Droop Control (Pr. 286 To Pr. 288) - Mitsubishi Electric FR-B-750 to 75K Instruction Manual

Special operation and frequency control

4.20.3 Droop control (Pr. 286 to Pr. 288)

Setting can be made only for FR-B3 series.
This function is designed to balance the load in proportion to the load torque to provide the speed drooping
characteristic.
This function is effective for balancing the load when using multiple inverters
Parameter
Name
Number
286 Droop gain
287 Droop filter time constant
-100%
Droop compensation frequency
REMARKS
Set the droop gain to about the rated slip of the motor.
Synchronous speed at base frequency - Rated speed
Rated slip =
REMARKS
The maximum value of frequency after droop compensation is either 120Hz or Pr. 1 Maximum frequency , whichever is smaller.
♦ Parameters referred to ♦
Pr. 1 Maximum frequency
238
Initial
Value
0%
0.3s
Frequency
Droop compensation
frequency
0
Amount of torque current after filtering
=
Rated value of torque current
Synchronous speed at base frequency
Refer to page 79
B3 B3 B3
Setting
Range
0 Normal operation
Droop control is valid
0.1% to
Set the drooping amount at the rated torque as a
100%
percentage with respect to the rated motor frequency.
Set the time constant of the filter applied on the torque
0 to 1s
amount current.
(1) Droop control
Droop
· The output frequency is changed according to
gain
the magnitude of torque amount current.
· The maximum droop compensation frequency
is 120Hz.
Torque
100%
Rated motor frequency
×
×
100[%]
Description
×
Droop gain
100