CHARACTERIZATION OF AN ACTIVE CLAMP FLYBACK TOPOLOGY FOR POWER-FACTORCORRECTION APPLICATIONS

Flyback derived topologies have long been attractive because of their relative simplicity when compared with other topologies used in low-po wer applications. Incorporation of active clamp circuitry provides the additional benefit of recycling transformer leakage energy while mini mizing switch voltage stress. This paper presents the analysis, design , and experimental results of 500 W single stage and 600 W interleaved active clamp flybacks used for power factor correction, Several pract ical issues, including the application of charge control, the use of m ixed power devices, and a solution to the hold-up time problem are dis cussed and experimentally verified.