TPF
Total Power Factor λ
6.
Calculate mains-side phase current
3-phase:
1-phase:
I
LN
Mains-side phase current in [A]
S
LN
Mains connected load [VA]
U
LN
Voltage between phases of mains [V]
7.
Select mains contactor
8.
Determine mains circuit breaker and line cross section
See
chapter 15.3.5 "Dimensioning the Line Cross Sections and Fuses "
15.2.2
Calculating the Inrush Current
For calculating the inrush current, take all devices connected to mains volt‐
age into account. The resulting inrush current is the sum of the inrush cur‐
rents of the individual devices.
For the data of the inrush current I
L_trans_max_on
, see Project Planning Man‐
ual "Rexroth IndraDrive Supply Units and Power Sections" → Chapter of the
respective device → "Technical Data" → "Basic Data" → table "Data for Mains
Voltage Supply".
Duration of Inrush Current
For components with resistance charge, the inrush current profile is accord‐
ing to an exponential function. After the delay t
d
is over, the charging process
is completed.
Data for calculating the delay t
d
: See
chapter 15.4.1 "Charging the DC Bus"
15.2.3
Calculations for the Mains Harmonics
Harmonic Load THD
The harmonic load of the mains is described by the THD (total harmonic dis‐
tortion):
I
n
Harmonic current of the n-th harmonic
I
1
rms value of the 1st harmonic (fundamental wave)
I
2
rms value of the 2nd harmonic
I
n
rms value of the n-th harmonic
Fig.15-33:
THD (Total Harmonic Distortion)
Harmonic Content / Distortion Factor k
The harmonic content of, for example, the mains current is described by the
distortion factor k. The distortion factor contains all alternating components,
both those of the fundamental wave (I
1
) and of the harmonics (I
k
). Direct com‐
ponents (I
0
) are not contained.
DOK-INDRV*-SYSTEM*****-PR06-EN-P
Rexroth IndraDrive Drive Systems with HMV01/02 HMS01/02, HMD01, HCS02/03
Bosch Rexroth AG
261/309
Calculations
