Innovative condition monitoring of electricity transmission asset - from science based archaeology to monitoring environmental risks on infrastructure

Lead Research Organisation: Nottingham Trent University
Department Name: School of Science & Technology

Abstract

Environmental factors can accelerate corrosion, e.g. air pollution and salinity in coastal areas are known factors. It is therefore important to understand the relationship between various environmental factors and corrosion to inform asset management policy.
National Grid Electricity Transmission (NGET) network alone has 21,990 steel lattice towers that supports the overhead power lines in England and Wales. NGET inspects the condition of around 3650 steel lattice towers each year. Owing to restrictions on land access as well as the sheer volume of assets, data is captured via colour imagery taken from helicopters. The processing of images to classify the extent and nature of corrosion is a manual task. The grading of the level of corrosion is performed by manual inspection of the images. It was found that the changing light conditions can reduce the accuracy of inspection from colour images. Therefore, 10 percent of these assets are then inspected manually by engineers by climbing up the towers for verification of trouble areas. Overall, the grading of steel health is subjective and time consuming, posing health and safety risks to inspectors.
The proposed project aims to translate technology and methods developed for science-based archaeology in the form of remote imaging at standoff distances to condition monitoring of infrastructure in the energy sector, demonstrating the impact of research in NERC remit to the energy and infrastructure sector and UK economy, initiating step change in condition monitoring of electricity transmission assets. The proposed innovation is timely because it promises automated data capture and analysis with the prospect of producing more quantitative and reliable results. The ability to track condition over time will support an understanding of how these assets perform and deteriorate throughout their lifecycle, and support the ability to predict the optimal time to repair and replace them. Such predictive ability supports a least lifecycle cost paradigm - cost savings that can be passed on to consumers. With demands to continuously improve working practice safety, accuracy of asset surveys and therefore lifecycle costs, the innovation delivers significant maintenance, planning and cost benefits necessary for critical infrastructure assets and society as a whole.
Similar asset monitoring and management issues cross-cuts the infrastructure and energy sectors sectors ranging from railway tracks, bridges, ships, off-shore platforms to pipe lines.

The stakeholders are:
1) The National Grid - national electricity transmission system operator
2) OPUS International Consultants Ltd. - a global infrastructure development and asset management company
3) Mosdorfer CCL systems Ltd. - a manufacturer of overhead power line products

Planned Impact

Benefits to stakeholders include
1. the ability to conduct systematic survey of infrastructure in a reliable, automated and quantitative manner,
2. reducing health and safety concerns for inspectors,
3. reducing labour costs,
4. increase the percentage of asset inspected in a given amount of time,
5. provide early warning of asset integrity;
6. conduct systematic study of the risks of environmental conditions to electricity transmission assets in order to develop environment dependent asset management strategy;
7. new protocol and standards for monitoring of electricity transmission assets using the spectral imaging techniques
8. modify the design of steel components for overhead power line for better durability.

The partners on this project are the National Grid, OPUS international Ltd. (global infrastructure development and asset management company), Mosdorfer (a manufacturer of overhead power line products). The specific benefits to the stakeholders are
1. The asset lifecycle working group at NG will use the system for future inspections, reducing labour costs and improving working conditions for inspectors and ensuring quantitatively comparable monitoring results; will use results from the study to develop environment dependent asset management policies
2. OPUS will potentially use this to broaden their business base to survey electricity transmission assets in the UK
3. The validation of the technology for electricity transmission assets can foster the use of the technology by OPUS in other major infrastructure that act as the connecting forces in modern society. This innovation could become the backbone for how all infrastructure (including land based and offshore) are inspected, reducing safety risks and revolutionising the way we work to be far more efficient and accurate in optimising lifecycle costs. Cost reductions that will be passed on to taxpayers.
4. Mosdorfer can add significant customer value to its product supply by offering; additional pre-sanction engineering services, that deliver remote, safe, accurate cost saving techniques to project planning, for insulator and conductor fitting systems, support structures, towers and substation assets.
5. Mosdorfer can evaluate OHL product integrity with access to all approved fittings, offering digital and mechanical data comparisons of new versus used fittings, to improve design performance, in service lifecycle recommendations, and safer installation techniques for a full range of individual products and conductor string set elements.

Publications

10 25 50
 
Description A method has been developed to automatically calibrate images of pylons in multiple spectral windows and to automatically classify areas that are corroded. This process is a significant improvement over the current manual grading of each pylon so that a decision can be made as to whether they need to be repaired.
Exploitation Route We are currently working with the National Grid to test our method further and see if it can be implemented as business as usual asap.
Sectors Aerospace, Defence and Marine,Agriculture, Food and Drink,Construction,Environment,Culture, Heritage, Museums and Collections,Transport

 
Description AI for DigiLab
Amount £100,000 (GBP)
Funding ID AH/T013184/1 
Organisation Arts & Humanities Research Council (AHRC) 
Sector Public
Country United Kingdom
Start 02/2020 
End 01/2021
 
Description Automated assessment of steelworks condition
Amount £200,000 (GBP)
Organisation National Grid Network Innovation Allowance (NIA) 
Sector Private
Country United Kingdom
Start 04/2019 
End 09/2021
 
Title automatic calibration of spectral imaging data capture under daylight 
Description A system was developed to calibrate remote outdoor imaging spectroscopy data captured during daylight to correct for daylight variations. 
Type Of Material Improvements to research infrastructure 
Year Produced 2020 
Provided To Others? No  
Impact This will be published soon. 
 
Title improved machine learning software for the automatic analysis of spectral image cubes 
Description python based automated analysis of large sets of spectral imaging data cubes 
Type Of Technology Software 
Year Produced 2019 
Impact Not applied to a wide field yet but there is potential for use in a wide range of fields from heritage science to asset management