
BC
IEC09000160-3-en.vsd
A
IEC09000160 V3 EN-US
Figure 195: Example of tapped line with Auto transformer
This application gives rise to similar problem that was highlighted in section
, that is increased measured impedance due to fault current infeed. For
example, for faults between the T point and B station the measured impedance at A and C will
be
Z
A
=Z
AT
+ ·Z
TF
I
A
+ I
C
I
A
DOCUMENT11524-IMG3509 V3 EN-US
(Equation 332)
1MRK 505 343-UEN B
Section 7
Impedance protection
313
Application manual
Содержание Relion 670 series
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