The calculation of ripple current in input capacitor and the resonant voltage of output LC filter in high power buck converter is described. In regard to input capacitor

an accurate formula of calculating ripple current is derived through simulation and deduction

and the maximum ripple current point is stated. Theoretical analysis of the resonant voltage problem occurring in experiments is conducted using certain parameters in a LC filter model

such as inductor equivalent resistance and capacitor ESR. Also a Matlab simulation is conducted to observe its output response characteristics and a damper is added to eliminate resonance. This simple and effective method is verified by simulation and experiment.