A novel single-stage isolated high power factor correction converter with low voltage stress: dynamics and control

The dc/dc part of a single-stage high power factor correction (HPFC) converter generally operates in continuous conduction mode to increase the output power. However, this results in a high voltage stress across the bulk capacitor of the converter at light loads. The negative magnetic feedback technique is widely applied to deal with this problem. Unfortunately, a dead band in the input current is usually caused by the negative magnetic feedback, which reduces the power factor. To overcome this drawback, a novel single-stage isolated HPFC converter with low voltage stress is proposed in this study. A high power factor is maintained even though the negative magnetic feedback technique is employed in the proposed converter. Output voltage regulation in response to variations in the line voltage and load resistance is also considered in this study. The dynamics of the proposed converter are investigated and a voltage controller is then designed. Finally, the performance of the proposed converter is experimentally verified.