KEB COMBIVERT F5 Reference Manual page 184

LC - Control Setting Parameters
Proportional Gain
The proportional gain maintains general control and stability over the
i
entire speed range. The proportional gain is split into three values: one
for acceleration and constant speed, (LC03), one for deceleration and
leveling (LC04) and one for pre-torque (LC05). Additionally, the value
can be made speed dependent to automatically increase/reduce (LC25)
with speed. Adjustments are also available for resonant frequencies
(LC20-24).
When control mode is selected for open loop vector (LC01 Control Mode =
(1); Open Loop Vector), these gains will be reduced to a very low setting. It is
recommended not to change the value for proportional or integral gains after
open loop vector has been selected. If closed loop is selected again (LC01
Control Mode = (2) Closed Loop FOC), the gain values will need to be raised
again (Proportional = 3,000 and Integral = 250).
Lower values (less than 1000) may result in loose control and overshoot of
the command speed as high speed is reached. High values can cause high
frequency oscillation resulting in vibration or a buzzing sound in the motor. If
tighter control is necessary, the corresponding proportional gain can be raised
accordingly.
Proportional Gain Too Low (500) - Poor Control
Proportional Gain Low at High Speed (1000) - High Speed Overshoot
Proportional Gain Too High (10,000) - Vibration/Noise
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