الفهرس 
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Abstract
ABSTRACT
In recent years, renewable energy sources have attracted a great deal of
attention as a key solution to fossil fuel depletion. Photovoltaic (PV), which is the
direct conversion of light into electricity, has emerged as one of the promising
paths to achieve a transition to sustainable energy across the world. However,
under different operating conditions, the voltage and maximum power produced
from the PV array can vary.
Typical PV system consists of PV modules, DC-DC Converter and an MPPT.
MPPT controls the DC-DC converter that acts as a coupling stage between PV
module and load. A DC-DC converter is a device that transfers a DC supply’s
voltage from a level to another. Researchers face many challenges in designing
converters with maximum efficiency, small size, reduced cost, and minimize
switching losses. For the PV system applications, a conservative step-up (boost
converter) can be used. This converter has a simple structure. The step-up (boost)
converter is pulse controlled, when the duty cycle is near to hundred percent, the
gain approaches infinity. But, practically, the static gain is restricted because of
losses associated with the inductor, switch, diode, and capacitor.
This thesis aims to use a PV model for the simulation of photovoltaic arrays
and thus to propose a method for tracking the maximum power point using
alternative control methods for DC-DC converters. Besides, the thesis will focus
on a comparison between the proposed method and Perturb and Observe (P&O)
and Incremental Conductance (IC) methods that are used for maximum power
point tracking. The proposed system consists of a PV model, a DC-DC converter,
a VSC, a transformer, and a grid to simulate a real-life situation.
Furthermore, the P&O and IC as well as P&O and Cuckoo Search Algorithm
(CSA) in combination will be investigated to reveal their effects on the general
efficiency of the PV system. A Matlab/Simulink is utilized to show the impact of
these methods on the PV system in various cases. According to the simulation
results, using a combination of the above-mentioned maximum power point
tracking methods (ICM-P&O/CSA-P&O), it provides a faster response under
rapid changes in operating conditions than using conventional P&O and IC
methods alone. At the end of the thesis a practical experiment is presented which was
conducted to verify one of the methods discussed in it.