Siemens 6MD85, Manual

Page: 497 / 1256

i
i
NOTE
Make sure that you configure the parameter
Max load current
on the voltage controller on the trans-
former T
1
to 200 %, as this summation load current is used for the line compensation.
Parameter: Max load current
•
Default setting
(_:14011:127) Max load current
=
100.0 %
With the setting of the parameter
Max load current
, you can prevent the voltage at the transformer from
becoming too high in the event of extraordinarily high load current. If the load current exceeds the set value,
no additional load-current compensation is calculated.
For setting the parameter
Line drop compensation
=
LDC-XandR
, consider the following parameters:
Parameter: R line
•
Default setting
(_:14011:153) R line
=
0.00 Ω
With the
R line
parameter, you to set the ohmic resistance of the line.
Parameter: X line
•
Default setting
(_:14011:154) X line
=
0.00 Ω
With the
X line
parameter, you set the reactance for the line to be protected.
In order to determine the voltage drop by the line, entering the parameter
R line
and
X line
is necessary
for the procedure
Line drop compensation
=
LDC-XandR
. If the primary values are known and you
would like to set the secondary values, use the following formula for the calculation:
[fo-I-V-Ratio-250214, 1, en_US]
As an example, calculate X
sec
with the following parameters:
Current transformer ratio : 1000 A/1 A
Voltage transformer ratio : 380 kV/0.1 kV
X
prim
: 21 Ω
Therefore, the result for X
sec
is:
[fo-I-V-Ratio_Value-250214, 1, en_US]
If you are implementing a parallel control with the X and R compensation, then the X value is negative and
considers the voltage rising from the busbar to the transformer.
Control Functions
6.9 Voltage Controller
SIPROTEC 5, High-Voltage Bay Controller, Manual 497
C53000-G5040-C015-9, Edition 11.2017