Control of series Z-source inverter applied in grid-tied PV system

This paper presents a grid-tied PV system based on the series Z-source inverter. The grid-tied current control strategy, the dc-link voltage control as well as the Maximum Power Point Tracking scheme is realized in the single-stage system. The current control strategy is performed based on dq rotating frame. Indirect dc-link control is adopted to achieve constant peak dc-link voltage and thus can simplify the controller design in inversion stage. The overall control strategy is given and analyzed in detail. Simulation and experimental results demonstrate that the proposed system can be applied in PV system with a wide input voltage range, which verify the correctness and validity of the analysis.