Delta ASDA-B2-F Series User Manual page 110

ASDA-B2-F
Here illustrates the effect via low-pass filter (parameter P2-25). The following figure is the system
open-loop gain with resonance.
Gain
When the value of low-pass filter (parameter P2-25) is increased from 0, BW becomes smaller
(See the following figure). Although it improves the situation of resonance frequency, the
response bandwidth and phase margin are reduced as well.
Gain
0dB
If users know the resonance frequency, notch filter (P2-23 and P2-24) can directly eliminate the
resonance. The frequency setting range of the notch filter is merely from 50 to 1000 Hz. The
suppression strength is from 0 to 32 dB. If the resonance frequency is not within the range, it is
suggested to use low-pass filter (P2-25) to decrease the resonance intensity.
Here firstly illustrates the influence brought by notch filter (P2-23 and P2-24) and low-pass filter
(P2-25). The following figures are the system of open-loop gain with resonance.
Resonance suppression with notch filter:
Gain
Resonance
Frequency
September, 2015
Gain
Resonance Point
0 db
+
Attenuation Rate
B.W
Frequency
BW
Gain
Notch Filter
=
P2-24
Frequency
Resonance
Frequency P2-23
Control Mode of Operation
Frequency
Frequency
Resonance condition is
suppressed
B.W
Frequency
Resonance
Frequency
6
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