Kruger Ecowatt K320 Series Operation Manual page 70

Ecowatt Drive K320 series
®
The VFD provides dedicated function codes for the space voltage control mode. You can
improve the space voltage control performance by means of setting.
Torque boost
(1)
The torque boost function can effectively compensate for the low-speed torque performance in
space voltage control. Automatic torque boost has been set by default, which enables the VFD
to adjust the torque boost value based on actual load conditions.
Note:
Torque boost takes effect only at the torque boost cut-off frequency.

If torque boost is too large, the motor may encounter low-frequency vibration or

overcurrent. If such a situation occurs, reduce the torque boost value.
Energy-saving run
(2)
During actual running, the VFD can search for the max. efficiency point to keep running in the
most efficient state to save energy.
Note:
This function is generally used in light load or no-load cases.

This function is no applicable to the cases where sudden load changes often occur.

V/F slip compensation gain
(3)
Space voltage vector control belongs to an open-loop mode. Sudden motor load changes cause
motor speed fluctuation. In cases where strict speed requirements must be met, you can set
the slip compensation gain to compensate for the speed change caused by load fluctuation
through VFD internal output adjustment.
The setting range of slip compensation gain is 0–200%, in which 100% corresponds to the rated
slip frequency.
Note: Rated slip frequency = (Rated synchronous rotation speed of motor – Rated rotation
speed of motor) x (Number of motor pole pairs)/60
Output voltage V
boost
cut-off
Output frequency f
-61-
Basic operation guidelines