Harmonic Currents Of 6-Pulse Rectifier Circuits With Line Harmonics Filter - Siemens SINAMICS G130 Engineering Manual

Fundamental Principles and System Description
Engineering Information
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Typical current harmonic spectrum with Smart Infeed in
rectifier (motor) operation with a line reactor of 4 %
(specified in %)
th
The 5 current harmonic, which is very strong in rectifier (motor) operation, is reduced considerably during
regenerative operation. Therefore all remaining harmonics increase slightly. Due to the considerable decrease in the
th
5 current harmonic, there is a slightly lower Total Harmonic Distortion factor THD(I) in regenerative operation. So it
is sufficient for harmonics calculations with the SINAMICS Smart Infeed to consider only the worse rectifier (motor)
operation.
The following diagrams show the typical line side currents with SINAMICS Smart Infeed in rectifier (motor) operation
and regenerative operation.
Typical line current with Smart Infeed in rectifier operation

Harmonic currents of 6-pulse rectifier circuits with Line Harmonics Filter

A Line Harmonics Filter LHF is a passive filter that mainly absorbes the 5
6-pulse rectifiers and in this way significantly reduces the harmonic effects on the supply. It is installed between the
line supply connection and converter and can be used on SINAMICS G130 and G150. Line Harmonics Filter LHF
require a line reactor with a relative short-circuit voltage of u
information about the operating principles and usage limitations of the Line Harmonics Filter can be found in the
section "Line Harmonics Filter LHF". Here only the harmonic effects on the supply system with Line Harmonics Filters
are discussed in detail.
SINAMICS Engineering Manual – May 2008
42/396
© Siemens AG
100
90
80
70
60
50
40
30
20
10
0
1 3 5 7 9 11 13 15 17 19 21 23 25
Typical current harmonic spectrum with Smart Infeed in
regenerative operation with a line reactor of 4 %
(specified in %)
Typical line current with Smart Infeed in regenerative
operation
th th
and the 7 harmonic in the line current of
= 2 % to be installed in the converter. Further
k