Modeling and control of grid connected photovoltaic systems

Abstract

In grid-connected Photovoltaic (PV) applications, DC-links based on large electrolytic capacitors, which introduce reliability problems, are used to attenuate voltage oscillations caused by the sinusoidal power injection into the grid. This paper proposes the unified modeling of the complete PV system in grid-connected operation to design control strategies that mitigate the DC-link voltage oscillations as well as irradiance disturbances caused by environmental perturbations, it making feasible the use of non-electrolytic capacitors. The developed control strategies have been associated with a maximum power point tracking technique to maximize the power produced by the PV panel. Finally, the proposed solution has been validated by means of analytical expressions, simulations, and experimental results.