Analysis of the FB-ZCS-PWM converter as a power factor preregulator

摘要

In this paper the full bridge-zero current switching-pulsewidth modulation (FB-ZCS-PWM) converter is analyzed in order to be used as a power factor preregulator (PFP). Firstly, the equations that show its steady state operation are determined and then they are applied to the study of the converter as a PFP. Its dynamic model is found using the transfer functions deduced from it in order to close the current control loop. In order to properly close this loop in power factor correction (PFC), the coefficient values of its transfer function which depend on the the DC operation point along a line semicycle, are deduced by using the notion of "load seen" by the converter in PFC. Finally, the results are verified through simulation and by building a small power converter.