A single-phase cascaded H-Bridge inverter for grid-tie photovoltaic system addressing the problem of unbalances in H-Bridge cells

This paper presents the performance of single-phase modular cascaded H-Bridge five level inverter for grid-tie photovoltaic applications. Two H-Bridge cells are cascaded, each cell connected to a string of PV panels. The control scheme adopted maximizes the power transferred from the PV cell to the utility, via the grid, generates a sinusoidal current with minimum harmonic distortion, which is fed to the grid and balances the DC link voltage of each H-Bridge Cell (HBC). Maximum power point is tracked in the PV system using MPPT (Maximum Power Point Tracking) algorithm. The performance of the adopted control scheme has been investigated through MATLAB Simulations.