Eddy-currents levitation system

Abstract

Melting metals in a process of electromagnetic levitation is a well-known technique used to avoid the risk of contamination by crucible material as in conventional induction heating systems. A fundamental requirement to achieve a stable levitation melting process relates to the bulk stability of the metallic load, which is the ability of the system to keep the load suspended at a fixed equilibrium position. It is found that the process stability is affected not only by the coil geometry but also by the power supply design. Simulations of a simple series resonant converter as the power supply showed instabilities caused by a phase delay between the sphere movement and the current envelope of the converter.