Study On Reliability Evaluation Model And Application In High Voltage Distribution Networks

Electrical distribution networks are connected directly with customers. It was researched that eighty percent of the total customer interruptions resulted from electrical distribution networks. So, at present, the electric power utilities are more concerned about to satisfy the customers demand with high quality and reliability to the customers. This thesis makes systematic and thorough studies on the theories, models and algorithms for reliability evaluation of high voltage distribution networks (HVDN). The main contents are detailed in the following.â‘  Basic concepts and theories, specific for reliability evaluation of HVDN, are introduced systemically. Characteristics of HVDN reliability evaluation are gi(?) this paper. Advantages and defects of HVDN reliability evaluation method. in the literature, are discussed in the first section.â‘¡ A HVDN reliability evaluation model based on power-flow-technigue is discussed. Some deaper studies,such as scheduled outage model, failuer identification model load shedding strategies, and useful conclusion are detailed in section 3. Indices definitin and algorithm frameaork of HVDN reliability evaluation are also given in this section.â‘¢ Based on the engineering experiences, three kinds of typical network configurations of HVDN are presented in section 4. Then the reliability evaluation is carried out for the three kinds of representatvie configurations using an analytical approach. From the results, we can conclude that the proposed method can prvide valuable reference information for the planners in HVDN configuration design.â‘£ Applying the new abore algorithm to a practical HVDN of Guiyang utility at the voltage level of 220kV(contain 110kV and 35kV), the reliability indices of this system under four system secnarios in 2004 are obtained. After analyzing these results, weaknesses of this network are found.