The Study Of Grid-connected Photovoltaic System Based On MATLAB Simulation

With the continuous improvement of the annual gross domestic product (GDP), Chinahas an excessive dependence on non-renewable energy obviously. The energy crisis hasbecome increasingly apparent at present. So, the application of new energy has been more andmore attention. Among them, solar energy has attracted many attentions of the world by itscharacteristics such as renewable and clean. Photovoltaic (PV) grid-connected system hasbecome a focus in the field of new energy development. In order to improve the stability ofthe PV grid-connected system, this article has carried out in-depth study on the batterycharacteristics of PV grid-connected power generation system, inverter control strategy andthe island detection problem.Firstly, this paper introduced the background and significance of PV grid system. Thecomposition and application of PV grid-connected system are. Then the PV cell model wassimulated in the MATLAB/SIMULINK environment, the effect of light intensity andtemperature on the output was analyzed.Afterwards several kinds of PV grid-connected control strategies were introduced. Aftercomparison we concluded that: the compound control strategy, which based on thecombination of phase-locked loop (PLL) technique and feed-forward control of voltage,shows a better effect and the total harmonic distortion (THD) was reduced. In addition, theinfluence of grid-connected system has been analyzed under the islanding issues. Thecommon way of islanding detection was improved. The reaction time was reduced; thereliability of the grid-connected system was increased.