Siemens Sinamics SM150 6SL3845-2NN41-8AD0, Operating And Installation Instructions

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Consider the following properties during the configuration:
● Short-circuit voltage u
k
≥ 10% (in relation to 10 MVA)
● Transformer taps for voltage adjustments:
2 x 2.5%.
The winding transformer taps are normally located on the primary side of the transformer.
● The voltages and insulation for the secondary-side windings must be dimensioned as
shown in the following table:
Connection Single connection
Circuit version Basic connection, 12-pulse infeed Series connection of the Basic Line
Module
Infeed transformers 1 three-winding transformer 2 three-winding transformers
Recommended vector group Dy5 Dd0 Dy5 Dd0
with primary shift + 7.5°
Dy5 Dd0
with primary shift - 7.5°
Drive output voltage
[kV]
Test voltage
[kV]
1)
Transformer secondary voltage
(no-load voltage)
[kV]
3.3 33.6 2 x 1.7
2)
2 x 0.85 (2x)
3)
1)
The specified voltage is the required impulse withstand / test voltage for the transformer
secondary windings with respect to ground. Because the transformers generally have
temperature evaluation systems in the windings, the specified test voltage is required for
strengthened insulation. If no control circuits have been installed in the windings, the test
voltage in accordance with the basic insulation is sufficient.
2)
Basic connection
3)
Option
A two-winding transformer is required for each Active Line Module. When two complete drive
units are connected in parallel, a three-winding transformer with shifted windings can be used
for suppressing line harmonics.
Consider the following properties during the configuration:
● Transformer secondary voltage: 3.3 kV
● Minimum leakage inductance: 1 mH
(short-circuit voltage
u
k
=15% to 28% depending on transformer output)
This value includes all the inductance between the line and the converter: Line short-circuit
inductance, transformer inductance, reactor inductance.
● Transformer taps for voltage adjustments: 2 x ± 2.5
The winding taps are usually located on the high voltage side of the transformer.
Description
3.5 Description of the components
SINAMICS SM150 6SL3845-2NN41-8AD0
38
Operating Instructions Rev.201908010908 EXAMPLE