الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
MicroGrids are power generation and distribution systems in which users and generators are in close proximity. They usually have limited power generation capacity, and are networked together to meet a small area’s load demand. A MicroGrid (MG) can operate interconnected to the utility grid, or as autonomous mode. MicroGrids are likely to be more occurring in the future distribution grid. The interconnection of large amounts of non-traditional generation causes problems in a network designed for conventional operation. The use of power electronics interface offers a potential solution. The power electronics (PE) are required to interface the distributed generation with the MG. As optimal operation and cost minimization of the MGs have received much attention recently. This thesis presents a generalized formulation to determine the optimal operating strategy and cost optimization scheme for an
electronically–coupled MicroGrid as usually used in economic dispatch problem but in the MG as special case that have two types of constraints power electronic constraints and power flow constraints. The major objective is to minimize the overall operating cost considering both the power system and power electronics constraints in the two modes of the MG operation. The thesis presents a generalized formulation to determine the overall cost minimization scheme for an electronically weak-coupled MG including renewable sources with negligible fuel cost and low operating cost compared with conventional sources. The major objective of this work is to operate the MG system optimally and minimize the overall operating cost considering both the power system and the power electronics constraints in the two modes of the
MG operation (connected with the grid and autonomous modes). Both photovoltaic and wind energy conversion systems are considered as the distributed generation (DG) in this work. This thesis also presents steady state, fundamental-frequency models of power electronic converter/inverter systems for coupling DG units to the utility grid based on Newton-Raphson and the developed models. Matlab programs are developed to represent the proposed algorithms. The program is tested in various network conditions and verified by applying them to a MG with three DG units during the two modes of operations (connected with the grid and autonomous mode).