Single-stage Power Factor Correction Ac / Dc Converter

To reduce the component counts and the cost, the single-stage power factor correction.(PFC) techniques have attracted more and more atention. A single-stage PFC converter combines the PFC stage and a DC/DC converter into one stage with a shared switch and controller, which is analyzes and researches in this dissertation. First., the basic single stage power factor correction converter with a boost type input current shaper is studied. Operation principle and characteristics of the single stage PFC converter are thoroughly analyzed. In sigle-stage PFC approach,there are two important issues of concern. One issue is how to give the system a high ereficiency.. Another one is how to control the energy-storage capacitor voltage below 450V.The single-stage PFC onverters of Boost type can be classified as 2-terminal ICS cell and 3-terminal. ICS cell. .The two cells also be thoroughly analyzed. Then concept of "direct- power -transfer" is derive. Finally, a novel single stage power factor correction converter which can implement direct-power-transfer is studied. Operation principle and characteristics of this converter are analyzed in detail. The new converter with "direct -power - transfer" can control the energy-storage capacitor voltage below 450 V, .and have a higher efficiency and PFC. Finally it can be seen from .the experimental results that .the performance of .the. novel single stage power factor correction. Converter is better than that of .the boost type single stage power factor correction converters.