A Novel Simple Three Level Push-Pull Inverter Suitable for Renewable Energy Based Distributed Generation Systems Applications

The aim of this work is to propose a novel simple three level push-pull inverter topology. Some topologies with the same objective were already proposed, but they have at least two more switches. It turns push-pull into the same complexity level as full-bridge. Of course that it is not desirable, because simplicity is the great advantage of the push-pull. Other proposed solution consists in snubbers. In this case, no switch more is added, but inductors and capacitor are added instead, which may be greater than acceptable and the results may not be as good as expected. This inverter is achieved adding only one switch to the standard push-pull. Its main advantage is the complete control for three level and inductive loads operation while it keeps the simplicity close to that of the standard push-pull. This novel inverter is suitable for applications that require three-level modulation, such as renewable energy based distributed generation systems. In this paper, first the inverter topology is presented, then operation steps are given, describing the operation principle and control law. Finally, simulation and experimental results are shown to validate the topology. The converter performance was found to be excellent