Current-Source Type ZVS-PFM DC-DC Power Converter with High-Frequency High-Voltage Transformer for Magnetron Drive and Its Performance Evaluations

Abstract

We have considered a voltage-source type series-resonant ZCS-PFM DC-DC Converter in order to drive an industrial-use magnetron for generating high power microwave in advance. This DC-DC converter can achieve a complete zero current soft switching by assist of the transformer parasitic parameter and a lossless inductive snubber. And the output power is regulated over all power ranges without audible frequency range due to the magnetizing current of the high-frequency transformer. However, this DC-DC converter has a weak point that it is easy to oscillate by the parasitic capacitance of the switching device and the lossless inductive snubber. Therefore in this paper, the new topology that can solve that weak point without hurting good characteristics of that converter is proposed and evaluated on the basis of simulation and experimental results.