Optimization Of The Control; Position Controller, Position Setpoint Filter: Balancing Filter - Siemens SINUMERIK 828D Function Manual

G2: Velocities, setpoint / actual value systems, closed-loop control

7.6 Optimization of the control

7.6 Optimization of the control
7.6.1

Position controller, position setpoint filter: Balancing filter

Application
For speed and torque feedforward control
With feedforward control active, the position setpoint is sent through a so­called balancing filter before it reaches
the controller itself. It is thus possible to control the speed setpoint to 100 % in advance, without resulting in
overshoots when positioning.
Filter activation
The filter is activated and the precontrol version selected by changing the axial machine data:
MD32620 $MA_FFW_MODE
Value Meaning
3 Speed precontrol
4 Combined torque/speed precontrol
Activation of feedforward control
Parts programs can be used to activate and deactivate the feedforward control for all axes, using instructions
FFWON and FFWOF, which does not affect the following machine data:
MD32630 FFW_ACTIVATION_MODE
Control response with POWER ON, RESET, REPOS, etc.
In the case of POWER ON and RESET, as well as with "Enable machine data", the setting data of the
feedforward control are read in anew (see the appropriate values of the machine data).
Mode change, block search and repositioning have no influence on the feedforward control.
Recommended setting in case of recommissioning
If recommissioning, or if previous standard values are loaded (switch position 1 on commissioning switch and
POWER ON), the following machine data default values apply:
MD32620 $MA_FFW_MODE = 3
MD32610 $MA_VELO_FFW_WEIGHT = 1
The balancing time for the speed feedforward control then just has to be adjusted in the following machine data:
MD32810 $MA_EQUIV_SPEEDCTRL_TIME
380
Function Manual, 09/2011, 6FC5397-0BP40-2BA0
Basic Functions