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:
- 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
- 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
- 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
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