Analysis and Design of a High-Frequency Isolated Dual-Tank $LCL$ Resonant AC–DC Converter

An integrated single-phase single-stage high-frequency transformer isolated dual-tank LCL-type series resonant ac-dc converter with fixed-frequency phase-shift control strategy is presented. The circuit configuration combines a diode rectifier, a boost converter, and two identical half-bridge dc-dc LCL resonant converters. A high power factor and a low total harmonic distortion are achieved by discontinuous current mode operation of the front-end power factor correction circuit. The output voltage is regulated by the fixed-frequency phase-shift between two identical half-bridge LCL resonant converters. Soft-switching operation is achieved for all of the switches. The operation of intervals and steady-state analysis are presented briefly. A design example of a 100-W proposed converter is given, together with its simulated and experimental results for different input voltages.