Model Predictive Control of Seven-Level Single-Phase Boost Inverter without weighting factor for Grid-Tied Photovoltaic Applications

This paper presents a switched-capacitor integrated 7-level boost inverter for single-phase photovoltaic (PV) applications and its associated control scheme. It consists of three switched capacitors and eleven active switching elements. A boost converter at the front side helps to maintain the capacitor voltage balance during the operation modes. This topology does not require any control scheme to balance the switched capacitors at the DC-bus due to its inherent voltage balancing capability. Thus, it reduces the control complexity. The proposed structure has the capability to integrate low and varying voltage sources such as PV and consequently, reduces the number of components, required input voltage, and control complexity. Finite control set model predictive control (FCS-MPC) algorithm is used to control the proposed inverter. Thermal analysis of the proposed topology is presented for loss calculation of each power devices. Finally, detailed analysis followed by simulation and measurement results is presented at the end.