Kollmorgen AKD PDMM series, User Manual

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AKD PDMM User Guide | 48.1 VL.ARPF1 TO VL.ARPF4
48.1 VL.ARPF1 TO VL.ARPF4
General Information
Type R/W Parameter
Description
Sets the natural frequency of the pole (denominator) of anti-resonance (AR)
filters 1, 2, 3, and 4; active in opmodes 1 (velocity) and 2 (position) only.
Units Hz
Range 5 to 5,000 Hz
Default
Value
500 Hz
Data Type Float
See Also
VL.ARPQ1 TO VL.ARPQ4 (pg 451), VL.ARZF1 TO VL.ARZF4 (pg 452), Sets
the Q of the zero (numerator) of anti-resonance filter #1; active in opmodes 1
(velocity) and 2 (position) only. (pg 453)
Start Ver-
sion
M_01-02-00-000
Fieldbus Index/Subindex Object Start Version
EtherCAT COE and CANopen
3406h/1 VL.ARPF1
M_01-02-00-000
3406h/2 VL.ARPF2
3406h/3 VL.ARPF3
3406h/4 VL.ARPF4
Description
VL.ARPF1 sets the natural frequency of the pole (denominator) of AR filter 1. This value is F
P
in the approximate transfer function of the filter:
ARx(
s
) = [
s
²/(2πF
Z
)² +
s
/(Q
Z
2πF
Z
) + 1]/ [
s
²/(2πF
P
)² +
s
/(Q
P
2πF
P
) + 1]
The following block diagram describes the AR filter function; note that AR1 and AR2 are in the
forward path, while AR3 and AR4 are applied to feedback:
AR1, AR2, AR3, and AR4 are used in velocity and position mode, but are disabled in torque
mode.
Discrete time transfer function (applies to all AR filters)
The velocity loop compensation is actually implemented as a digital discrete time system func-
tion on the DSP. The continuous time transfer function is converted to the discrete time domain
by a backward Euler mapping:
s ≈ (1-z
-1
)/t, where t = 62.5 µs
The poles are prewarped to F
P
and the zeros are prewarped to F
Z
.
Related Topics
1 Velocity Loop
450 Kollmorgen™ | December 2012