Improve your SAIDI with Advanced Fault Passage Indication

Abstract

Situation as of todayCustomer power outages are due to various causes: on overhead Medium Voltage distribution networks, these could be animals, vegetation, wind effect, cracked insulators, salt crust deposit on isolators, lighting strikes, etc.This creates a network fault that may normally be cleared or isolated by a circuit breaker located at the primary substation.Distribution networks are evolving with the integration of DER.In case of a fault, the fault current flows from multiple power sources: the traditional fault detection system fails and must be replaced with a directional fault detection system (ANSI 67/67N).Network devices fitted with such system indicate whether the fault is upstream or downstream, which helps to quickly reconfigure the MV network.Network devices providing ANSI 67N can also support ANSI 47 Broken Conductor.This specific earth fault occurs when a phase conductor does not touch the ground or touches a highly resistive soil.The primary substation CB may not trip, which might lead to a highly hazardous situation as the broken conductor is still live and people, animals, vehicles or building may touch it by accident.A device fitted with ANSI 47 function may help to solve this issue.Expected benefitsImproved SAIDI through an accurate faults detection and direction indication, quick network reconfiguration and fast restoration of supply to customersImproved safety with the fast detection of broken conductor occurrences.Conclusion.An advanced fault indication helps to faster restore power and make the network safer.