MPP tracking optimization of complete PV installations attaining minimum losses

The problem of locating the maximum power point (MPP) of photovoltaic (PV) systems with the impact of the power losses taken into account, is extensively analyzed. As the connection of large PV systems in modern power grids needs numerous cables and utilizes an interface of power electronic devices, namely dc/dc boost and voltage source converters (VSCs), the induced residual losses cannot be neglected. Losses affect both, the true power injected to the grid and the procedure of tracking the MPP, a fact that becomes essential under distinct shading conditions. In this paper, since losses are heavily reliant on the current flowing through a corresponding device, a novel approach that integrates the minimization of losses together with the MPP tracking procedure into an optimization problem, is developed. As the optimization of a PV may include more than one local solutions, a fact that occurs under partial shading conditions, it is important to notice that the proposed methodology recognizes the globally optimal solution. Hence, in contrary to other conventional techniques, it substantially enhances the efficiency by realizing the right MPP implementation. Finally, to properly assess the importance of the losses analysis and to evaluate the proposed optimization scheme, simulations are conducted for a PV array connected to the grid through a dc/dc boost converter in series to an inverter with their complete control schemes involved.