Development and Comparison of Industry Available Flyback Topologies

This paper introduces an application space of Power over Ethernet to Universal Serial Bus (USB) Power Delivery, and develops 3 different flyback approaches to a 45 Watt solution in the space. The designs of Fixed Frequency Flyback, Quasi-Resonant Flyback, and Active Clamp Flyback are developed for the application with 37 Volts (V) to 57 V Direct Current (DC) input voltage and 5 V, 9 V, 15 V, and 20 V output, and results are examined for the given specifications. Implementation based concerns are addressed for each topology during the design process. The systems are proven and tested for efficiency, thermals, and output voltage ripple across the operation range. The topologies are then compared for a cost and benefit analysis and their highlights are identified to showcase each systems prowess.