SYNCHRONOUS FLYBACK CONVERTER WITH SYNCHRONOUS BUCK POST REGULATOR

Navnit Kumar, S.Pradeepa, Mohan HR

Abstract: In general, conventional converter is used for converting the power level from one stage to another. But conventional type of converter has slightly more power losses & voltage drop, so efficiency is very sensitive for the low voltage specification and also cooling of dissipative elements floating at higher voltages is a difficult task. So high efficient scheme of synchronous flyback converter with synchronous buck post regulator was approached and low voltage drop, less power losses & very high efficiency was achieved. Where the secondary side of flyback converter including Synchronous buck post regulator floats on the very high voltage line (i.e. 10kV) for the Filament power supply heats the cathode to required temperature to emit electrons in TWT. Filament Power supply based on the Fly back Converter topology which is operated at 100 KHz in CCM mode The Pulse width modulation technique is used to maintain the voltage at desired value using IC. The Post regulator using Synchronous buck topology is implemented for regulating the output voltage of synchronous flyback converter (9.5V DC) to Regulated 6.3V @ 3.3A DC.

Keywords: CCM (Continuous current mode), Pulse width modulation (PWM), synchronous Buck Regulator, Synchronous Flyback converter, TWT (Travelling Wave Tube), SR (Synchronous Rectifier).

DOI: https://doi.org/10.15623/ijret.2014.0304173