This paper presents a variety of single phase ac line conditioning app
roaches. The topologies use a minimal number of devices and feature bu
ck-boost voltage regulation capability without a transformer, while pr
eserving a neutral connection which is common with the input ac line.
The simplest form of the converter is seen to be a ac voltage regulato
r with output voltage range of 0-2 p.u. with reasonable line current w
aveforms. Modifications allow the circuit to operate with fully contro
lled input current. The circuit can be further extended to provide sig
nificant ride-through capability without using a battery. Finally, a f
ull function single phase UPS can also be realized if required. The pa
per contains analytical, simulation and experimental results.