الفهرس 
SummaryOnly 14 pages are availabe for public view
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Abstract
The interest of integrating distributed generation (DG) will be increased more and more for the next few years. This can be explained by several factors such as fuel supply to the traditional power stations, the reliability of supplied power to customers and the environmental concerns. The smart grid is introduced to increase the penetration of renewable sources of energy to the traditional electric grid and to efficiently deliver a sustainable, reliable, economic, and environmentally friendly power to customers. One of the ambitious targets of the smart grid is to share the electric energy generated by renewable sources through all the networks. With the increased penetration levels of DG units, the conventional structure of the current distribution systems is expected to be changed into multiple interconnected distribution systems called microgrids. Integrating DG to the distribution system has different impacts on voltage profile, power flow, reliability, quality, stability and protection. With the integration of DG to the distribution system, distribution systems are in transition from unidirectional power flow systems to bidirectional power flow systems. The main technical barrier for DG integration is the voltage rise at the DG bus due to excessive generation. The first contribution of thesis is to obtain the maximum size of DG to be connected to the distribution system considering both the voltage and power flow limits. The maximum size of DG is calculated at the point of maximum generation& minimum load. The method implemented here also considers the amount of reactive power drawn from the transmission system. The main contribution of thesis is to optimally locate and size one or more distributed generation units (DGs) to the distribution system according to multi-objective function. This research proposes a new optimization approach for maximizing the DG size both system losses and mean average voltage deviation. Both the voltage and power flow limits are considered here for all system operating points.
With the presence of DGS in distribution system, the traditional voltage and reactive power control becomes insufficient to overcome all voltage and power flow problems. A multi stage voltage control method is presented here to control any voltage and power flow problem for the distribution system in the presence of DG. The method proposed here considers the rated reactive power drawn from the transmission system that keeps the voltage of transmission buses within limits. The proposed optimization and voltage control methods are tested on both IEEE 33bus & 69 bus radial distribution systems.