Drone Detects Power Line Problems Using Ultraviolet
Nick Rymer, SWOSU, NIA, NASA LaRC
Andrew Moore, NASA LaRC
Matt Schubert, AMA, NASA LaRC
James Hubbard, UMC, NIA
Drones are powerful tools for utility companies. Using a drone, or unmanned aerial vehicle (UAV), utility workers can find power line problems from the ground - without sending people up a 75 foot high utility pole to visually check lines. That’s important because utility work is the eighth most dangerous job in the U.S. (Source: 2013 Bureau of Labor Statistics).
The purpose of this project is to demonstrate safer, cheaper ways of using UAVs to detect power line problems. When a power line starts to wear down, something called a ‘corona’ forms. Coronas are the breakdown of the air around a high-voltage conductor. Coronas emit ultraviolet (UV) light and are invisible to the naked eye, but UV photosensors can easily detect them.
Three UV photosensors were attached to a UAV facing forward, backward and to the side. The UV photosensors were then connected to an onboard alarm that flashes light and makes noises whenever it senses a UV source. The idea is that the UAV flies along a power line until it encounters a corona, then the corona’s UV light is detected by the UV photosensors and the alarms are triggered. This alerts utility companies to the exact location of coronas so they can quickly send utility workers to make repairs.
First, the UAV was tested at the Electric Power Research Institute to verify that the UV photosensors and alarms worked using a live 100kV corona source. As the UAV passed the 100kV corona source, the UV detection alarms triggered. After this calibration, a tethered flight was performed at the National Institute of Aerospace (NIA) to verify realistic operation. The UAV was flown past the UV source inside a NIA lab and again the corona detection alerts successfully sounded.
Next, the UV source was turned off and the UAV was flown to test the reliability of the UV detection: when the UAV passed the inactive UV source, no alerts were signaled. The UAV needed to be tested with the UV source turned off to make sure that the photosensors did not trigger an alert. Since it did not, it was reasonable to assume the system was responding only to the presence of UV.
Finally, the UV source was turned back on and the UAV was flown by the UV source a final time. Again, the UV alarms went off as the sensors detected the corona, verifying that the system will respond only to potential power line problems.
Drones provide a safer way to detect power line problems by reducing the amount of time utility workers spend at great heights, a faster way to find and repair faults, and a cheaper way to ensure that your home is always powered.
- Charlotte, NC and Hampton VA, USA July 2015
Special thanks to:
Fabio Bologna, Electric Power Research Institute
Andrew Phillips, Electric Power Research Institute
Sharon Graves, NASA LaRC
Kathryn Guild, Media Solutions Branch, NASA LaRC and Genex Systems
Charles Hatfield, Media Solutions Branch, NASA LaRC and Genex Systems
