Drones and robots combine for transmission line monitoring

Canada’s Hydro-Québec has developed LineDrone for transmission and distribution line lifecycle management.
Published: Mon 12 Mar 2018

Drones and robots are becoming increasingly popular with utilities for the inspection of powerlines and other use cases where human intervention is either impractical - such as in pipes or underground locations - or would be more costly or dangerous, such as in remote or hard to reach locations.

The range and availability of devices is increasing, they are becoming more sophisticated and prices are dropping.

Hydro-Québec combines drone and robot

While drones and robots are different technologies, combining the power and capabilities of the two would open up new benefits for users. This is what Canadian public utility company Hydro-Québec’s research institute (IREQ) is doing with its LineDrone project.

Hydro-Québec manages generation, transmission and distribution of electricity in the province of Quebec. With more than 34,000km of overhead lines, much of it dating from the 1960s and ‘70s, ageing of the lines both externally and internally has become a key concern.

IREQ has been developing the use of drones and robots since as far back as 2000. Among the solutions subsequently commercialised is a robotics platform named LineScout for inspecting and maintaining energised overhead transmission lines. LineROVer, more compact and lightweight, is another, originally developed for de-icing overhead ground wires and conductors but also now incorporating transmission line inspection and maintenance applications.

LineCore, can be used as a stand alone or mounted on the LineScout or LineROVer for corrosion detection on transmission and distribution line conductors.

And new out of the box is the LineRanger for inspection of transmission line conductor bundles, with the ability to cross obstacles and cover several kilometres per day.

LineDrone takes off

LineDrone is an in-house developed drone-based platform with an onboard vision system which enables it to recognise powerlines and to automatically align with the conductor for landing, according to a company news release. In this semi-autonomous mode, the pilot no longer has to stand directly beneath the powerline for the landing. This is especially useful for high altitude landings, when the visual precision to line up the drone is lacking.

Once the drone lands, its propellers are stopped and with specially designed motorised wheels it can then patrol the cable equipped with for example, the LineCore technology or another dedicated payload.

“Using such an airborne system to bring a sensor into direct contact with the transmission line significantly accelerates and simplifies the conductor inspection process,” says Serge Montambault, Manager of IREQ’s inspection and maintenance robotics unit.

Furthermore, as the drone can fly over obstacles such as towers, clamps and sleeves and as the motorised LineCore can move along the conductor using very little power, the inspection can cover many spans without recharging the battery. This means of deployment also makes it possible to move quickly from one phase conductor to another for detailed assessment of all conductors on strategic spans, the news release states.

Montambault notes that since its development in 2013, LineCore has been deployed on six transmission systems in three countries.

“The most recent milestone in the deployment of LineCore and other sensing technologies is undoubtedly the development of drones that target very specific and challenging missions,” he says.

The LineDrone is still in the developmental stage and next steps include adding a new sensor and progressing towards autonomous capability, Montambault says.

Drone and robot energy use cases

The availability of such solutions equips transmission and distribution operators with a powerful new tool to support the management and maintenance of these critical assets both in day-to-day and emergency response situations.

Nevertheless, the technology is still emerging. For example, use cases under development at the US Electric Power Research Institute (EPRI), which has been studying the use of drones and robotics in the power sector for almost two decades, include robots for internal inspection of transformers and for substation security.

In another current project, EPRI is working with American Electric Power to permanently install a robot to make regular inspections on a 138kV transmission line in Columbus, Ohio. The robot is powered by energy harvested from the currents in the shield wire.

Illustrative of the opportunity potential, Navigant Research projects the global drone and robotics market to grow over the next decade from approximately $2bn in 2017 to over $13bn in 2026.

The use of robotics and drones as a service is also expected to double in most regions. The latter in particular is ripe for specialist services, with regulation evolving in many countries and the generally stricter conditions around commercial operation.

Photo credit @Hydro-Québec