Siemens siprotec SJ62, Руководство пользователя

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2 Functions
99
SIPROTEC 4, 7SJ62/63/64 Handbuch
C53000-G1140-C147-A, Edition 07.2015
Figure 2-23 Cross-polarized voltages for direction determination
The following table shows the assignment of measured values for the determination
of fault direction for various types of pickups.
Table 2-6 Measured values for the determination of fault direction
1)
or 3 · V
0
= |VA + VB + VC|, depending on type of connection for the voltages
Direction Determi-
nation of Direction-
al Phase Elements As already mentioned, the direction determination is performed by determining the
phase angle between the fault current and the reference voltage. In order to satisfy
different network conditions and applications, the reference voltage can be rotated
through an adjustable angle. In this way, the vector of the rotated reference voltage
can be closely adjusted to the vector of the fault current in order to provide the best
possible result for the direction determination. Figure 2-24 clearly shows the relation-
ship for the directional phase elements based on a single-pole ground fault in Phase
A. The fault current
I
scA
follows the fault voltage by the fault angle
ϕ
sc
. The reference
voltage, in this case V
BC
for the directional phase element A, is rotated through the
PICKUP Directional Element
A B C N
Current Voltage Current Voltage Current Voltage Current Voltage
A
I
A
V
B
– V
C
— — — — — —
B — —
I
B
V
C
– V
A
— — — —
C — — — —
I
C
V
A
– V
B
— —
N — — — — — —
I
N
V
N
1)
A, N
I
A
V
B
– V
C
— — — —
I
N
V
N
1)
B, N — —
I
B
V
C
– V
A
— —
I
N
V
N
1)
C, N — — — —
I
C
V
A
– V
B
I
N
V
N
1)
A, B
I
A
V
B
– V
C
I
B
V
C
– V
A
— — — —
B, C — —
I
B
V
C
– V
A
I
C
V
A
– V
B
— —
A, C
I
A
V
B
– V
C
— —
I
C
V
A
– V
B
— —
A, B, N
I
A
V
B
– V
C
I
B
V
C
– V
A
— —
I
N
V
N
1)
B, C, N — —
I
B
V
C
– V
A
I
C
V
A
– V
B
I
N
V
N
A, C, N
I
A
V
B
– V
C
— —
I
C
V
A
– V
B
I
N
V
N
1)
A, B, C
I
A
V
B
– V
C
I
B
V
C
– V
A
I
C
V
A
– V
B
— —
A, B, C, N
I
A
V
B
– V
C
I
B
V
C
– V
A
I
C
V
A
– V
B
I
N
V
N
1)