Analysis and design of isolated single-switch converter for magnetron filament heating

Abstract

This paper presents the analysis and design of isolated voltage-fed single-switch soft-switched converter for magnetron filament heating. A step-down transformer is used to obtain the required voltage conversion ratio and isolation. By low-damped resonance, the primary transistor achieves zero-voltage switching. The secondary diode naturally attains zero-current switching due to discontinuous current. An additional inductor is added to the secondary current loop to stabilize the charging current. To verify the analysis and design, a prototype converter is built and tested. The simulation and experimental results coincide with the prediction.