الفهرس 
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Abstract
The key point of wavelet transform is the ability to extract the transient components from the sampled waveforms and then process these to detect quickly the occurrence of a power system transient. It is a misunderstanding that any wavelet is suitable for any signal and any application. Choosing the right wavelet is crucial for a successful wavelet transform application, but choosing the right wavelet for a specific application has been an open question.
This dissertation consists of two main dependent parts. The first one discovers the suitable mother wavelet for power system transient analysis. The second part, includes the usage of the selected mother wavelet to analyze faulted voltage signals in order to estimate the fault location.
In this dissertation, wavelet techniques are proposed for the analysis of power system transients in order to select the suitable mother wavelet. Many mother wavelets have been used for this analysis such as Haar, Daubechies (db), Symlets, and Coiflets. This dissertation describes a strategy to choose a suitable mother wavelet for this analysis. It also shows the deviation between Matlab and theoretical (mathematically calculated) db¬wavelets when they are used for the analysis of power system transient. The simulation results show that the theoretical db wavelet is more suitable for analyzing power system fault transients than the Matlab db wavelet.
Accurate location of faults on overhead power lines for inspection-repair purposes is of vital importance for operators and the utility staff. This dissertation presents a new method for accurate location of faults on two ended and three ended (teed) transmission lines. The proposed method relies on the accurate detection of the arrival time of the reflected voltage wave from the fault point to estimate the location of the fault. The method works off-line utilizing voltage samples that are recorded prior to circuit breaker tripping. Discrete wavelet transform is used to analyze the voltage samples and detail 1 is obtained. The sample number corresponding to the first peak in detail I represents tpe arrival time of the reflected wave from the fault location. A linear relationship is developed between the sample number and fault location. This relationship is used to find the fault location on two-terminal lines; series compensated lines, mutually coupled lines and teed lines.
The simulation study is carried out using PSCAD simulation program. The results are then interfaced to Matlab where the algorithms are implemented.
Jndex Terms-- Power system fault transients, Daubechies wavelet, Fault Location, teed lines, transmission lines, Wavelet transform and Traveling Wave.