Siemens siprotec SJ62, Руководство пользователя

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2.19 Synchronism and Voltage Check 25 (7SJ64 only)
294
SIPROTEC 4, 7SJ62/63/64 Handbuch
C53000-G1140-C147-A, Edition 07.2015
The parameter
Balancing V1/V2
(address 6x21) can be set to account for different
VT ratios of the two parts of the power system (see example in Figure 2-105).
If a transformer is located between the system parts to be synchronized, its vector
group can be accounted for by angle adjustment so that no external adjusting mea-
sures are required. Parameter
ANGLE ADJUSTM.
(address 6x22A) is used to this end.
The phase angle from V
1
to V
2
is evaluated positively.
Example: (see also Figure 2-105):
Busbar 400 kV primary; 110 V secondary
Feeder 220 kV primary; 100 V secondary
Transformer 400 kV/220 kV; vector group Dy(n)5
The transformer vector group is defined from the high side to the low side. In the ex-
ample, the reference voltage transformers (V
1
) are the ones of the transformer high
side, i.e. the setting angle is 5 x 30
°
(according to vector group), that is 150
°
:
Address 6x22A:
ANGLE ADJUSTM.
=
150 °
.
The reference voltage transformers supply 100 V secondary for primary operation at
nominal value while the feeder transformer supplies 110 V secondary. Therefore, this
difference must be balanced:
Address 6x21:
Balancing V1/V2
= 100 V/110 V =
0.91
.
Figure 2-105 Busbar voltage measured accross transformer
Connections 7SJ64 provides three voltage inputs for the connection of voltage V
1
and one voltage
input for voltage V
2
(see Figure 2-106 and Figure 2-105). According to definition, the
three-phase voltage is the reference voltage V
1
. To compare the three-phase voltage
V
1
with voltage V
2
correctly, the connection type of voltage V
2
must be signalled to the
device. Address
CONNECTIONof V2
assumes this task (parameter 6x23).
If three phase-to-ground voltages are connected to side V
1
, then any phase-phase or
phase-to-ground voltage can be used and configured as voltage to be synchronized
V
2
. If two phase-phase voltages are connected in V-connection to side V
1
, then the