Feb 2016
Electricity Transmission
Travelling Wave Fault Locator Trial
Feb 2016
Apr 2020
National Grid Electricity Transmission
Aisling Rapier
Click here to send a question to the contact.
Network Innovation Allowance
Overhead Lines, Modelling and Electricity Transmission Networks
A Travelling Wave Fault Locator (TWFL) is to be installed for protection purposes for Delayed Auto-Reclose (DAR) lockout. This is required on composite circuits, where there is a combination of Over Head Line (OHL) and cable sections, for when a fault occurs in the cable section.Deliverables will include the following:

Stage 1

  • Modelling of 2 or 3 different circuits in laboratory conditions to predict performance

  • To set up and evaluate field trials on 2 circuits to check sensitivity.

  • Installation of TWFLs on 2 circuits (one composite circuit and one cable circuit)

  • Implement hybrid circuits in iQ+ on 2 ended circuits.

  • Develop firmware and hardware and conduct lab testing.

  • Set up live trial

Stage 2

  • Evaluate live trials

  • Annual project progress reports

  • Reviewing data once a day for the first three months, to reviewing data to once a week and then once a month

  • Looking at any new results generated

  • Dialling into the TWFLs remotely

  • Downloading transient waveforms

  • Monitoring sensitivity of TWFLs

Stage 3

  • Formulating conclusions from data analysis

  • Deciding whether a TWFL is suitable for DAR lockout

  • Deciding whether a TWFL is suitable for cable fault location

  • Deciding whether a TWFL can be used for condition monitoring purposes

  • Comparing data analysis with system conditions

  • Comparison of data collected and simulation study

  • Final project report with recommendations

  • Evaluating TWFLs to be left on the circuit or to be decommissioned.

  • Decommissioning asset if necessary

The objectives of this trial are to

  • Reduce the costs associated with faults on a composite or cable only circuits by improving fault location
  • Reduce the costs associated with faults on composite circuits with DAR but no DAR lockout capability
  • Reduce the costs of protections systems for new composite circuits, or existing OHL only circuits that become composite circuits by introducing cable sections.
Knowledge gained during this project will allow National Grid to make informed decisions about using Traveling Wave Fault Locators to successfully detect a fault in the appropriate section on a composite circuit; to accurately locate a fault in the cable circuit; and to understand if TWFL will or will not interfere with system stability or other plant functionality.

Specifically we will test Travelling Wave Fault Locator capabilities in the following areas:

  • Test for DAR lockout purposes on a composite circuit

  • Test as a fault locator on a cable circuit

  • Test fitness for purpose when used for condition monitoring purposes

  • To gather data of transience occurring on the system