Lightning strike location for overhead lines

The author has developed a lightning strike location system which uses radio direction finding techniques to locate lightning strikes as they occur on overhead power lines. The system has been operated as a commercial service since 1989, providing both online information and historical information on lightning activity in the UK and Ireland. The direction finding antenna are highly sensitive and are able to detect strikes with a current as low as 3 kA at a distance of 1000 km. Lightning stroke data recorded at each outstation is time-tagged and transmitted to a central system. Here it is analysed to determine the position, strength, polarity and time of the stroke. All data is stored locally and stroke information is also transmitted in real-time to customers of the online service. The system can handle 100 strokes per second. Remote displays are typically updated within less than a second of the stroke occurring