Patent ID: 8310182

Claim:
A linear synchronous motor control method in which current passing through an armature of a linear synchronous motor having a movable element moved by magnetic field generated by the armature, wherein: in a case when a moving speed of the armature is faster than a predetermined speed preliminarily determined within a range in which the movable element is moved in synchronous with movement of the magnetic field generated by the armature by a predetermined sensor-less vector control, the current passing through the armature is controlled by the sensor-less vector control, and in a case when the moving speed of the armature is slower than the predetermined speed, in a d-q coordinate in which a d-axis represents a direction of a flux generated by field and a q-axis represents a phase advanced by π/2 with respect to the d-axis, a d-axis armature current and a q-axis armature current are controlled so that a d-axis electric angle corresponding to a position command is produced, and current passes through the d-axis armature and does not pass through the q-axis armature.