Quattro DC Drive Parameters A1
NOTCH FILTER FRQ
(Notch Filter Center Frequency)
Although originally created for gearless
applications where elevator rope resonance is
sometimes an issue, this filter affects the
torque command output of the speed regulator
and will filter out specific frequencies. By
filtering a specific frequency, the speed
regulator will avoid exciting a mechanical
resonance if one exists at that frequency.
There is attenuation across a range of
frequencies, not just at the set frequency, but
also to a lesser degree. The filter starts
attenuation at frequencies lower than the notch
frequency set point. When the notch
frequency is set to low values (less than 10
Hz), the filter can interfere with the desired
response of the drive. This can be exhibited
by minor increase in the rollback of the drive at
start and some deterioration in the ability of the
drive to track an s-curve reference. Generally,
this would not be an issue if the notch
frequency were set at or above 10 Hz.
Notch Filter Example settings:
NOTCH FILTER FRQ (A1) = 20Hz
NOTCH FILT DEPTH (A1) = 50% and 100%
110 100
-30
-25
-20
-10
-5
0
Frequency
(Hz)
A
ttenuation
(dB) -15
38