FFT without filtering
FFT with filtering
Table 7.16: FFT transformation
NOTE
l
Note that the filters not only have an effect on the amount but also
on the phase of the frequency response. At lower frequencies
higher-order filters (PT3, PT4) should not be used, as the phase
within the control bandwidth is negatively influenced.
l
The coefficients can also be specified directly via parameter
P 327
- CON_SCON_FilterPara
. They take effect directly, so changing
them is only recommended when the control is switched off.
l
A large bandwidth will result in a lower attenuation of the cut-off
frequency.
MOOG
ID No.: CB40859-001 Date: 11/2020
MSD Servo Drive - Device Help
137
7 Control
ID
Index Name
Unit
Description
325
CON_SCON_FilterFreq
Filter frequencies of digital filter
325
0
CON_SCON_FilterFreq
Hz
1st center/cutoff
325
1
CON_SCON_FilterFreq
Hz
1st width
325
2
CON_SCON_FilterFreq
Hz
2nd center/cutoff
325
3
CON_SCON_FilterFreq
Hz
2nd width
326
0
CON_SCON_FilterAssi
Digital filter design assistant
327
CON_SCON_FilterPara
Coefficients of digital filter
327
0
FilterPara b0
b0*x(k)
327
1
FilterPara b1
b1*x(k-1)
327
2
FilterPara b2
b2*x(k-2)
327
3
FilterPara b3
b3*x(k-3)
327
4
FilterPara b4
b4*x(k-4)
327
5
FilterPara a1
a1*y(k-1)
327
6
FilterPara a2
a2*y(k-2)
327
7
FilterPara a3
a3*y(k-3)
327
8
FilterPara a4
a4*y(k-4)
1550
0
SCD_NotchType
Adaptive Notch filter: Method
1551
0
SCD_NotchCntl
Adaptive Notch filter: Control word
1552
SCD_NotchFreq
Adaptive Notch filter: Frequencies
1552
0
SCD_NotchFreq
Hz
Adaptive Notch filter: Frequency
1552
1
SCD_NotchLambda
Hz/min^-
2
Adaptive Notch filter: Coefficient
1552
2
SCD_NotchMinFreq
Hz
Adaptive notch filter: Minimum frequency
1552
3
SCD_NotchMaxFreq
Hz
Adaptive notch filter: Maximum frequency
1552
4
SCD_NotchDeltaFreq
Hz
Adaptive Notch filter: Maximum frequency
change (in each iteration)
Table 7.17: “Speed controller - Digital filter” parameter
7.4.3 Analysis of Speed control
The speed controller is executed as a PI controller. The gain (P-component) and the
integral-action time (I-component) of the individual controllers are programmable.
In order to optimize the speed control loop, two rectangular reference steps are
preset. For automatic controller optimization the step response and transfer function
wizards are available.