Delta ASD-A2-0121 Series User Manual page 244

ASDA-A2
Resonance suppression with low-pass filter
Gain
Resonance
Frequency
When the value of P2-25 is increased from 0, BW becomes smaller. Although it solves the problem
of resonance frequency, the response bandwidth and phase margin is reduced. Also, the system
becomes unstable.
If users know the resonance frequency, notch filter (parameters P2-23 and P2-24) can directly
eliminate the resonance. In this case, notch filter will be more helpful than low-pass filter. However,
if the resonance frequency drifts because of time or other factors, notch filter will not do.
Resonance
Gain
Point
Attenuation
Rate -3db
0db
Low-pass
Frequency
Frequency
Chapter 6 Control Mode of Operation
.
Low-pass Filter
Gain
Cut-off Frequency
of Low-pass Filter
-
= 10000 / P2-25 Hz
Frequency
Resonance
conditions
is suppressed
Low-pass
Frequency
Frequency
Resonance
.
Frequency
6-47