Modular multilevel inverter with maximum power point tracking for grid connected photovoltaic application

A single-phase modular multilevel inverter based photovoltaic system for grid connection is proposed. This photovoltaic system utilizes two conversion stages; a boost converter for tracking the maximum power point and a modular multilevel inverter used as an interfacing unit. The maximum power point tracking is achieved with a fuzzy logic controller, and the modular multilevel inverter regulates the dc link voltage and synchronizes the grid voltage and current in order to achieve unity power factor operation. The proposed system provides high dynamic performance and power quality injected into the grid. The validity of the proposed system is confirmed by simulations.