Sensorless control is a method for controlling a permanent magnet motor by estimating the rotor position (magnet position) and speed in the drive unit instead of using a sensor (encoder). Speed can be controlled with high precision even without a sensor (encoder) thanks to the PM sensorless vector control equipped with Mitsubishi Electric’s proprietary adaptive magnetic observer (*1).
The adaptive magnetic flux observer scheme is a control method in which a virtual motor model is included within the drive unit and detects the speed and magnetic pole position within the motor based on its voltage and electric current.