INFRASTRUCTURE ENHANCEMENT FOR RESTORATION OF DISTRIBUTION-SYSTEMS FOLLOWING EXTENDED OUTAGES

Advances in micro-electronics, computers, and communications technolog y has made it possible to automate several functions in distribution s ystems. Such automation will make delivery of electricity more efficie nt, enhance reliability, and lead to more effective utilization and li fe-extension of existing electricity distribution infrastructure. More over, distribution automation offers opportunities for implementation of new functions. With certain enhancements in the distribution system infrastructure maximum benefits of distribution automation can be acc rued. In this paper, an example of such infrastructure enhancement is presented. Specifically, application of remotely controlled three-phas e and single-phase sectionalizers in restoration of power in distribut ion systems following an extended outage is presented. The remotely co ntrolled sectionalizers can be opened and closed to supply power to sp ecific parts of the system. Thus, restoration can be done in steps usi ng these sectionalizers. Therefore, the firm capacity of substation tr ansformers in a distribution system can be decreased. A delayed expone ntial model is used to represent the load characteristics during cold load pickup following an extended outage. The maximum and the minimum restoration times are determined for two different arrangements of sec tionalizers. Also included in the paper is a brief description of SCAD A, AM/FM and their relationship to distribution automation, and a shor t description of communication infrastructure needed for implementatio n of a Distribution Management System (DMS).