Analysis and measurement of DCM power factor correctors

Analysis of active power factor correctors operating in discontinuous conduction mode is presented. Input currents are modeled as series of triangular pulses with appropriate duty ratios, from which the power factors are computed for three common corrector topologies-the pulse width modulated (PWM) boost, the PWM flyback and the hysteretic boost correctors. Power spectrums are also examined and the harmonic distortions of the discontinuous input currents are computed. Circuit simulations and experimental results are presented in verifying the theoretical analysis.