الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
The integration of Renewable Energy Resources (RERs) has become popular, especially the penetration of distributed generators (DGs) such as Photovoltaic Generation Units (PVGUs), Wind Turbines (WTs), and Hydraulic sources (HSs). RERs can be mixed solar-PVs and wind turbines to minimize the long-term impact of annual carbon emissions concurrent pollution and the high loss across transmission lines. The main structure of low-voltage distribution networks (LVDNs) includes renewable power plants, MV/LV transformers, and PV inverters. The most integrated DGs are rooftop PVs that are more concerned issues due to their low cost of running operations. Highly scaled penetration of PV units with integration of the grid has less impact, contrarily the off-grid system with penetration of PV units has its impacts due to its appropriation on sun irradiance. Its negative sides on LVDN behavior such as; voltage unbalance, system stability, poor efficiency, power quality, frequency oscillation, and accordingly the system inertia and overvoltage (OV) at the point of common coupling (PCC). The solar irradiance may cause overloading at the components of DN, this may lead to an imbalance system between generation and loads sides in LVDNs and voltage unbalance (VU). Hence, the most studied share is the impact of overvoltage. Active Power Control (APC) and installing Battery Storage Elements (BSEs) are the most appealing strategies due to this strategy has the ability to maintain the voltage profile and adjust power, reducing power loss by administering active power outputted from PV inverters and BSEs are able to regulate the system frequency, damping the energy oscillations and exporting the curtailed energy. In this thesis, coordination between APC and BSEs is the applied methodology to regulate voltage, while the first control level is based on the droop control to maintain voltage across PCC by calculating the actual active and reactive power to achieve reference value for voltage value and frequency system, and the second control level is based on Model Predictive Control (MPC). MPC is applied to improve voltage value across PCC after applying droop control. The main purpose of the applied strategy is to mitigate the overvoltage phenomenon and regulate system frequency and voltage through PCC to its nominal value with a smooth waveform. The implemented strategy is simulated in MATLAB/Simulink environment with different case studies. The proposed strategy is implemented on an isolated system with different case studies, the first case is a single PV supplying a constant load, the second case study is a single PV supplying a load change and the third case is random PV units supplying uncertain conditions of load change. The results elucidate that applying MPC is a better control level due to getting the voltage value to its nominal value with a smoother waveform.