A PFC Control Circuit for Accommodating Line-Voltage Distortion to Achieve High Power Factor and Low Harmonic Current

This paper proposes a novel power factor corrector (PFC) controller which mainly includes a sine-wave generator, sample-and-hold circuit and feed-forward gain scheduling circuit. With the sine-wave generator and sample-and-hold circuit, the PFC controller can generate pure sine-wave current command for achieving high power factor and low current distortion even under distorted line voltage or during transient operation. Additionally, with the sample-and-hold circuit, capacitance of the dc-link capacitor can be reduced a lot. Furthermore, the PFC controller with the feed-forward gain scheduling circuit is relatively suitable for universal line-voltage applications. Principle and algorithm of the PFC controller and its unique features are discussed and presented in the paper. A prototype realized with a DSP chip and discrete components has been built, from which simulated and measured results have verified the discussed features