Uninterrupted Power Supply in Rural Overhead Networks by Means of Recloser Application

摘要

Reclosers are self controlled device, which are designed for switching load and fault currents under remote operation. This makes reclosers a unique device with interesting functionality and special requirements for their design. The paper describes design and feature of modern reclosers. It covers the vacuum switching technology of the circuit breaker itself, the integrated sensors, the comprehensive protection and load flow functions, monitoring capability, the smart control logic and various communication features. The increasing importance of the Power Quality metrics SAIDI, SAIFI and CAIDI in assessing Network performance means that the data has be gathered from downstream devices i.e. close to the end customers. Recloser-Controllers have the means to collate the core data. They can monitor the System Voltage magnitude and record deviations where the magnitude drops below (Sag) or rises above (Swell), set thresholds, and count each deviation and classify it by measured time duration, relative to a defined set of time windows. The resultant SIARFI, SMARFI, STARFI and Interruption counts per pole provide the basic data for assessing the Network performance metrics. The combination of these new technologies allows a very efficient operation of distribution networks. A consequent application of reclosers, distribution switches and control units leads to increased reliability of supply and reduced operation costs. This helps to keep the power supplied to as many customers as possible and increases revenue for the utilities where the network is proven to be reliable by minimizing customer minutes lost.