Dual voltage regulations of single switch flyback converter using variable switching frequency

This paper proposes a dual voltage regulations of single switch flyback converter using variable frequency control. By adding an adjusted filter to secondary windings, each output shows different tendency according to the switching frequency. This means that even if the switching duty is same, the output voltage might be not equal at the different switching frequency. So the output voltage can be regulated by not only the switching duty control but also the switching frequency control. Though the adjusted filter is added to each secondary windings, the simplicity of circuit and control algorithm which are main features of the flyback converter is not disturbed. The dual voltage regulations of the proposed method is compared with that of the conventional method and the feasibility and performance of the proposed method is verified through experiment using a proto-type converter.