Comparison between PWM and sigma-delta modulation in a power factor correction system

In this work, the sigma-delta (MA) and the PWM techniques in boost power factor correction (PFC) systems, are compared. To make a comparison under the same power section operating conditions, the problem of evaluating the average switching frequency arises. Electromagnetic emission for both configurations is also investigated. The results show that the MA approach represents an effective solution for obtaining low distortion and that the introduction of a third level allows it to operate in DCM. Theoretical results were confirmed by simulations and experimental results on a laboratory prototype.