Siemens SINAMICS DCM - Dimensioning of the Converter Transformer

12-pulse series connection
4.2 Configuration
12-pulse applications
Compact User Manual, 09/2015, A5E34871844H
33
4.2.3
Dimensioning of the converter transformer
Application with three-winding converter transformer
1) Transformer
2) Overvoltage protection
3) Insulation monitoring
4) SINAMICS DCM master
5) SINAMICS DCM slave
6) DC motor
8) Parallel interface
9) Symmetry resistor
U
N
= rated voltage of the line supply connected at the converter input
I
d
= direct current through both SINAMICS DCM devices and motor
Figure 4-5 Converter transformer dimensioning at higher voltage level
Transformer: A separate three-winding converter transformer is used to connect to the
network of a higher voltage level.
Preferred vector groups for the transformer: Dd0Dy11, Dd6Dy5, Yy0Yd11, Yy6Yd5,, u
k
=
4 % to 6 %
It is important to ensure that the three-phase current system on the slave device lags behind
that of the master device by 30°.
Transformer type rating: S
T
= U
N
× 1,35 × 1,05 × I
d
× 2