Simple topologies for single phase AC line conditioning

A variety of single phase AC line conditioning approaches are presented. The topologies use a minimal number of devices and feature buck-boost voltage regulation capability without a transformer, while preserving a neutral connection which is common with the input AC line. The simplest form of the converter is seen to be an AC voltage regulator with output voltage range of 0-2 p.u. with reasonable line current waveforms. Modifications allow the circuit to operate with fully controlled input current. The circuit can be further extended to provide significant ridethrough capability without using a battery. A full function single phase UPS can also be realized if required. Analytical, simulation, and experimental results are given.<>