Example 2: Reoptimize The Speed Controller Of An Axis - Siemens SINUMERIK 840D sl Function Manual

CYCLE751(4)
CYCLE757(myaxiswithnewload,"ANEWINERTIA.XML",1,,)
CYCLE757(myaxiswithnewload,"ANEWFREQRESP.CSV",3,,)
CYCLE759(myaxiswithnewload,34,,,"_AST_R_ESTINERTIA")
; If necessary, check the optimization results and then activate.
; Do not activate the results.
; Use predefined parameter sets.
CYCLE751(2)
; Switch to the newly optimized DDS or select the predefined DDS depending on the load inertia.
; Limit the acceleration depending on the new inertia.
M30
12.5.2

Example 2: Reoptimize the speed controller of an axis

The controller setting of the rotary axis (here: 4th axis) driven with a torque motor depends on
the clamping equipment and the load inertia. If the clamping equipment or the load inertia
changes, the axis must be measured again. A new controller parameter set must be
determined (a DDS will be overwritten), otherwise the axis would be unstable because of the
new resonances. New current setpoint filters must probably by set. Only the speed controller
is reoptimized. Because the position control remains identical and the precontrol should not
be changed, a similar bandwidth of the speed controller should be attained again. For this
purpose, a target bandwidth can be selected in the speed controller optimization strategy. This
is set to 100 Hz for the "normal compensation" optimization objective. If the new load inertia
and the clamping make many filters necessary and the ratio from the load inertia / motor inertia
is large, this objective may possibly not be achieved. In this case, a message is issued. And
the axis machine data is still set correctly from the first optimization (initial commissioning).
This means that the precontrol mode (MD32620 $MA_FFW_MODE), DSC (MD32640
$MA_STIFFNESS_CONTROL_ENABLE), position controller gain (MD32200
$MA_POSCTRL_GAIN) and equivalent time precontrol (MD32800
$MA_EQUIV_CURRCTRL_TIME or MD32810 $MA_EQUIV_SPEEDCTRL_TIME) are set
correctly so that the loop interpolation is correct.
The results of the reoptimization, such as the complete inertia, can be read with CYCLE759.
The newly optimized speed controller is written to another data set. The path interpolation is
not considered here, because it is assumed that the precontrol data does not change
significantly or another axis has a larger time constant in MD32800
$MA_EQUIV_CURRCTRL_TIME. The optimization strategy for axis and speed controllers
selected from the user interface is deployed and stored in the XML file for this axis (\user
\sinumerik\data\optimization\AST_AX4_A1....xml).
Special functions
Function Manual, 01/2015, 6FC5397-2BP40-5BA2
T4: Automatic retuning with AST - only 840D sl
; Start the optimization without acti-
vating the results.
; Save the optimization data in an XML
file.
; Export the speed-controlled system.
; Fetch the inertia.
; Close the optimization session.
12.5 Examples
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