ABB REO 517, Руководство по применению

Страница: 342 / 440

332
Fault locator (FLOC)
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For double lines, the fault equation is:
(Equation 68)
Because the D
A
distribution factor according to equation 66 or 69 is a function of p, the
general equation 68 can be written in the form:
(Equation 70)
Where:
(Equation 71)
(Equation 72)
(Equation 73)
Where:
I
0P
is a zero sequence current of the parallel line,
Z
0M
is a mutual zero sequence impedance and
D
A
is the distribution factor of the parallel line, which is:
(Equation 69)
U
A
I
A
p Z
1L
I
FA
D
A
--------
R
F
I
0P
Z
0M
⋅
+
⋅
+
⋅ ⋅
=
D
A
1 p –
( )
Z
A
Z
A L
Z
B
+ +
( )
Z
B
+
⋅
2 Z
A
Z
L
2 Z
B
⋅
+ +
⋅
-----------------------------------------------------------------------------
=
p
2
p K
1
K
2
K
3
R
F
⋅
– +
⋅
– 0 =
K
1
U
A
I
A
Z
L
⋅
----------------
Z
B
Z
L
Z
A DD
+
--------------------------- 1
+ + =
K
2
U
A
I
A
Z
L
⋅
----------------
Z
B
Z
L
Z
A DD
+
---------------------------
1 +
 
 
⋅
=
K
3
I
F A
I
A
Z
L
⋅
----------------
Z
A
Z
B
+
Z
1
Z
A DD
+
--------------------------- 1
+
 
 
⋅
=