This document reviews different types of transformer configurations that can convert single-phase power to three-phase power or three-phase power to five-phase power. It discusses several research papers on single-phase to three-phase converters using rectifiers and inverters as well as novel transformer designs to directly produce a three-phase or five-phase output from a single-phase or three-phase input. The review covers topics like reliability, efficiency and harmonic distortion reduction of different converter topologies.