Mitsubishi Electric 800 Series Instruction Manual page 132

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 motor speed closer to the commanded speed. This function is useful when the load
fluctuates are severe.
POINT POINT
• 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 motor current should be equal to or less than the inverter rated current. (It must be 0.4 kW
or higher.)
Using a motor with the rated current substantially lower than the inverter rated 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 inverter rated current.
• The motor described in the table below is used.
Standard motor
Constant-torque motor
Other motors (other manufacturers' motors)
• Single-motor operation (one motor to one inverter) is preformed.
• 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.)
Motor Condition
Offline auto tuning is not required
Offline auto tuning is required
PARAMETERS
Control method
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