Mitsubishi Electric FR-A800, Instruction Manual

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Parameters Control method
FR-A800 5 - 49
5.2 Control method
V/F control (initial setting), Advanced magnetic flux vector control, Real sensorless vector control,
vector control, and PM sensorless vector control are available with this inverter.
V/F control
It controls the frequency and voltage so that the ratio of frequency (F) to voltage (V) is constant while
changing the frequency.
Advanced magnetic flux vector control
This control performs vector calculation and divide the inverter's output current into an excitation
current and into a torque current. The frequency and the voltage are then compensated to flow the
motor current that meets the load torque. This control methods improves the torque generation at a
low speed. The output frequency is further compensated (slip compensation) to bring the actual mo-
tor speed closer to the commanded speed. This function is useful when the load fluctuates are large.
.
NOTE Advanced magnetic flux vector control requires the following conditions.
If the conditions are not satisfied, select V/F control. Otherwise, malfunctions such as insufficient
torque, uneven rotation may occur.
●
For the motor capacity, the rated current should be equal to or less than the rated inverter cur-
rent. (It must be 0.4 kW or higher.)
Using a motor with the rated current substantially lower than the rated inverter current will
cause torque ripples, etc. and degrade the speed and torque accuracies. As a reference, select
the motor with the rated motor current that is about 40% or higher of the rated inverter cur-
rent.
●
The motor described in the table below is used.
●
Single-motor operation (one motor to one inverter) is performed.
●
The wiring length from inverter to motor is 30 m or less. (When the wiring length exceeds
30 m, perform offline auto tuning in a wired state.)
●
A sine wave filter (MT-BSL/BSC) is not used.
Motor Condition
Mitsubishi standard motor (SF-JR)
Offline auto tuning is not required
Mitsubishi high-efficiency motor (SF-HR)
Mitsubishi constant-torque motor (SF-JRCA 4P, SF-HRCA)
Mitsubishi high-performance energy-saving motor (SF-PR)
Other motors (other manufacturers, SF-TH, etc.) Offline auto tuning is required