METHOD FOR LEVITATION CONTROL OF A LINEAR MOTOR, METHOD FOR DETERMINING A POSITION OF A LINEAR MOTOR, INDUCTIVE SENSING DEVICE, AND ELEVATOR SYSTEM

摘要

A method for levitation control of a linear motor (10) comprises the steps:- supplying an alternating current or alternating voltage to at least one oscillating circuit comprising at least one sensing coil being or assumed to be arranged in a fixed spatial correlation to a mover part (11) of the linear motor (10) such that an opening plane of the sensing coil faces a sensor counter-surface of a stator part (12) of the linear motor (10) with a gap therebetween;- receiving a response signal from the oscillating circuit;- determining a gap length of the gap based on the response signal; and- controlling the gap length by driving a magnetic levitation unit (16) of the linear motor (10) based on the determined gap length.;The invention also relates to an inductive sensing device (19) and an elevator system, and a method for determining a position of the linear motor (10).