Hepta Airborne scanned kilometres of overhead power lines – infrastructure inspection digitiser – to detect defects, which project partner Järvi-Suomen Energia created by felling trees on the lines to mimic the storm damage that occurs during heavy winds.
LiDAR detection speeds up locating and eliminating damage on overhead powerlines during storms and low-light situations. The project results will help shorten electricity outages and improve power service for homeowners in Finland’s lake district and other challenging terrain areas in the Nordics and elsewhere.
Power outages on middle voltage grids cause thousands of people to lose electricity in their homes during the coldest and darkest time of the year. Difficult terrain and limited daylight make finding and eliminating damage on power lines a challenge for DSOs. Worldwide, the most prevalent method for locating fallen trees on power lines is on foot, skis, or ATVs, which is time-consuming and poses real threats to the inspection team’s safety.
To minimise the distance covered on foot by ground teams, typically, RGB sensor-utilising drones are used to capture high-resolution photos of the damages. While drones make it possible to cover distances quickly and fly 24/7, the cameras are not sufficient to detect grid damage in low-light situations. An efficient way to overcome the limitations of low light is to use LiDAR sensors to capture data day and night.
Hepta Airborne’s CEO Henri Klemmer commented: “Deploying LiDAR-equipped drones can significantly improve the efficiency of eliminating grid faults and restoring DSO service during power outages in stormy seasons, especially in areas of challenging terrain with limited daylight in the Nordics. Moreover, LiDAR inspection has a much wider application range, being an exceptional match to any occasion that requires speed in data collection and analysis.”
The tests were conducted on an old overhead power line that was to be replaced by underground electricity cables, 3 km in total, in the most storm damage-prone area. In total, 20 trees were felled on the power lines by the JSE ground team to cause significant damage – broken lines and insulators, and severely tilted poles.
Hepta Airborne performed several flights with different LiDAR-equipped industrial drones at various altitudes and speeds to find the optimal flight parameters for different types of storm damage. The gathered data provided input for ESRI Finland to develop an algorithm that can detect the entirety of any damage and report instantly.
Tomi Öster, the Business Development Manager at Järvi-Suomen Energia, commented: “This type of data gathering and analytics is key to benefit from drones on a large scale and put such fast response into operational use. Future plans regarding this inspection method are to get operational benefits next autumn to detect different kinds of disturbances and snow loads during low pressure and thunderstorms.”