ACSetup programme
Positioning module IMD20, IMD40
Target position
Target speed
option
al
Ground
Actual position
kd
kp
Overtravel limitation
Output= MAX
Actual speed
een the target and the actual position cannot be greater than the following
limitation, since the target position follows the actual position, if this distance is exceeded. A too great
value of an following limitation might lead to a permanent vibration of the axes. For the optimisation
of the following limitation, see “Can Interpolation dialogue box” on page 72.
If the
Limit hard
option is enabled, the controller output is set to its maximum values, when the
following limit is achieved. Otherwise, it has a value corresponding to the deviation.
For the testing of the controller setting, a test signal can be used, too. For this, three rectangular
impulses are defined as target speed (the overall duration and amplitude can be set). The actual
speed can be used to verify the controller setting. New control parameters are transferred only briefly
to the drive module during the test and are then replaced again by the previous parameters. The
parameters can be tested both at standstill as well as in motion.
In the beginning, it is best to use the default values and to only then try different settings.
Some basic setting rules:
y
In case of a strong following, reduce kp and / or increase kd.
y
Too high a D proportion leads to a rough motor operation and to loud noises.
y
An increase of td corresponds to a duplication of the D proportion (half kd).
y
ki should not be greater than kp. Often, very small values suffice.
y
For the setting of the following limitation, a higher target speed should be chosen. The
reduction of the following limitation leads to a reduction of the following and a flattening of the
ramps. Reduce the following limitation up to the point, at which the ramp slope is still as high
as in case of a high following limitation. It might be possible to increase kp further. Then, the
“Limit jard” option can be activated in order to achieve a higher acceleration.
The requirements for the controller can differ considerably from application to application. A smooth
course of the actual speed with a small following (see Figure) e.g. is a good compromise for many
application purposes.
The deviation betw
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