4 traction-controlled winding drive, 7applications – Lenze DSD User Manual

Page 210

Applications

7.22

Winding drive for rewinder/unwinder

210

Lenze · Drive Solution Designer · Manual · DMS 4.2 EN · 12/2013 · TD23

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7.22.4

Traction-controlled winding drive

In winding drives, the tensile force is generated by the static torque M

stat

. During the acceleration

and deceleration phases, the drive requires an additional dynamic torque M

dyn

In order to prevent the tensile force from exceeding the limit values and in order to avoid empty

reels, the dynamic component of the torque should be smaller than the static component for trac-

tion-controlled winders. If the disturbance compensation works well and is repeatable, the dynamic

component may be a little greater than the static component. Critical phases are accelerations dur-

ing the start of winding to an empty reel with minimum tensile force.

• Guide value: M

dyn

< 1 ... 3 × M

stat



Tip!
How to limit the dynamic torque:

• Select moderate acceleration and deceleration times
• Create an S-shaped motion profile

The M

dyn

stat

ratio can be read from the torque-time characteristic of the motor. Dimension the

drive completely and zoom in on the start of the characteristic (starting time) to be able to see the

dynamic torque. Use the Zoom function for this purpose.

[7-233] Torque-time characteristic of the motor