Siemens SINAMICS G130 Engineering Manual page 50

Fundamental Principles and System Description
Engineering Information
•
When using 6-pulse rectifier circuits (G130, G150, S120 Basic Line Modules and S120 Smart Line Modules), the
limits can generally be maintained only if a very low percentage of the total transformer load is made up of
converter load. Typical constellations with 6-pulse rectifiers cannot maintain the limits due to excessive harmonic
currents with harmonic numbers 5, 7, 11 and 13.
•
When using 6-pulse rectifier circuits (G130, G150) with Line Harmonics Filters, the limits can always be
maintained.
•
When using 12-pulse rectifier circuits (G150 in the higher power range with two parallel connected converters,
S120 Basic Line Modules or S120 Smart Line Modules supplied by a three-winding transformer) the limits can
only be maintained with a relatively strong supply and, correspondingly, a large relative short-circuit power.
Configurations with 12-pulse rectifier circuits connected to weak supplies with small relative short-circuit power
do not maintain the limits due to high harmonic currents with the harmonic numbers 11 and 13.
•
When self-commutated IGBT rectifiers / regenerative units (S150, S120 Active Line Modules) are used, the limits
can always be maintained.
If 6-pulse rectifier circuits without Line Harmonics Filters or 12-pulse rectifier circuits are used, an exact calculation of
the harmonic effects on the supply should always be with the supplementary conditions of the individual plant
constellation.
SINAMICS Engineering Manual – May 2008
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