Abstract:
The conventional two-stage power converters with bridge rectifiers are inefficient
and may not be practical for the low-voltage microgenerators. This report presents
an efficient ac-to-dc power converter that avoids the bridge rectification and directly
converts the low ac input voltage to the required high dc output voltage at a higher
efficiency. An ac-to-dc converter is proposed in this report which is highly efficient
than conventional method for converting directly ac to a regulated boosted dc. A
boost circuit and a buck boost circuit are connected parallel to an AC input voltage.
During positive half cycle boost circuit is working and during negative half cycle
buck boost circuit is working. But due to the inverting polarity property of buck
boost circuit gives positive dc output. The regulated dc output is obtained from a
dc bus having a single capacitor charged by both the circuits. Simulation results are
presented to validate the proposed converter topology and control schemes. Also a
modified model containing cuk and buck boost circuit is also done and improved the
output current
