Line Harmonics Filter (Lhf) - Siemens SINAMICS G130 Engineering Manual

Fundamental Principles and System Description
Engineering Information
Converters connected in parallel
Another constellation which requires the use of line reactors is the parallel connection of converters where the
paralleled rectifiers are directly connected at both the line side and the DC link sides. This applies to both G150
paralleled units and to parallel connections of S120 Basic Line Modules and S120 Smart Line Modules if these
involve a 6-pulse connection. The line reactors provide for balanced current distribution and ensure that no individual
rectifier is overloaded by excessive current imbalances.
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Line Harmonics Filter (LHF)

Line Harmonics Filters LHF are passive filters that mainly absorbe the 5
6-pulse rectifiers and in this way significantly reduce the harmonic effects on the supply system to the significantly
lower level associated with 12-pulse rectifier circuits.
They can be used on SINAMICS G130 and G150 units and are installed between the mains supply connection and
the converter.
Line Harmonics Filters produce losses, which slightly reduce the efficiency of the converter. The converter efficiency
drops by approximately 0.3 % from typically 98.0 % to 97.7 % when a Line Harmonics Filter is used with either
SINAMICS G130 or G150 converters. The relatively large reduction in the harmonics compared to 6-pulse converters
without LHFs is associated with a relatively small reduction of the efficiency.
In order to reduce the harmonics on the supply, SINAMICS S150 converters with a pulsed Active Infeed can also be
used, as an alternative to SINAMICS G130 / G150 with Line Harmonics Filters. This would produce sligthtly lower
harmonics on the line side but the efficiency of the converter is quite noticeably reduced to approximately 96%. Thus,
from a purely energy-related point of view, this alternative solution cannot be recommended.
Line Harmonics Filters LHF require the following additional components:
•
Line-side fuse protection of the Line Harmonics Filter,
•
A main contactor or a circuit breaker on the converter side
•
A converter-side line reactor with a relative short-circuit voltage of 2 %
Additional components required in conjunction with Line Harmonics Filters LHF
The following points must also be noted:
Each converter must have its own Line Harmonics Filter LHF. It is not permitted to operate more than one low power
converter on a single high output Line Harmonics Filter LHF.
The power rating of the converter must not be less than two grades lower than that of the Line Harmonics Filter LHF,
otherwise the mismatching of the line reactors will influence the resonance frequency on the converter side too much,
thereby reducing the effectiveness of the filter. With this in mind, Line Harmonics Filters are available for the following
converter output power ratings:
Supply voltage
3AC 380 V – 480 V
3AC 500 V – 600 V
3AC 660 V – 690 V
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© Siemens AG
Rated converter power
≥ 160 kW
≥ 110 kW
≥ 160 kW
th th
and the 7 harmonic in the line currents of