Reducing distortion in peak-current-controlled boost power-factor correctors

Abstract

At light load and/or high line, the peak-current-controlled boost power-factor corrector has considerable distortion. In this paper, the authors determine the line-current waveform and the distortion of the corrector, the shape of the ideal reference signal, and discuss and analyze three distortion-reducing methods. The distortion-reducing methods are: (1) adding a variable DC offset to the sinusoidal reference; (2) predistorting the sinusoidal reference with a nonlinear network; and (3) converting the peak-current-control scheme into a simplified average-current-control scheme. The paper presents analyses, practical considerations, and experimental results.