This project presents the design of a flyback converter operating in Discontinuous Current Mode (DCM). DCM ensures simplified control and naturally eliminates diode reverse recovery, reducing switching losses and improving efficiency. The design process includes the selection of magnetizing inductance, output capacitance, transformer turns ratio, and appropriate magnetic components.
The converter is specified for 15 V input, 19 V output, 75 kHz switching frequency, and 50 W rated power, while ensuring correct operation up to 100 W. Output ripple is kept below 1% thanks to optimized capacitor sizing, and a maximum duty cycle of 0.45 is respected.
Validation through PLECS simulations confirms operation in DCM under both rated and maximum load. Simulation results provide inductor currents, MOSFET and diode stress levels, and voltage ripple analysis, which guide the magnetic design. Transformer core sizing, conductor selection, and fill factor verification demonstrate feasibility and robustness of the final design.
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