National Grid eyes e-field drone inspection for pylons

Manchester University is working with National Grid to develop a drone-mountable system for assessing the electric fields of overhead lines.

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Funded by Ofgem’s Network Innovation Allowance (NIA), the three-year, £1.1m project will use electric field (e-field) sensor technology to monitor the condition of high voltage insulators on the power lines. These insulators are generally made from glass or ceramic, protecting the pylons supporting the power lines from becoming live.

The e-fields produced by the insulators have distinct profiles, and defects can be detected by changes to these profiles. Equipping UAVs with bespoke e-field sensors would allow National Grid to monitor the insulators and the safety of lines in real-time, making estimated savings of £2.8m over 15 years. The technology will be developed and tested in Manchester University’s High Voltage Laboratory, which is equipped with facilities that can test up to 600kV DC, 800kV AC and 2MV impulse.

“With demand increasing, we need to maximise the resilience of overhead lines, the spine of UK electricity,” said Dr Vidyadhar Peesapati, from Manchester’s Department of Electrical and Electronic Engineering.

“The ambition of this project helps us address this challenge while moving the UK one step further towards a low carbon future that ensures reliability and value for the consumer.”

As well as optimising the sensor hardware, the project will create digital twins for a range of insulators to define electric field profiles under different conditions and design algorithms to best assess insulator condition. The team will also work to re-engineer and miniaturise the sensor tech into a drone-mountable system. The e-field drone project follows a separate NIA-funded project in which National Grid is trialling autonomous drones for visual monitoring of corrosion on pylons and overhead lines.

“We’re increasingly using drones as part of our activities monitoring the condition of our transmission network, and innovations like this e-field sensing system mean there are even more exciting ways that drones could support us in keeping the grid reliable and safe in the future,” said Nicola Todd, head of strategy and innovation and National Grid Electricity Transmission.

“We look forward to working with Manchester’s experts and test facilities to develop new monitoring tech that will help us keep the network in good health while saving consumers money.”