The research described in this thesis covers the analysis and design of impedance-source networks for a wide range of electric power conversion applications (dc-dc, dc-ac, ac-dc, ac-ac). Variance impedance networks, circuit topologies and modulation techniques were analysed, designed and tested in the laboratory to improve performance (efficiency, reliability and power density) of the converter. To achieve this, three distinct approaches were taken in this research, which include: i) investigate and implement a new modulation technique, ii) retrofit existing topologies to get an improved hybrid topology, and iii) investigate a novel converter topology with desired performance.