Mitsubishi Electric FR-A820-00046 (0.4K), Instruction Manual

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Parameters Control method
FR-A800 5 - 55
Real sensorless vector control
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The motor speed estimation enables the speed control and the torque control to control currents
more accurately. When a high-accuracy, fast-response control is needed, select Real sensorless
vector control, and perform offline auto tuning.
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This control method can be applied for the following purposes:
– To minimize the speed fluctuation even at a severe load fluctuation
– To generate a low speed torque
– To prevent machine from damage due to a too large torque (torque limit)
– To perform the torque control
NOTE The Real sensorless 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.
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For the motor capacity, the rated current should be equal to or less than the inverter rated cur-
rent. (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 cur-
rent.
●
Offline auto tuning is performed.
Offline auto tuning is necessary under Real sensorless vector control even when the Mitsubishi
motor is used.
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Single-motor operation (one motor to one inverter) is performed.
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A surge voltage suppression filter (FR-ASF/FR-BMF) or sine wave filter (MT-BSL/BSC) is not used.