A Larger Step-down Ratio Buck Converter with Reduced Ripple in Input Current and Output Voltage

In this paper, a buck converter with the larger step-down ratio is proposed to reduce ripple in input current and output voltage. The proposed converter achieves lower output voltage at a sufficiently higher duty ratio compare to the conventional buck converter. The proposed converter requires a switch capacitor cell and two inductors. The cell consists of two switches placed in parallel and two crossly connected identical capacitors. Two inductors are required to design the converter. These two inductors are coupled to improve the ripple in input current and output voltage. The operating principle, dynamics of coupled inductor and ripple in inductor currents and output voltage are analyzed. The simulation results of the proposed converter are compared with the conventional buck converter. Finally, the proposed converter is implemented in hardware and the performance of the proposed converter is verified experimentally.