CONTROL METHOD AND DEVICE FOR MOTOR IN POSITION SENSORLESS

摘要

PURPOSE: To provide a control device for motor in position sensorless having a means capable of estimating the accurate position of a rotor even if the estimation of the position of the rotor is difficult when a magnetic saturation locally occurs by a large current. CONSTITUTION: The control device is provided with an AC motor 2 having saliency, a PWM (pulse width modulation) inverter 3 that applies a voltage to the AV motor 2, and a controller 1 that controls the PWM inverter 3 by a PWM signal. The controller 1 is provided with a position estimation means 11 that detects motor inductance in a prescribed direction relative to the direction of a current vector flowing to the AC motor 2, and estimates the position of the rotor of the AC motor based on the motor inductance.