Speed Smoothing Control - Mitsubishi Electric FR-F820-00077 Instruction Manual

Parameters
5.13.14

Speed smoothing control

There are times where the vibration due to mechanical resonance affect the inverter, making the out-
put current (torque) unstable. In such case, vibration can be decreased by reducing the deviation in
the output current (torque) by changing the output frequency.
Pr.
653
G410
654
G411
Control block diagram
Speed
command
Fig. 5-278:
Setting method
● When vibration caused by mechanical resonance occurs, set Pr. 653 "Speed smoothing control"
to 100%, and operate at the operation frequency with largest vibration, and confirm if the
vibration is suppressed after few seconds.
● If there is no effect, gradually raise the setting value of Pr. 653, perform the operation and
confirmation of the effect repeatedly, and use the value (Pr. 653) with most effect as the final
setting value.
● If the vibration gets larger by raising Pr. 653, lower the value of Pr. 653 under 100%, and perform
the confirmation of result in a same manner.
● When the vibration frequency (frequency of torque deviation, speed deviation, or converter
output voltage deviation) by the mechanical resonance with a measurement device, etc., set the
frequency of 1/2 to 1 times the vibration frequency in Pr. 654 "Speed smoothing cutoff frequency".
(Setting vibrational frequency range can suppress the vibration better.)
Current for
torque
NOTE Depending on the equipment, the vibration may not be suppressed sufficiently or the effect is not
obtained.
FR-F800
Name
Speed smoothing control
Speed smoothing cutoff
frequency
Acceleration/deceleration
processing
Output frequency
+
Control block diagram
Cutoff frequency
Torque fluctuation
detection range
0
159 Hz (fixed)
Pr. 654
V/F V/F V/F Magnetic flux Magnetic flux Magnetic flux
Initial Setting
Description
value range
Confirm the effect by raising and lowering the value
0% 0 to 200%
with 100% as a reference.
Set the lower limit of the torque deviation cycle
20 Hz 0 to 120 Hz
(frequency).
V/F control
-
Speed smoothing control
Cutoff frequency
Pr. 654
Proportional gain
Pr. 653
Fig. 5-279:
Setting method
Vibrational
frequency
(G) Control parameters
Frequency output
Voltage output
Current for torque
I002760E
I002761E
5 - 567