Information On Line-Side Harmonics Produced By Converter Units In A Fully-Controlled Two- Pulse Bridge Circuit Configuration (B6C And (B6)A(B6)C) - Siemens SINAMICS DCM Operating Instructions Manual

Connecting
6.1 Instructions for EMC-compliant drive installation
6.1.5 Information on line-side harmonics produced by converter units in a fully-
controlled two-pulse bridge circuit configuration (B6C and (B6)A(B6)C)
The majority of converter units for medium-power applications have a fully-controlled two-
pulse bridge circuit configuration. Below is an example of the harmonics that can be found in
a typical system configuration for two firing angles (α = 20° and α = 60°).
The values have been taken from a previous publication, "Oberschwingungen im
netzseitigen Strom sechspulsiger netzgeführter Stromrichter (Harmonics in the Line-Side
Current of Six-Pulse, Line-Commutated Converters)" by H. Arremann and G. Möltgen,
Siemens Research and Development Division, Volume 7 (1978) No. 2, Springer-Verlag
1978.
In addition, the example specifies formulae which, depending on the actual operating data in
use [line voltage (no-load voltage U
calculate the short-circuit power S
specified harmonics spectrum applies. If the actual line short-circuit power and/or actual
armature inductance deviate from the values calculated in this way, then they will need to be
calculated on a case-by-case basis.
The harmonics spectrum listed below is produced if the values for the short-circuit power S
at the unit terminal and the armature inductance L
formulae below, match the actual values found in the system. If the values do not match, a
separate calculation procedure will need to be carried out for the harmonics.
a) α = 20°
Fundamental factor g = 0.962
ν
5
7
11
13
17
19
23
25
The fundamental component of current I
following formula:
I = g × 0.817 × I
1
where I
and where g is the fundamental factor (see above)
The harmonics currents calculated on the basis of the tables above only apply to
98
I /I ν I
ν 1 ν
0.235 29 0.018
0.100
31 0.016
0.083 35 0.011
0.056 37 0.010
0.046 41 0.006
0.035 43 0.006
0.028 47 0.003
0.024 49 0.003
d
is the DC current of the operating point under investigation
d
), line frequency f
v0
and armature inductance L
K
a
b) α = 60°
Fundamental factor g = 0.953
/I ν
1
5
7
11
13
17
19
23
25
as a reference variable is calculated using the
1
Operating Instructions, 1.2012, C98130-A7066-A1-05-7619
, and DC current I
N d
for the motor to which the
a
of the motor, calculated using the
I /I ν I
ν 1
0.283
29 0.026
0.050 31 0.019
0.089 35 0.020
0.038 37 0.016
0.050 41 0.016
0.029 43 0.013
0.034 47 0.013
0.023 49
0.011
SINAMICS DCM DC Converter
], can be used to
K
/I
ν 1