Low-Pass Filter Time Constant; Use Notch Filter To Suppress Resonance; Use Low-Pass Filter To Suppress Resonance - Delta Electronics ASDA-B Series User Manual

Chapter 6 Control Modes of Operation|ASDA-B Series

Low-pass Filter Time Constant

P2 - 25 NLP
(Resonance Suppression)
Default: 20
Applicable Control Mode: P/S/T
Unit: 0.1ms
Range: 0 ~ 10000
Settings:
This parameter is used to set low-pass filter time constant of resonance suppression.
0: Disabled

Use Notch Filter to suppress resonance

Gain
Resonance
Frequency
.

Use Low-pass Filter to suppress resonance

Gain
Resonance
Frequency
When the low-pass filter (parameter P2-25) is adjusted from 0 to high value, the value of Low-pass
frequency will become smaller (see the figures above). The resonant condition is improved but the
frequency response and phase margin will also decrease and the system may become unstable.
Therefore, if the users know the resonance frequency, the users can eliminate the resonance conditions
directly by using notch filter (parameter P2-23, P2-24). Usually, if the resonant frequency can be
recognized, we recommend the users can directly use notch filter (parameter P2-23, P2-24) to eliminate
the resonance. However, if the resonant frequency will drift or drift out of the notch filter range, we
recommend the users not to use notch filter and use low-pass filter to improve resonant conditions.
6-24
Resonance
Point Gain
0db
Low-pass
Frequency
Frequency
Resonance
Gain
Point
Attenuation
Rate -3db
0db
Low-pass
Frequency
Frequency
Notch Filter
Attenuation
Rate P2-24
Resonance Frequency
Frequency
P2-23
.
Low-pass Filter
Cut-off Frequency
of Low-pass Filter
-
= 10000 / P2-25 Hz
Frequency
Communication Addr.: 0219H
Related Section:
Section 6.3.7, P2-32
Resonance
conditions
Gain
is suppressed
Resonance
Frequency .
Resonance
conditions
Gain
is suppressed
Low-pass
Frequency
Resonance
.
Frequency
Revision January, 2009
Low-pass
Frequency
Frequency
Frequency