A single-switch 1-phase flyback rectifier operated with a nonisolated dual DC-rail output and a unity input displacement factor

This paper describes a current-controlled AC/DC flyback rectifier that produces a nonisolated split DC-rail output voltage directly from the AC utility supply using one power semiconductor switch and a single magnetic core. The rectifier topologies described represent a low cost means of obtaining a constant power feed to a nonisolated load when a low harmonic distortion of the supply current is desired with an input unity fundamental power factor. The rectifiers can automatically compensate for a load imbalance between the upper and lower output DC rails and energy is supplied to both DC-rails during both half-cycles of the AC supply. A detailed description of the rectifier switching states are given, assuming discontinuous inductor current operation, and experimental results verify the circuit performances