A Single-Stage Asymmetrical Half-Bridge Flyback Converter with Resonant Operation -Chung-Yi Ting , Yi-Chieh Hsu -Department of Electronic and Computer Engineering, National Taiwan University of Science and Technology

A Single-Stage Asymmetrical Half-Bridge Flyback Converter with Resonant Operation Chung-Yi Ting , Yi-Chieh Hsu , Jing-Yuan Lin ,and Chung-Ping Chen Department of Electronic and Computer Engineering, National Taiwan University of Science and Technology.

 Abstract: This paper proposes a single-stage asymmetrical half-bridge fly-back (AHBF) converter with resonant mode using dual-mode control. The presented converter has an integrated boost converter and asymmetrical half-bridge fly-back converter and operates in resonant mode. The boost-cell always operates in discontinuous conduction mode (DCM) to achieve high power factor. The presented converter operates simultaneously using a variable-frequency-controller (VFC) and pulse-width-modulation (PWM) controller. Unlike the conventional single-stage design, the intermediate bus voltage of this controller can be regulated depending on the main power switch duty ratio. The asymmetrical half-bridge fly-back converter utilizes a variable switching frequency controller to achieve the output voltage regulation. The asymmetrical half-bridge fly-back converter can achieve zero-voltage-switching (ZVS) operation and significantly reduce the switching losses. Detailed analysis and design of this single-stage asymmetrical half-bridge fly-back converter with resonant mode is described. A wide AC input voltage ranging from 90 to 264 Vrms and output 19 V/ 120 W prototype converter was built to verify the theoretical analysis and performance of the presented converter.
Keywords: fly-back converter; zero-voltage-switching (ZVS); Variable-frequency-controller (VFC); single-stage
LINK:  https://www.preprints.org/manuscript/201805.0140/v1