Design and Development of Fixed-Off Time based Flyback Converter

A novel design topology of the fixed-OFF time-based 30-watt flyback converter is proposed in this paper. This newly proposed converter having lesser component count and isolated outputs is appropriate to charge small batteries, for use in LED driver circuits, to drive small portable pumps, to run BLDC motors which in turn will serve as a replacement of induction motors in ceiling fans. The complete design of a fixed-off time-based flyback converter is presented in this paper. Analysis of RCD clamping is also discussed in detail. A suitable core of ETD39TH-H 14-Pin is selected for the proposed converter transformer. The performance of fixed off time-based flyback converter with the inclusion of power factor correction unit is justified experimentally on the prototype developed in the lab and parameters are found to be within acceptable limits in accordance with IEC 6100-3-2 standard.