ABB REL670 2.2 IEC - Page 417

1
1
S
CO SA
B
A
Z
Z Z
E
E
= -
+
EQUATION1340 V1 EN-US (Equation 405)
In particular cases, when
A B
E E=
EQUATION1342 V1 EN-US (Equation 406)
The center of oscillation resides on the impedance point according to equation 407.
( )
1
7.43 33.9
2
S
CO SA
Z
Z Z j= - = + W
EQUATION1341 V1 EN-US (Equation 407)
1MRK 506 369-UEN B Section 8
Impedance protection
Line distance protection REL670 2.2 IEC 411
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