Drone-mounted technology to monitor National Grid’s transmission network

National Grid and The University of Manchester have partnered to develop a new drone-mountable system that will allow real-time, live inspections of the Grid’s overhead transmission line insulators.

Since 2018, the UK National Grid has invested around £5 billion to upgrade, adapt and maintain the electricity transmission network. It plans to spend £9bn on the network by 2026 with further multibillion-pound investments by 2030 to deliver an “affordable, resilient and clean” energy system.

This three-year, £1.1 million innovation project, funded by Ofgem’s Network Innovation Allowance (NIA), aims to save time and cost with the initiative estimated to recover £2.8m over a 15-year period.

Insulators are often made of glass or ceramic, according to National Grid, and protect pylons from current on the power line to prevent the tower becoming live. They produce electric fields when in operation which have distinct profiles, which are altered by defects on the insulator.

“A purpose built electric field sensor system could be flown by drone near to a pylon to analyse insulators’ e-field profiles and assess their health, without the need for circuit outages, line-workers scaling pylons, or insulator samples being sent for forensic analysis,” the British utility company said.

The technology will be developed and tested in The University of Manchester’s High Voltage Laboratory, which is equipped with facilities that can test up to 600kV DC, 800kV AC and 2MV impulse, and has been the testbed for developing pioneering solutions such as improved designs of high voltage overhead lines.

“…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.

“With demand increasing, we need to maximise the resilience of overhead lines, the spine of UK electricity. The ambition of this project helps us address this challenge while moving the UK one step further towards a low carbon future that that ensures reliability and value for the consumer,” added Dr Vidyadhar Peesapati from The University of Manchester.

As well as developing an airborne system, the project will also create digital twins for a range of insulators to define electric field profiles under different conditions, design algorithms to best assess insulators’ condition, and re-engineer and miniaturise the tech into a drone-mountable system.

One challenge the project is aiming to overcome, according to National Grid, is to develop an algorithm to assess insulators’ condition while distinguishing between the effects that pollution can also have on the electric field.

The project follows a separate NIA-funded project in which National Grid is trialling autonomous drones for visual monitoring of pylons and overhead lines.

With drone tech estimated to add billions to UK economy, according to industry experts, it may not be too bold to expect more businesses investing in the industry soon.