Stability of a levitation melting system fed by an ideal series resonant converter

Electromagnetic levitation melting process is occasionally employed in the metallurgical industry to melt metals in a sterile environment without the risk of specimen contamination by crucible materials. The stability of this process is affected by the system geometry, the construction materials and the power supply design. This paper presents a new analytical stability analysis model of a levitation-melting system fed by an ideal series resonant converter working with a constant switching frequency. It is found that a response delay, of the current envelope signal in the coil, to changes in specimen position has an impact on the system stability. Simulation results validate the developed analytical model.