Modeling of on-grid photovoltaic power systems and investigation effects on the grid of photovoltaic power systems

The use of grid-connected photovoltaic systems is increasing day by day and this increase leads to detailed investigations on photovoltaic systems and grid effects. With these researches, it is aimed to reduce various problems arising from photovoltaic systems, to perform performance analysis and to increase energy quality. Today, researches on grid-connected photovoltaic systems are still in progress. In this thesis study, a grid-connected photovoltaic system was modeled in MATLAB/ Simulink to observe the synchronization process between the photovoltaic system and the grid and the effect of the harmonics originating from the inverter in the photovoltaic system. With this work in the simulation environment, it is aimed to operate on-grid photovoltaic system more efficiently, to reduce the harmonics to the minimum and to show the working period of the photovoltaic system and grid together in the simulation environment. In the first part of the work, brief information about on-grid photovoltaic systems was given, followed by briefly information about the previous studies and the scope of the thesis. In the second chapter; detailed information about previous studies on photovoltaic systems has been given. After, general information about solar batteries, photovoltaic system, power quality and harmonics is given. In the third chapter; Each member of the on-grid photovoltaic system is modeled in MATLAB/Simulink and necessary calculations are made for the elements. In the fourth chapter; Frequency, phase, voltage, power and harmonic measurements of the photovoltaic system and the grid. In addition, voltage and frequency stabilization times between the photovoltaic system and the grid in the synchronization process and voltage increases in the grid are shown when there is no load in the system. The voltage, power, frequency and phase angle values measured in the photovoltaic system, load and grid are shown separately after synchronization. In the fifth chapter; the performance of the photovoltaic system was analyzed according to the graphs and measurement values resulting from the simulation, and the results obtained were interpreted and discussed in general.