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Projects: Projects for Investigator
Reference Number NIA_WPD_008
Title Improved Statistical Ratings for Distribution Overhead Lines
Status Completed
Energy Categories Other Power and Storage Technologies(Electricity transmission and distribution) 100%;
Research Types Applied Research and Development 100%
Science and Technology Fields ENGINEERING AND TECHNOLOGY (Electrical and Electronic Engineering) 50%;
ENVIRONMENTAL SCIENCES (Earth Systems and Environmental Sciences) 50%;
UKERC Cross Cutting Characterisation Not Cross-cutting 100%
Principal Investigator Project Contact
No email address given
Electricity North West Limited
Award Type Network Innovation Allowance
Funding Source Ofgem
Start Date 01 July 2015
End Date 01 July 2018
Duration 36 months
Total Grant Value £747,554
Industrial Sectors Power
Region North West
Programme Network Innovation Allowance
Investigators Principal Investigator Project Contact , Electricity North West Limited (99.995%)
  Other Investigator Project Contact , Western Power Distribution (0.001%)
Project Contact , Scottish and Southern Energy plc (0.001%)
Project Contact , SP Energy Networks (0.001%)
Project Contact , UK Power Networks (0.001%)
Project Contact , Northern Powergrid (0.001%)
Web Site http://www.smarternetworks.org/project/NIA_WPD_008
Objectives To monitor the weather conditions and co-incident temperatures of various conductors at various current levels in order to provide a new dataset for the assessment of the weather risk element of probabilistic ratings and to derive a methodology for quantifying this risk, in combination with load risks, in order to calculate line ratings. To update ENA ER P27 and ENA ACE 104. To validate the updated CIGR methodology for calculating conductor temperature from load and weather data, allowing the possibility of future "desk top" re-runs of the project to cover different locations and time periods. To update existing software tools, and to provide a new software tool to enable more comprehensive (regional or line specific) rating assessments to be made. To engage with the Met Office to enable rapid provision of appropriate weather data sets. Sufficient data collection to build a robust model of overhead line ratings. Analysis of that data to produce a model that enables more robust rating of overhead lines than the current model. A new software tool to enable more comprehensive (regional or line specific) rating assessments to be made. A robust, accurately informed revision of ENA ACE 104 and ENA ER P27.
Abstract Distribution overhead line ratings are based on CEGB research work and further assumptions described in ENA ACE 104 and ENA ER P27 published nearly 30 years ago. Recent work testing these assumptions have found some of them to be erroneous, with the result that existing distribution line ratings are now considered out of date. In the meantime, changing demands on networks are increasing the pressure to maximize overhead line capacity. In addition, existing ratings take no account of regional differences in climate, nor of any changes in climate that may have occurred over the last 30 years. Taken in conjunction, this means that load-related decisions to replace or reinforce lines are currently based on inaccurate ratings. Future climate change is predicted to put further pressure on line capacity. Distribution Network Operators (DNOs), therefore, need a cost-effective, up-to-date and robust methodology (supported with the necessary tools) for calculating and optimizing overhead line ratings at both the regional and line specific level, both for today and the future. A previous DNO collaborative project under the Innovation Funding Incentive established an overhead line test rig to monitor weather conditions and temperatures of different conductors at various current levels. Under this project, the test rig will be operated continuously at a set current for 24 months, with conductor temperatures and weather conditions recorded at specified time intervals. At the end of the first 12 month period, an in depth analysis of the data collected will be undertaken. When the data collection activity has been completed, following intensive data analysis the OHRAT and OHTEMP tools (which calculate line ratings and temperatures respectively) will be updated. Revisions of ENA ACE 104/ENA ER P27 will also be completed. Using the data collected and analysed by the project, a more sophisticated overhead line assessment software tool will be developed. This tool will build on the algorithms developed for the OHRAT/OHTEMP update and allow alternative weather data sets provided by the Met Office (or from other sources) to be analysed, enabling more comprehensive line rating assessments (regional or line specific) to be made. By using predicted weather datasets, assessments could even be made about future line ratings, taking climate change into account. In parallel with the data analysis and software tool development, the test rig will continue to gather data, with a second 12 months’ data being used to provide further confidence in the statistical relationships established with the first 12 months’ data.Note : Project Documents may be available via the ENA Smarter Networks Portal using the Website link above
Publications (none)
Final Report (none)
Added to Database 20/08/18