Function library – Lenze EVS9332xK User Manual
Page 101

Function library
Function blocks
3.2.19
Setpoint conditioning (CCTRL)
3−73
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EDSVS9332K−EXT EN 4.0
3.2.19.4
Speed feedforward control
Via the speed feedforward control the faster control loops are activated earlier. Use this function if
the drive generates a following error (negative or positive) when accelerating.
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Via the input CCTRL−NRED the feedforward control can be decreased or increased
proportionally to the angle setpoint change d
j/dt.
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Values > 100% increase the feedforward control. If the values are too high, the drive leads or
runs unstable in dynamic processes.
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Values < 100% decrease the feedforward control. If the gain is too low, the drives generates a
following error (drive lags) during acceleration or braking (dynamic).
)
Note!
The input value at CCTRL−NRED is processed as an absolute value, i.e. negative
values are interpreted as positive.
3.2.19.5
Torque feedforward control
Via the torque feedforward control the faster (internal) control loops are activated earlier. Use this
function if the drive generates a following error (negative or positive) when accelerating. Where
required, you have to increase the reset time of the n−controller.
(
Stop!
The torque feedforward control has a much more sensitive influence on the drive
than the speed feedforward control.
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The feedforward control can be increased or decreased proportionally to the speed change
dn/dt via the input CCTRL−MRED.
– Values > 100% increase the feedforward control. If the values are too high, the drive leads or
runs unstable in dynamic processes.
– Values < 100% decrease the feedforward control. If the gain is too low, the drives generates
a following error (drive lags) during acceleration or braking (dynamic).
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With codes C1348/1 (numerator) and C1348/2 (denominator), the feedforward control can be
adapted to the inertia of the machine.
)
Note!
The input value at CCTRL−MRED is processed as an absolute value, i.e. negative
values are interpreted as positive.