Design considerations for long-range magnetic levitation using reluctance actuators

Abstract

Magnetic levitation is increasingly used in high precision mechatronic motion systems like positioning stages for semiconductor exposure systems. In most magnetic levitation systems the working range in the levitation direction is limited to about 1 mm, and it is desired to increase this range. However, without special means increasing this working range also increases the power consumption, which is undesirable for precision applications mainly due to Joule's Law (P=I²R) heat dissipation. In order to increase the working range of a magnetic levitation system without sacrificing the static and dynamic load capacity, three different coplanar actuator configurations are discussed that enable long-range magnetic levitation.