الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
”Distributed generators, especially Photovoltaic (PV) systems, are the new trend around the world. However, the increased growth in PV in radial feeder causes both voltage unbalance and voltage-rise in distribution networks. Voltage violations depend mainly on the ratings of the connected PVs and their unbalance conditions. The factors that cause high voltage violation, have been investigated in this thesis. Voltage violation mitigation techniques were studied in a literature perspective and, were evaluated using MATLAB/script for verifying their effectiveness. Based on this survey, the most convenient technique is identified to be the energy storage system.Therefore, this thesis proposes an exploitation of coupled batteries with residential PV systems for alleviating voltage unbalance (VU) in radial distribution feeder as an ancillary function. Three techniques for controlling AC-coupled batteries systems have been proposed and compared: “Balancing via the same bus”, “Balancing via the same phase” and “Balancing via the whole feeder” techniques. The proposed control model depends on central controller and secondary controllers. The central controller determines the ratio of compensating batteries’ currents at each bus for mitigating voltage unbalance and ensuring the same value of resultant compensating currents along the distribution network. In the scale of the single bus, the secondary controllers at each bus guarantee that AC-coupled batteries systems in all phases have the same stress or fulfill the shortage in a certain phase. Both Bat optimization and PSO have been used to determine the correct self and mutual coefficients of AC-coupled batteries systems at each phase at the same bus.MATLAB/script was used to represent a distribution network with rooftop PV systems, applying the control scheme and both Bat optimization and PSO. Results of the proposed control scheme verified its ability to mitigate VU under different scenarios of loads and PVs arrangements. The proposed technique gave satisfactory results according to both EN 50160, IEC 61000 standards and Engineering Recommendation P29 in UK.”