THE IMPACT OF SWITCHING DEVICES AND BACKUP SUPPLY ON ENERGY NOT SUPPLIED OF A MV FEEDER

摘要

This paper gives mathematical expressions for determining energy not supplied of a medium voltage (MV) power distribution feeder on which different switching devices can be installed. It analytically and graphically presents the impact of switching devices and backup supply on its amount. Depending on location of failure occurrence, on existence of backup supply and the number, placement and type of installed switching devices, the paper describes the sequence of switching operations for the purpose of fault detection and isolation, direct service restoration for the part of network where it is practicable and finally achieving normal pre-fault state. The paper also defines the outage times affecting individual customers or load nodes on the feeder. For simpler analysis, it is assumed that the feeder is uniformly loaded. Regarding this assumption, we give the expressions for optimal locations of switching devices and minimum energy not supplied in cases without and with backup supply. By taking into consideration costs of switching devices and cost of energy not supplied, we describe the total costs as a function of the optimal number and types of switching devices on the feeder.