ABB ACS880 Series, Firmware Manual

Page: 319 / 764

Def / Type
FbEq 16b / 32b Description Name / Range /
Selection No.
0 ms / real32 Defines the time constant of the speed error low-pass
filter.
If the used speed reference changes rapidly, the
possible interferences in the speed measurement can
be filtered with the speed error filter. Reducing the
ripple with this filter may cause speed controller tuning
problems. A long filter time constant and fast
acceleration time contradict one another. A very long
filter time results in unstable control. Speed error filter
time 24.12
1 = 1 ms / 1 = 1 ms Speed error filtering time constant. 0 = filtering
disabled. 0...10000 ms
Off / uint16 Enables/disables resonance frequency filtering. The
filtering is configured by parameters
24.13 … 24.17 .
The speed error value coming to the speed controller
is filtered by a common 2nd order band-elimination
filter to eliminate the amplification of mechanical
resonance frequencies.
Note: Tuning the resonance frequency filter requires a
basic understanding of frequency filters. Incorrect
tuning can amplify mechanical oscillations and damage
the drive hardware. To ensure the stability of the speed
controller, stop the drive or disable the filtering before
changing the parameter settings.
0 = Resonance frequency filtering disabled.
1 = Resonance frequency filtering enabled.
RFE speed filter 24.13
1 1. On
0 0. Off
45.00 Hz / real32 Defines the zero frequency of the resonance frequency
filter.
The value must be set near the resonance frequency,
which is filtered out before the speed controller.
The drawing shows the frequency response.
20
0
-20
-40
-60
0
50
100 150
f(Hz)
20log
10
|H(ω)|
Frequency of zero 24.14
1 = 1 Hz / 100 = 1 Hz Zero frequency. 0.50 ... 500.00 Hz
Parameters 319