الفهرس 
CHAPTER 1: INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
In recent years, concern over the quality of electric power has been increasing rapidly since poor electric power quality causes many problems for the affected loads, such as malfunctions, instabilities, and/or short life time.
Poor quality of electric power is normally caused by power line disturbances such as impulses, notches, momentary interruptions, over-voltages, under-voltages, and harmonic distortion.
Harmonic have been shown to have delirious effects on equipment including transformer, rotating machines, switchgear, capacitor banks, fuses and protective relays. Electronic power converters have become one of the major sources of harmonics in the industrial environment due to its non-linear characteristics.
The general procedure in analyzing any harmonic problem is identifying the worst harmonic condition, then designing a suppression scheme and rechecking for other conditions.
In order to quantify the distortion in current and voltage waveforms in a power distribution system, the harmonic simulation is analyzed.
To determine the existence of the harmonic mitigation and resonant conditions, the Fast Fourier Transform (FFT) and new analysis techniques are used. These new techniques are the Short Time Fourier Transform (STFT), the Continuous Wavelet Transform (CWT), the Discrete Wavelet Transform (DWT), the Multi Resolution Analysis (MRA), and Smoothed Pseudo Wringer-Vill Distribution (SPWVD) takes into account time changes in signal spectrum. However the most common and suitable method for harmonic analysis is the FFT.
For compensating the harmonics generated in electric distribution systems, shunt passive filters which have low initial cost and low losses, have been broadly used.
The main objective of this thesis is to design parallel single tuned shunt passive filter to achieve two purposes. The first purpose is to minimize the apparent power for a given and optimal quality factor. The second purpose is minimizing the cost of filter and its losses using the linear programming (LP) as a conventional technique and Fuzzy Linear programming (FLP) as a modern optimization technique.
A mathematical model for the filter total costs, which are the sum of total cost losses in the filter limb and its components cost are obtained. Then, it is considered as an objective function subject to some constraints which are the filter parameters (R, XC, and XL), resonant impedance and the quality factor. The optimal quality factor determines how sharply the filter is tuned to the target harmonic order, the optimal filter parameters are obtained using LP technique.The uncertainty in the filter losses cost, filter components cost, and the quality factor leads to use the application of Fuzzy linear programming technique.In this thesis, the Underground Ramsis Metro Substation (URMS) is considered, and the power quality problem is improved for a selected distributor, which is feeding number of rectifying units. The direct current output power of these units is supplied to the Metro train units.