Siemens SINUMERIK 840D Function Manual page 376

B2: Acceleration and jerk
12.2 Functions
Since a vibration-capable filter setting is not expected to yield useful results in any case, as with
the "2nd-order filter" (PT2) low-pass filter (PT2) mode of the jerk filter there is no setting option
for the denominator damping D
The band-stop filter can be parameterized in two different ways:
● Real band-stop filter
● Band-stop filter with additional amplitude response increase/decrease at high frequencies
Real band-stop filter
A real band-stop filter is obtained when identical numerator and denominator natural
frequencies are selected:
f = f
N
If the numerator damping setting = 0 is selected, the blocking frequency is equivalent to
complete attenuation. In this case the 3 dB bandwidth is calculated as follows:
f
3 dB bandwidth
If instead of complete attenuation, a reduction by a factor of k is all that is required, then
numerator damping should be selected in accordance with k. In this case the above formula for
calculating the 3 dB bandwidth no longer applies.
Band-stop filter with additional amplitude response increase/decrease at high frequencies
In this case, the numerator and denominator natural frequencies are set to different values. The
numerator natural frequency determines the blocking frequency.
By selecting a lower/higher denominator natural frequency than the numerator natural
frequency, you can increase/decrease the amplitude response at high frequencies. An
amplitude response increase at high frequencies can be justified in most cases, as the
controlled system generally has a lowpass characteristic itself, i.e. the amplitude response
decreases at high frequencies anyway.
Boundary conditions
If the numerator natural frequency is selected to be too high, then the filter is deactivated. In this
case, the frequency limit f
Filter type: Double moving average calculation
Double moving average calculation has a stronger smoothing effect than basic moving average
calculation. By additionally parameterizing a second moving average calculation, differences
in the dynamic response between axes that are interpolating with one another can be
compensated.
376
= f (blocking frequency)
D block
= 2 * f
block
Zmax
. The denominator damping D
D
depends on the position controller clock cycle:
is permanently set to 1.
D
Axes and spindles
Function Manual, 06/2019, A5E47437747B AA