Speed setpoint deceleration
With absolutely correct precontrol, the drive would follow exactly the setpoint even
without speed controller.
The speed measurement however causes also a deceleration of the actual speed
value (scan time ec26, PT1-time ec27). The speed controller wants to control the
decelerated actual speed equal to the speed setpoint and accelerates faster than
required.
Figure 106: Overshoots in the speed setpoint
To avoid this effect, it is reasonable to decelerate the setpoint speed for the speed
controller as well as the actual speed (Filter time + controller reciprocal of amplifi-
cation time).
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