A state of art review and challenges with impedance networks topologies

Inductors and diodes in combination with active switches are the basic building blocks of dc-dc converters. When the active switches are gated on then inductors are charged in series and when the switch is off, inductors are discharged in parallel. The principle of these switched inductor topologies are basic building blocks of impedance network topologies. In these topologies, the inverter zero state switching stage is used to make the inductor charged and discharged. Thus a unique impedance network is designed to boost the output. The Z-source inverter is an example of such type of topologies. The impedance network of Z-source inverter is designed to couple the inverter main circuit to input power source. But it has limitations of high voltage stress across the switches. Over the years, numerous other topologies such as quasi-Z-source inverter, improved Z-Source Inverter etc. have been implemented to improve limitations of Z-source inverter and to make it more suitable for the renewable energy applications. This review presents the comparisons of impedance network topologies on their basic structural differences, advantages and limitations along with dc link voltages and boost factor. MATLAB/Simulink is chosen for verification of the analysis made.