Fig. 1 shows the existing single-phase Buck-Boost type acdc converter used to obtain high power factor and sinusoidal
source current. This converter requires an AC filter, four switches with bipolar voltage blocking capability, a reactor in
the DC link, a series connection of a diode and a capacitor in parallel with the DC reactor. Since the switches must have
bipolar voltage blocking capability, devices such as punchthrough IGBTs or MOSFETs, need additional series diodes,
incurring in greater conduction loss.To reduce the number of switches, the topology presented in figure 2 is proposed. This converter requires an AC filter, two switches with bipolar voltage blocking capability, two reactors with magnetic coupling in the DC link, a series connection of two diodes and two output capacitors. Therefore, this topology has the advantage of decreasing the number of switches, thus increasing the efficiency since the conduction losses in the switches are reduced. Given the