Siemens SINUMERIK 840D sl Function Manual page 259

Bandstop 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 possesses a lowpass characteristic itself, i.e., the amplitude
response drops at high frequencies anyway.
Supplementary conditions
If too high a numerator natural frequency is selected, the filter is disabled. In this case the
limiting frequency f
The limitation is enabled for specific axes using machine data:
MD32400 $MA_AX_JERK_ENABLE (axial jerk limitation)
and set with time specifications for the smoothing filter using machine data:
MD32410 $MA_AX_JERK_TIME (time constants for the axial return filter)
.
With SW 5.1 and higher, it is also possible to control the jerk limitation in the position
controller with a new filter based on a smoothing method that incurs few contour errors:
MD32402 AX_JERK_MODE = 1
MD32402 AX_JERK_MODE = 2
MD32402 AX_JERK_MODE = 3
Modus 2 requires a bit more computation time, but with the same smoothing effect, it results
in lower contour errors or, with the same accuracy, in a smoother contour with smoother
movements. Mode 2 is recommended. Mode 1 is the default mode in SW 1 to SW 4.4 for
compatibility reasons.
For more information about how the jerk filter available with SW 5.1 and higher works
(balancing filter for improving the position setpoints of the position controller), please refer to:
References:
/FB1/ Manual of Functions, Basic Functions; Velocities, Setpoint/Actual-Value Systems,
Regulatory Control (G2), Chapter: "Control Optimization"
Mode 3
There are 2 parameterization options for the bandstop filter:
• "Real bandstop filter":
Basic logic functions: Acceleration (B2)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
depends on the position-control cycle:
Zmax
When identical numerator and denominator natural frequencies are selected (=blocking
frequency). If you select (numerator) damping setting zero, the blocking frequency is
equivalent to complete attenuation.
2.17 Jerk filter (axis-specific)
; 2nd-order filter (default)
corresponds to SW 1 to SW 4.4
; Sliding mean value generation
(New jerk filter with SW 5.1 and higher).
; Bandstop filter with SW 6.3 and higher
Functions
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