Siemens SINAMICS DCM Manual page 576

10.27.4 6-pulse series connection: controlled converter + uncontrolled converter
Topology
The following diagram shows the topology of a 6-pulse series connection of a SINAMICS
DCM 2-quadrant unit and a diode rectifier. (thyristor bridge B6 + diode rectifier)
Remark:
The incoming AC voltage of the controlled converter should be 10% to 15% higher than that
at the uncontrolled converter, in order that the current can be reliably reduced down to 0.
Figure 10-84 6-pulse series connection: controlled + uncontrolled rectifier
The instructions for dimensioning the balancing resistors can be found in an FAQ (for the
link, see the Preface).
SINAMICS DCM DC Converter
Operating Instructions, 02.2015, A5E34763375/RS-AA/001
10.27 Connecting units in parallel and in series
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Descriptions of functions
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