Analysis and Control of a Novel Transformer-less Grid-Connected Single-Stage Solar-Inverter using PR -Controller

This paper proposes a novel grid-connected transformer-less inverter topology with boost converter followed by flyback inductor inverter. The proposed inverter is of common-ground type, hence the leakage current flow between PV-panel and ac-grid is zero which is desired in transformer-less inverters. The proposed inverter provides symmetrical voltage gain both positive and negative, hence any simple PWM technique can be implemented. The proposed inverter detailed steady state analysis, and the design equations are presented. The inverter small-signal model is developed, and the detailed design of PR-controller is presented for inverter closed-loop operation with grid. The inverter analysis and the designed controller are verified with the both simulation and experimental results.