الفهرس | Only 14 pages are availabe for public view |
Abstract In this thesis, a powerful cut-set reliability evaluation algorithm is introduced. The effect of protection system operation on power network reliability is considered. The technique identifies and groups sets of protective breakers and computes their probabilities according to their fault erasing priority. Considerable modification in the reliability indices is attained by including outages resulting from probable backup protection operations. Breakers of high impact on system reliability are determined. The cut-set technique provides adequate handling of large power networks subjected to high amount of common faults. Also, a developed eleven states Markov model is introduced. This model simulates the protection system operation with respect to the concerned power elements. The developed model representing the actual states of protection and power systems, has the advantages of extending and improving the existing previous models. A new protection system reliability index is proposed in this work to relate power system (or components) unavailability to the various failure modes of protection system. The risk associated with neglecting the repair at the onset of protection failures recognition is also assessed. A technique for investigating protection relaying schemes• based on the former indices is presented. This method weights the effectiveness of the different available schemes by simulating the modes of their components and considering their impact on the concerned power system. |