Control strategy of a single-phase two-stage transformerless grid-connected PV system

Renewable energy which is increasingly in demand. This growth is justified by the limit and the pollution of fossil energy and the increase of the energy deficit. Consequently, several energy strategies that integrate a renewable energy, in order to compensate for the disadvantages of fossil energy and the energy deficit. In particular a photovoltaic energy is one of them. It’s clean and less noisy. It is used as stand-alone or connected to the grid. In this paper, the improvement of the control and the quality of the energy that flows in a photovoltaic system, which connected to the single-phase grid without a transformer, that is well aimed. The two stages configuration are used. Thus, the power line is composed of a photovoltaic generator, a Boost converter, a Half bridge inverter, a passive LCL filter and grid. The basic idea of this paper is to optimize the power quality through a suitable passive filter, a suitable inverter and making a good choice of regulator parameters. In order to verify the proposed control, it is tested under MATLAB.Simulink under different meteorological conditions such as variable irradiation.