Mots-clé
(Anglais)
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Lightning; measurements
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Programme de recherche
(Anglais)
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COST-Action P18 - The Physics of Lightning Flash and Its Effects
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Description succincte
(Anglais)
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The telecommunications tower on the Säntis near Saint Gallen is struck by lightning over 400 times a year. We propose to instrument that tower to gather important data on lightning currents and fields that will help enlarge our measurement database and improve our understanding of the lightning phenomenon. The proposed measurement system will be comprised of current sensors, electric and magnetic field sensors and a storm detection sensor. As an integral part of the sensor system, we will design, build, test and install a robust remote maintenance, monitoring, calibration, and control system to manage the operation, power supply and data storage and data transfer of the measurement sensors themselves. Such a remote system is vital, given the difficulty in maintaining permanent scientific personnel presence at the site due to the inauspicious weather conditions that the site is subjected to, especially during the winter months. The system will be tested under real conditions during the Summer 2009 lightning season.
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Autres indications
(Anglais)
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Full name of research-institution/enterprise: Haute Ecole Spécialisée, HES-SO Ecole d'Ingénieurs du Canton de Vaud (EIVD) Route de Cheseaux 1
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Partenaires et organisations internationales
(Anglais)
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AT, BE, BG, CH, CY, DE, DK, ES, FI, FR, HU, IL, IT, MK, NL, PL, PT, RS, SE, SI, UK
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Résumé des résultats (Abstract)
(Anglais)
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The Säntis tower near Saint Gallen is struck by lightning several hundred times a year, making it ideal for the gathering of important data on lightning currents and fields that can help improve our knowledge of the lightning phenomenon and its effects. As part of this project, we designed and built in cooperation with the EPFL a lightning current measurement system comprised of two types of current sensors, Rogowski coils, to measure the slower parts of the lightning currents such as the initial continuing current that allow us to distinguish between upward and downward initiated lightning to the tower, and B dot sensors to record the derivative of the magnetic fields close next to the tower and, from it, to derive the faster features of the current waveforms. To avoid having to maintain a presence on the site (which can be often diffcult to reach due to rough weather and distance), an over-the-Internet remote control and monitoring system was also desinged and built to contrôl de temperature, manage the operation, power supply, data storage and data transfer of the measurement sensors. Testing of the system in the laboratory showed that the basic operation of the sensors, data transmission, control and monitoring subsystems work well, although unexpected problems with a relay and with commercial integrators used in conjunction with the Rogowski coils lead to a delay in the installation, which was finally carried out on May 28th 2010. Although the EMC boxes containing the processing and transmission electronics on the tower exhibited at first a problem that shut them off due to insufficient filtering of the power supply, the tests under real conditions allowed us to record a first lightning on June 22nd. The problems have now been solved and more than 40 lightning flashes have been recorded, which represents a great success, especially considering the fact that other towers in Germany and Austria have been struck by lightning very seldom during this time period.
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Références bases de données
(Anglais)
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Swiss Database: COST-DB of the State Secretariat for Education and Research Hallwylstrasse 4 CH-3003 Berne, Switzerland Tel. +41 31 322 74 82 Swiss Project-Number: C07.0037
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