Lenze 8400 - Oscillation Damping Voltage Range

Lenze · 8400 HighLine · Reference manual · DMS 12.0 EN · 06/2017 · TD23 273
5 Motor control (MCTRL)
5.10 Parameterisable additional functions
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5.10.6.1 Oscillation damping voltage range
The oscillation damping voltage range is successfully used with
• unloaded motors (no-load oscillations)
• motors whose rated power deviates from the rated power of the inverter.
• 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 in no-load operation at speeds with 40 ... 80 % of the
rated speed:
1. Approach the area where the speed oscillations occur.
2. Reduce the speed oscillations by changing C00234
step by step (increment 1 %).
• The filter time oscillation damping (C00235
) should not be changed.
3. These can be indicators for smooth running:
• Constant motor current characteristic
• Reduction of the mechanical oscillations in the bearing seat
Parameters Info Lenze setting
Value Unit
C00234 Oscillation damping influence 5.00 %
C00235 Oscillation damping filter time 32 ms
 Note!
Compensate the resonance during operation with feedback (closed loop, feedback of
n
act
) via the parameters of the slip regulator.
Parameterising the slip regulator
( 189)