Grid connected photovoltaic systems require the use of solid state converters that allow an efficient matching between the photovoltaic generator and the utility grid. Therefore, adequate control techniques, which ensure that the PV generator operates at its point of maximum energy generation under different environmental conditions, are required. This paper presents the design and implementation of a single-phase grid-connected photovoltaic system. Simulation models of the primary generator and power converters were obtained. Additionally, two methodologies for maximum power point tracking by using a new method for estimating short-circuit current are proposed. The proposed method weights the control action at different solar irradiance conditions. In order to verify the behavior of the system, simulation and experimental results are presented. Finally, the conclusions are presented.