الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
High impedance faults (with or without arcing) resulting from downed conductors represent the most challenging problem for all known protective devices. Many downed conductors conditions were reported by all distribution utilities causing in some circumstances damage, fire or electric shock hazards. Distribution systems, in particular, have their own difficulties regarding fault detection and location methods as compared with high voltage transmission lines. Complex interconnected networks and branched sub-laterals raise different problems considering relaying coordination and fault location computation methods. Also,tapped loads accompanied with load variations affect remarkably the performance of all associated protective schemes. The thesis is concerned with the low voltage distribution system protection problems, where the conventional protection devices such as fuses and overcurrent switches fail to recognize high impedance faults correctly. The main objective of the thesis is
to realize a dependable, accurate and versatile high impedance fault detection and location methodology in the low voltage systems on the consumer side. Towards this goal, the properties of different experimental arcing fault cases are analyzed covering different fault sequences. The obtained results assist to realize a better understanding of the prosperities of these faults and supervise the next steps for getting our aimed detection and location methodology. The next step is to explore the transient profile of their constructed arcs. For this aim, the impacts of load types and loading variations are visualized. Finally, a practical scheme is established and tested for the detection and location of high impedance faults, where different fault discrimination rules are initiated depending on the fault type. All experimental verifications corroborate the efficacy of the proposed detection and location scheme.