Position Control With Proportional-Plus-Integral-Action Controller - Siemens SINUMERIK 840D Function Manual

G2: Velocities, setpoint / actual value systems, closed-loop control
2.6 Optimization of the control
An input value "100%" means: A supplementary torque in accordance with SINAMICS
parameter p2003 is applied when the determined position difference between the two
measuring systems reaches the following value:
● With linear motors: 1 mm
● With linear axis with rotary motor: MD31030 $MA_LEADSCREW_PITCH (leadscrew pitch)
● For rotary axis/spindle: 360 degrees
Standard setting is 0. In this case, the injection of positional deviation is inactive.
Note
The weighting factor MD32950 $MA_POSCTRL_DAMPING can be set on the basis of step
responses, for example.
If the control approaches the stability limit (vibration inclination increases), the parameter is too
large or the value has the incorrect sign.
2.6.4

Position control with proportional-plus-integral-action controller

Function
As standard, the core of the position controller is a P controller. It is possible to switch-in an
integral component for special applications (such as an electronic gear). The resulting
proportional-plus-integral-action controller then corrects the error between setpoint and actual
positions down to zero in a finite, settable time period when the appropriate machine data is set
accordingly.
Overshootings of the actual position for activated PI controller
In this instance, you must decide whether this effect is admissible for the application in
question. Knowledge of the control technology and measurements with servo trace are an
absolute prerequisite for using the function. If the appropriate machine data is incorrectly set,
then machines could be damaged due to instability.
84
CAUTION
Axes and spindles
Function Manual, 06/2019, A5E47437747B AA