Mitsubishi Electric fr-e700 series, Инструкция по эксплуатации

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Parameter Special operation
FR-E700 SC EC/ENE 6 - 313
6.20.3 Droop control (Pr. 286 to Pr. 287)
This function is designed to balance the load in proportion to the load torque to provide the speed
drooping characteristic under advanced magnetic flux vector control. This function is effective for
balancing the load when using multiple inverters.
The output frequency is changed according to the magnitude of torque current under advanced
magnetic flux vector control. The drooping amount at the rated torque is set by the droop gain as a
percentage using the rated frequency as a reference.
The maximum droop compensation frequency is 120 Hz.
Pr. No. Name Initial Value Setting Range Description Parameters referred to
Refer to
Section
286
Droop gain 0%
0
Droop control is invalid
(Normal operation) 1 Maximum frequency
PID control
6.4.1
6.20.1
0.1–100%
Droop control is valid
Drooping amount at the rated torque as a
percentage with respect to the rated
motor frequency.
287
Droop filter time constant 0.3 s 0–1 s
Time constant of the filter applied on the
torque current.
I001627E
Fig. 6-162: Droop control
NOTES Set the droop gain to about the rated slip of the motor.
Droop control is invalid during PID control operation.
The maximum value of frequency after droop compensation is either 120 Hz or Pr. 1 "Maximum
frequency", whichever is smaller.
AD MFVC AD MFVC AD MFVC
R
at
ed fr
equenc
y
0 100% 100%
Frequency
command
Droop compensation
frequency
Droop
gain
Torque
Droop compensation frequency
Torque current after filtering
Rated value of base frequency
---------------------------------------------------------------------------------
Rated motor frequency Droop gain
100
--------------------------------------------------------------------------------------------------- =
Rated slip
Synchronous speed at base frequency Rated speed –
Synchronous speed at base frequency
----------------------------------------------------------------------------------------------------------------------------------------------- 100 [%] =