A single-stage high power factor voltage regulator with reduced intermediate bus voltage stress

In this paper, a single-stage AC/DC power-factor-corrected voltage regulator (PFCVR), which permits a direct transfer of partial input power to the output after the first power process, is presented. This technique results in lower voltage stress on the intermediate bus storage capacitor and improved conversion efficiency while achieving high power factor. The duty ratio is a function of the load so that the bus voltage decreases when the load becomes light. Experimental results to verify the theoretical analysis and performance of the PFCVR are reported.