Drive Configuration
Controller Tuning
Additive, Gain
Additive, Time Constant
G
r
(
s
)=
Kd
s
T1 s
+
1
+
Kp
+
Ki
1
s
G
r
(
s
)=
Kr
(
Tv s
T1 s
+
1
+
1
+
1
Tn s
)
Kp
=
Kr ;
Ki
=
Kr
Tn ;
Kd
=
Kr Tv ;
Note
Note
In most cases it is recommended and more intuitive to use
Additive, Time Constant
for the
tuning of the position controller.
With the
Select Filter
panel up to 5 filters can be configured. Use the
Filter Parameter
panel to set the
Type
, frequency
f[Hz]
and damping
D[1]
. To disable the filter, the type is set to
Bypass
. If
Advanced
is
checked, the frequency and damping of the numerator and denominator can be set independent (see
also chapter 5.4.5).
The
Bode
plots show the following complex transfer functions:
G
r
(
f
)
;
G
o
(
f
)=
G
r
(
f
)
H
c
(
f
)
x
i
(
f
)
F
0
(
f
)
F
1
(
f
)
...
F
4
(
f
)
;
G
c
(
f
)=
G
o
(
f
)
1
+
G
o
(
f
)
with
f
: frequency
G
r
(f)
: position controller transfer function
G
o
(f)
: open loop transfer function
G
c
(f)
: closed loop transfer function
H
c
(f)
: closed loop current controller transfer function
x/i(f)
: measured frequency response current to position
F
0
(f)F
1
(f)...F
4
(f)
: filter transfer function
The
Nyquist
plot shows the open loop transfer function
G
o
(f)
in the complex area.
The goal for the tuning of the position controller is to get a stable controller with the following charac-
a) wide bandwidth of
G
c
(f)
b) high amplification in the pass-band of
G
o
(f)
c) sufficient attenuation in the stop-band of
G
o
(f)
(which may require to place some filters)
.
with the following tuning criteria in
Bode
plot view:
d) The phase-margin of
G
o
(f)
should be in range of 30° to 50°.
e) The amplitude of the
G
c
(f)
should not exceed 2dB (robust) to 4 dB (advanced) for a stable con-
troller behavior over the whole frequency range.
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