Improvement of a Magnetic Direction-Finder Network in the Tohoku District

Abstract

Tohoku Electric Power Company constructed an LLP-system that covered Tohoku District with 9 magnetic direction finders (DFs). This system is capable of locating flashes with current exceeding 10 kA in good location accuracy, throughout the coverage area. The successful operation of this new system was achieved through the modification of waveform discrimination criteria to improve detection efficiency, and through the optimum arrangement of the DFs, together with the evaluation of site error at each DF.
Based on the analysis of the data obtained so far, operational characteristics of the system and some factors which affect the performance of the system have been revealed.