Proposed Techniques for Identifying Open and Short Circuit Sections in Distribution Networks

This paper presents novel solutions for three problems encountered in the closed loop distribution systems. The first problem is how to identify a faulty section after being successfully isolated by the protection system. The second problem is how to identify a section affected with undetected open-circuit fault. A novel circuit is suggested in this paper to solve these two problems. The third problem addressed in the paper is how to deal with undetected faults in the 11 KV part of a 132/11 KV network which may result in a complete shut down problems. An effective modification in the trip circuit of the relays protecting the main feeders of the closed loops is suggested to avoid this problem. The validity of the proposed circuits is examined using ASPEN-OneLiner simulation program applied to a real part of Kuwait power distribution network. It is also checked against the specifications of the available equipment used in the real network. The proposed circuits provide fault detection capabilities normally achieved by the advanced and expensive Distribution Automation System (DAS) but with minimal cost. Key-Words:Distribution networks, open-circuit faults, Undetected faults, Ring systems, Fault identification, Fault detection.