SPEED CONTROL METHOD FOR SYNCHRONOUS MOTOR AND CONSTANT IDENTIFYING METHOD

摘要

In a sensor-less vector control which uses a rotation speed and a rotor position of a synchronous motor (6), a true magnetic axis d axis is assumed to exist in a phase deviated a load angle theta e from a gamma axis to supply a positive current to the gamma axis to thereby generate a torque proportional to i gamma sin theta e and oriented in a gamma axis direction at a magnetic axis, whereby an error between a true magnetic axis d-q axis and a control axis gamma - delta axis is eliminated to constantly make a control axis gamma axis match a synchronous motor magnetic axis d axis even under load and effect an excellent vector control.