A full-bridge zero-voltage-switched multi-resonant converter for pulse-load applications

The zero-voltage-switching multiresonant technique was used to fabricate a full-bridge converter for high-power, pulse-load applications. The complex operation of the full-bridge zero-voltage switched multiresonant converter is analyzed. The converter can operate in four modes, each representing a specific topological sequence. The DC voltage conversion-ratio characteristics encompassing all possible operating modes are derived. These characteristics are used to define a complete, step-by-step design procedure which minimizes the conduction loss in the primary side of the power stage by minimizing the RMS currents through the switches. The design procedure was used to fabricate a converter that operates at an input voltage of from 220 to 350 V and delivers 32 V to pulse load, with a peak current of 45 A. The maximum efficiency of the converter was measured at 90.5%.<>