PURPOSE: To control a pulse motor by the simple constitution only of an incremental type position sensor by approximately obtaining the angle of displacement generated between the magnetic poles of a stator and a rotor and acquiring the initial positions of the magnetic poles by using the angle of displacement.
CONSTITUTION: Maximum currents IM are caused to flow through once phase and O[A] through the other phase under the state in which a pulse motor is giver load first. IM/2 is permitted to flow through one phase and O[A] through the other phase without changing load. When the angles of displacement generated in the magnetic poles of a stator 3 and a rotor l in the two cases arc each represented by θ1 and θ2, θ1 and θ2 cannot be measured an incremental type encoder, but the difference of the angle of displacement from the angle of rotation of the rotor can be detected, thus obtaining θ1, then also acquiring a mechanical angle. Accordingly, the initial positions of the magnetic poles are measured, and commutation to the motor is controlled on the basis of detection signals from a position sensor 2.
KUWABARA HAJIME
NIKAIDO MITSUHIRO
MORIMOTO HITOSHI
