Lenze DSD - Manual (Page 325)

Lenze · Drive Solution Designer · Manual · DMS 4.2 EN · 12/2013 · TD23
325
11 Drive Dimensioning
11.2 Motor selection
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Notes on closed-loop speed-controlled winding drives
The following requirements tend to cause unstable behaviour of the drive system control mode:
• Winding drive with high acceleration component in the torque
• Intermittent winding operation (frequent change of torque) with the unwinder or un/rewinder.
The critical value for k
J
is significantly smaller than with a drive without change of torque.
The following measures support stable behaviour of the drive system control mode:
• Precise speed and torque feedforward control
• Keep the influence of the dancer weak
• Adaptation filter time constant - actual speed value
• Adaptation of speed controller gain to variable winder mass
• Jerk limitation of the line speed (S curve)
• Low-backlash mechanical transmission elements with good damping features between the
motor shaft and the winding shaft (e.g. toothed belts or direct drive)
Reels are able to take in very much material, they reach great masses and high moments of inertia.
Hence, a load-matching factor k
J
of up to 5000 may be the result for the drive system.
• For closed-loop speed-controlled winding control modes, DSD generates a message if the load-
matching factor k
J
exceeds a value of 500. The message is provided in the dimensioning proto-
col.
• It is up to the user to assess the impact that a high load-matching factor has on the drive system
and which measures are to be taken if necessary.
11.2.9 Radial forces/axial forces
Dependent on the mechanical construction, radial and axial forces can act on the motor shaft or
driven shaft of the gearbox. Loads due to these forces are not checked in DSD and must be checked
manually.
See also:  Radial and axial loads of the motor or gearbox shaft ( 430)

Note!
Do not use mechanical transmission elements with backlash to ensure a good winding
performance.
• Mechanical transmission elements with backlash (e.g. toothed gearboxes, chains,
cardan shafts, winding shaft intakes) may cause unstable behaviour of the control
mode, even if the k
J
values are small.