Three-phase to single-phase super-sparse matrix converters

Three novel three-phase to single-phase super-sparse matrix converters are described. It is shown that these converters, based on only seven switches, can function similarly to the twelve-switch conventional direct matrix converter. The Z-source and switched-inductor Z-source circuits have recently been proposed for boosting the voltage of power inverters. Here, these circuits have been adopted in the Z-source and switched-inductor Z-source super-sparse indirect matrix converters. To control them, a new modulation technique has been developed. As an example application, the proposed converters constitute a viable alternative to the existing solutions in residential wind-energy systems, where a low-voltage variable-speed generator feeds power to the higher-voltage fixed-frequency grid.