High power flyback converter

Switch mode power supplies, which have fast transient response and high power density, are widely used in industry. Some issues such as design cost have been most important in designing such a power supply. Many different topologies are given in the literature. Among those, the flyback converter is most popular converter for low and mid range power application. Main feature for that converter is the magnetic component provides energy storage, isolation and transforming at the same time.As in stated Wang vd. (2005, 2006) and Hui vd. (1999) papers, the flyback topology has been attractive because of its relative simplicity when compared with other topologies used in low power (<150W) applications. In addition, Gong vd. (2006) , Lo and Lin (2007) have also proposed new flyback topologies which are operated at soft switching and provide over 80% efficiency for high power flyback converter application (>150W),In this thesis, it is aimed to design a high power flyback converter which is operated at hard switch and provide over 80% efficiency. The output power of proposed flyback converter is 280W. It has 2x150V outputs and both outputs are serial connected to each other, so total converter output voltage is raised to 300V. Maximum output current is up to 0.93 Amp and switching frequency is 132 kHz.First, Flyback converter basic futures have examined. The formulas, which are required to design, have developed. Next, the power switch analyzed, and then realized. The power transformer designed and wrapped according to calculated number of turns and air gap. After the transformer design, application circuit parameters calculated according to Flyback converter formulas. Snubber circuit and power dissipation are also studied. The designed circuit is simulated and simulation results are given. Application circuit is set up and operated on the PCB. 84 % efficiency is measured for the realized flyback converter.