Lenze 8400 motec - Manual (Page 155)

Lenze · 8400 motec · Reference manual · DMS 4.1 EN · 08/2013 · TD05 155
5 Motor control (MCTRL)
5.10 Parameterisable additional functions
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5.10.5 Oscillation damping
Mechanical oscillations are undesirable effects in every process and they may have an adverse effect
on the single system components and/or the production output.
Mechanical oscillations in the form of speed oscillations are suppressed by the oscillation damping
function.
Oscillation damping is successfully used with
• unloaded motors (no-load oscillations)
• motors whose rated power deviates from the rated power of the controller.
• e.g. during operation at high switching frequency including the power derating involved.
• operation with higher-pole motors
• operation with special motors
• compensation of resonance in the drive
• At an output frequency of approx. 20 ... 40 Hz, some asynchronous motors can show
resonance which causes current and speed variations and thus destabilise the running
operation.

How to eliminate speed oscillations:
1. Approach the area where the speed oscillations occur.
2. Reduce the speed oscillations by changing
C00234 step by step.
3. These can be indicators for smooth running:
• Constant motor current characteristic
• Reduction of the mechanical oscillations in the bearing seat
Related topics:

L_NLim_1 FB: Blocking frequency function ( 446)
Parameter Info Lenze setting
Value Unit
C00234 Oscillation damping influence 5 %
(50 % from 2.2 kW device power)
C00235 Oscillation damping filter time 50 ms