Methods for the Optimal Design of Grid - Connected PV Inverters

Abstract

The DC/AC inverters are used in grid-connected PV energy production systems as the power processing interface between the PV energy source and the electric grid. The energy injected into the electric grid by the PV installation depends on the amount of power extracted from the PV power source and the efficient processing of this power by the DC/AC inverter. In this paper two new methods are presented for the optimal design of a PV inverter power section, output filter and MPPT control strategy. The influences of the electric grid regulations and standards as well as the PV array operational characteristics on the design of grid-connected PV inverters have been considered. The proposed methods have been applied for the optimal design of PV inverters installed at various sites in Europe. The simulation results verify that the proposed optimization techniques enable the maximization of the PV energy injected into the electric grid, thus serving as a tool to gain more energy by the optimized PV installation.

Keywords

• Photovoltaic power systems; DC-AC power conversion; Design methodology; Optimization methods

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