Grid-connected Soft Switching Partial Resonance Inverter for Distributed Generation

This paper presents current control method for a grid-connected partial resonant soft switching inverter. This inverter does not use an electrolytic capacitor and is capable of boosting and bucking the voltage. Grid-connected inverters are used to integrate distributed energy sources to the grid. Current control is vital in meeting the standards and requirements when connecting to the grid. The closed-loop current regulation for this type of converters is analyzed and design guidelines are provided. The control is implemented in the synchronous frame. In addition active damping techniques using capacitor voltage and inductor voltage feedback is used to mitigate CL filter resonance at the output. The mentioned control strategies are implemented on a 400W lab prototype and the results are presented.