Modeling and control of grid-connected photovoltaic energy conversion system used as a dispersed generator

This paper proposes a detailed mathematical model and a multi-level control scheme of a three-phase grid-connected photovoltaic (PV) system used as a dispersed generator, including the PV array and the electronic power conditioning (PCS) system, based on the Matlab/Simulink software. The model of the PV array proposed uses theoretical and empirical equations together with data provided by the manufacturer, solar radiation and cell temperature among others variables, in order to accurately predict the current-voltage curve. The PCS utilizes a two-stage energy conversion system topology that meets all the requirement of high quality electric power, flexibility and reliability imposed for applications of modern distributed energy resources (DER). The control approach incorporates a maximum power point tracker (MPPT) for dynamic active power generation jointly with reactive power compensation of the distribution power system. Validation of simulation results has been carried out by using a 250 Wp PV experimental set-up.