| This thesis introduces a new approach to the protection of power transmission systems wherein all the component activities associated with system protection design are gathered together in one integrated environment referred to as the Unified Approach to transmission system protection. These activities consist of automatically generating the most probable abnormal events in the network and analyzing the resulting consequences that arise from these abnormalities. From this analysis, the appropriate characteristics are determined for the relay under study as part of the performance specification of that relay.; The proposed Unified approach overcomes the disadvantages that are associated with the current approaches in which the performance specification is carried out on an ad-hoc basis. In such approaches, it is required to run various programs to estimate the consequences of various types of abnormal events. The results are then reviewed by a protection expert who takes into account various critical situations particular to the system under study and a relay performance specification is produced.; In the development of the concept of the proposed Unified Approach , the ultimate objective is to propose a systematic methodology that will result in improved efficiency in terms of engineering cost and protection design methods. The engineering cost is reduced since this methodology requires a minimum human intervention to process the complex tasks involved. Similarly, the protection design methods are enhanced by the proposed methodology so that they can be processed relatively quickly, be an integral part of power system design, cover all possible events, remove protection design redundancy, specify protection systems according to the power system needs, consolidate protection methods, assure the desired consistency, optimize transmission capacity and assure the security of the power system and the protection system at all times. |
