Siemens SINUMERIK Series Function Manual page 745

This feedforward control mode can be further optimized for a more secure symmetrization
process by changing the axis-specific machine data:
Machine data
MD32810 EQUIV_SPEEDCTRL_TIME
MD37200 COUPLE_POS_TOL_COURSE
MD37210 COUPLE_POS_TOL_FINE
MD37220 COUPLE_VELO_TOL_COURSE
MD37220 COUPLE_VELO_TOL_FINE
In such cases, higher threshold values for the synchronism signals and larger position and/or
speed tolerances result in more stable results.
Dynamic response adaptation
To obtain a good control behavior, FS and LS must have the same dynamic response. The
following error for FS and LS must be equal at any given speed. For dynamically different
spindles, a matching via the dynamic response adaptation can be achieved in the setpoint
branch. The difference of the equivalent time constants between the dynamic "weakest"
spindle to the associated other spindle must be entered as time constant of the dynamic
response adaptation.
Example
When the speed feedforward control is active, the dynamic response is primarily determined
by the equivalent time constant of the "slowest" speed control loop.
● Equivalent time constant LS: MD32810 $MA_EQUIV_SPEEDCTRL_TIME[<LS>] = 5 ms
● Equivalent time constant FS: MD32810 $MA_EQUIV_SPEEDCTRL_TIME[<FS>] = 3 ms
● Time constant of dynamic response adaptation for FS: MD32910
● Activation of the dynamic response adaptation for FS: MD32900
The following error for FS and LS is identical for correctly set dynamic response adaptation:
Operating area "Diagnostics" > "Service axes"
For the optimization, it may be necessary to adjust servo gain factors or feedforward control
parameters slightly.
Position control parameter sets
In the case of spindles, each gear stage is assigned a position-control parameter set. These
parameter sets can be used to adapt the dynamic response for LS and FS in synchronous
operation. This requires that a different gear stage is used for speed and positioning
operation and synchronous operation. The associated gear stage must be switched before
activating the associated operating mode.
Extended Functions
Function Manual, 03/2013, 6FC5397-1BP40-3BA1
$MA_DYN_MATCH_TIME[<FS>] = 5 ms - 3 ms = 2 ms
$MA_DYN_MATCH_ENABLE[<FS>] = 1
S3: Synchronous spindle
Meaning
Equivalent time constant speed control loop for
feedforward control
Threshold value for "Coarse synchronism"
Threshold value for "Fine synchronism"
Velocity tolerance 'coarse'
Velocity tolerance 'fine'
13.4 Points to note
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