Electrical data basic units
Instruction handbook
b maXX
BM4400, BM4600, BM4700
Document No.: 5.12008.07
Baumüller Nürnberg GmbH
78
3.4
12)
The range of the output frequency is based on a stationary operation in the linear range of the PWM, i. e. without overmodulation.
The quality of the generated output voltages depends on the ratio between output frequency and current controller frequency f
I-R
( f
I-R
= 1/cycle time current controller).
The maximum output frequency f
max
, generated with high quality, is calculated as follows:
f
max
f
I-R
K
pf
--------
, typical K
Pf
18
=
Furthermore the controller sets an upper limit for the output frequency of 599 Hz (please contact the responsible Baumüller sales de-
partment, keyword: export restriction).
The range of the output frequency is defined as follows:
PWM frequency
Current controller cycle time
Range of the output frequency
2 kHz
250 µs
0 - 225 Hz
4 kHz/8 kHz
125 µs
0 - 450 Hz
The controller allows the device to generate output voltages with frequencies between f
max
and 599 Hz. However the quality of this volt-
ages cannot be guaranteed.
Typical the devices are marked with the max output frequency at 4 kHz switching frequency: 0 ... 450 kHz.
13)
With an output frequency lower than 0.5 Hz, the output current may be 80 % at maximum of the rated output current.
14)
The continuously permitted output current must be reduced complying with
Output frequency dependent continuous current derating
on page 112, if the statical output frequency is lower than 15 Hz and the frequency remains between 0 and 15 Hz for over
5 seconds.
Summary of Contents for b maxx BM4400
Page 359: ......
