@inproceedings{ZischankHeidlerKernetal.2002, author = {Zischank, Wolfgang J. and Heidler, Fridolin and Kern, Alexander and Metwally, I. A. and Wiesinger, J. and Seevers, M.}, title = {Laboratory simulation of direct lightning strokes to a modelled building - measurement of magnetic fields and induced voltages}, year = {2002}, abstract = {In IEC 61312-2 equations for the assessment of the magnetic fields inside structures due to a direct lightning strike are given. These equations are based on computer simulations for shields consisting of a single-layer steel grid of a given mesh width. Real constructions, however, contain at least two layers of reinforcement steel grids. The objective of this study was to experimentally determine the additional shielding effectiveness of a second reinforcement layer compared to a single-layer grid. To this end, simulated structures were set up in the high current laboratory. The structures consisted of cubic cages of 2 m side length with one or with two reinforcement grids, respectively. The structures were exposed to direct lightning currents representing the variety of anticipated lightning current waveforms. The magnetic fields and their derivatives at several positions inside the structure as well as the voltage between "floor" and "roof" in the center were determined for different current injection points. From these data the improvement of the shielding caused by a second reinforcement layer is derived.}, language = {en} } @article{KernHeidlerZischanketal.2002, author = {Kern, Alexander and Heidler, Fridolin and Zischank, Wolfgang J. and Frentzel, Ralf}, title = {Lightning current distribution and coupling to control cables in power plants or large industrial facilites}, year = {2002}, language = {en} } @article{KernKrichelNeskakisetal.2001, author = {Kern, Alexander and Krichel, Frank and Neskakis, Apostolos and M{\"u}ller, Klaus-Peter (u.a.)}, title = {Lightning protection design of a renewable energy hybrid-system without power mains connection}, year = {2001}, language = {en} } @inproceedings{KernKrichelMueller2001, author = {Kern, Alexander and Krichel, Frank and M{\"u}ller, Klaus-Peter}, title = {Lightning protection design of a renewable energy hybrid-system without power mains connection}, year = {2001}, abstract = {In the year 2000 a direct lightning strike to the hybridsystem without power mains connection VATALI on the Greek island Crete results in the destruction and damage of some mechanical and electrical components. The hybrid-system VATALI was not lightning protected at that time. The hardware damage costs are approx. 60,000 €. The exposed site of the hybrid-system on top of a mountain was and still is the reason for a high risk of lightning strikes. Also in the future further lightning strikes have to be taken into consideration. In the paper a fundamental lightning protection design concept for renewable energy hybrid-systems without power mains connection and protection measures against direct strikes and overvoltages are shown in detail. The design concept was realized exemplarily for the hybrid-system VATALI. The hardware costs for the protection measures were about 15,000 €. About 50\% of the costs are due to protection measures against direct strikes, 50\% are due to overvoltage protection. Future extensions, new installations, or modifications have to be included into the lightning protection design concept of the hybrid-system.}, language = {en} } @article{BouquegneauKernRousseau2010, author = {Bouquegneau, Christian and Kern, Alexander and Rousseau, Alain}, title = {Lightning safety guidelines}, pages = {1 -- 6}, year = {2010}, language = {en} } @article{KernZischank1993, author = {Kern, Alexander and Zischank, Wolfgang J.}, title = {L{\"a}ngsspannung an blitzstromdurchflossenen Schirmkabeln - Einfluß paralleler Entlastungsleitungen}, series = {Elektrie : wissenschaftlich-technische Zeitschrift der Elektrotechnik. 47 (1993), H. 6}, journal = {Elektrie : wissenschaftlich-technische Zeitschrift der Elektrotechnik. 47 (1993), H. 6}, isbn = {0013-5399}, year = {1993}, language = {de} } @inproceedings{KernHeidlerSeeversetal.2004, author = {Kern, Alexander and Heidler, Fridolin and Seevers, M. and Zischank, Wolfgang J.}, title = {Magnetic Fields and Induced Voltages in case of a Direct Strike - Comparison of Results obtained from Measurements at a Scaled Building to those of IEC 62305-4}, isbn = {0304-3886}, year = {2004}, abstract = {In the paper the results obtained from experiments at a modelled reinforced building in case of a direct lightning strike are compared with calculations. The comparison includes peak values of the magnetic field Hmax, its derivative (dH/dt)max and of induced voltages umax in typical cable routings. The experiments are performed at a 1:6 scaled building and the results are extrapolated using the similarity relations theory. The calculations are based on the approximate formulae given in IEC 62305-4 and have to be supplemented by a rough estimation of the additional shielding effect of a second reinforcement layer. The comparison shows, that the measured peak values of the magnetic field and its derivative are mostly lower than the calculated. The induced voltages are in good agreement. Hence, calculations of the induced voltages based on IEC 62305-4 are a good method for lightning protection studies of buildings, where the reinforcement is used as a grid-like electromagnetic shield.}, subject = {Blitz}, language = {en} } @inproceedings{ZischankHeidlerWiesingeretal.2004, author = {Zischank, Wolfgang J. and Heidler, Fridolin and Wiesinger, J. and Stimper, K. and Kern, Alexander and Seevers, M.}, title = {Magnetic Fields and Induced Voltages inside LPZ 1 Measured at a 1:6 Scale Model Building}, year = {2004}, abstract = {Laborexperimente zu Blitzschutzzonen in Stahlbetongeb{\"a}uden anhand eines Modells im Maßstab 1:6}, language = {en} } @article{KernZischank1988, author = {Kern, Alexander and Zischank, Wolfgang J.}, title = {Melting effects on metal sheets and air termination wires caused by direct lightning strikes}, series = {Conference proceedings : Graz, {\"O}sterreich, 25. - 29. April 1988 / Gesamtorganisation: {\"O}sterr. Verb. f{\"u}r Elektrotechnik ({\"O}VE), Fachausschuß Blitzschutz ... [Red.: G. Diendorfer ...]}, journal = {Conference proceedings : Graz, {\"O}sterreich, 25. - 29. April 1988 / Gesamtorganisation: {\"O}sterr. Verb. f{\"u}r Elektrotechnik ({\"O}VE), Fachausschuß Blitzschutz ... [Red.: G. Diendorfer ...]}, publisher = {Eigenverl. des {\"O}VE}, address = {Wien}, isbn = {3-85133-001-3}, year = {1988}, language = {en} } @article{Kern2007, author = {Kern, Alexander}, title = {Neue deutsche Blitzschutz-Normung. Reihe DIN EN 62305 / VDE 01 85-305-x:2006}, series = {Der Eisenbahningenieur. 58 (2007), H. 8}, journal = {Der Eisenbahningenieur. 58 (2007), H. 8}, isbn = {0013-2810}, pages = {18 -- 22}, year = {2007}, language = {de} } @inproceedings{KernMeppelink2001, author = {Kern, Alexander and Meppelink, Jan}, title = {Neue M{\"o}glichkeiten elektrischer Anschl{\"u}sse an die Bewehrung und Untersuchung der Wirkung von Blitzstr{\"o}men in bewehrtem Beton}, year = {2001}, abstract = {Im Rahmen eines modernen Blitzschutzsystems f{\"u}r Stahlbeton-Bauten bietet es sich an, die Betonbewehrung zu benutzen: - Sie kann die Funktionen der Ableitungseinrichtungen und des Blitzschutz- Potentialausgleichs bei einem klassischen Geb{\"a}ude-Blitzschutz {\"u}bernehmen [1]; - Sie kann, ggf. bei entsprechender Erg{\"a}nzung, als ein geschlossener K{\"a}fig ausgebildet werden und damit eine deutliche Reduzierung der Belastung elektrischer / elektronischer Systeme durch blitzinduzierte elektromagnetische Felder erbringen (LEMP-Schutz [2]). Die Nutzung der Bewehrung ist dabei grunds{\"a}tzlich gleichermaßen bei Neubauten wie auch bei Ert{\"u}chtigungen m{\"o}glich und sinnvoll. So stellt die Nutzung der Bewehrung beispielsweise im Bereich von Großkraftwerken eine wesentliche Ert{\"u}chtigungsmaßnahme f{\"u}r den Blitzschutz elektrischer und elektronischer Einrichtungen dar: - Einerseits wird der Blitzschutz-Potentialausgleich durch den Anschluss metallener Einrichtungen wie Elektronik-Schr{\"a}nke, Kabeltrag-Konstruktionen, Rohrleitungen, etc. an die Bewehrung deutlich verbessert. - Andererseits kann bei gr{\"o}ßeren Geb{\"a}uden die elektromagnetische Schirmwirkung durch die elektrische {\"U}berbr{\"u}ckung von vorhandenen Dehnfugen bei Stahlbetonbauten optimiert werden. Diese Dehnfugen sind teilweise nur unzureichend {\"u}berbr{\"u}ckt, so dass bei Blitzeinschlag in das betreffende oder ein benachbartes Geb{\"a}ude an Kabelstrecken, die {\"u}ber die Dehnfuge hinwegf{\"u}hren, rel. hohe Spannungen induziert werden k{\"o}nnen [2, 3]. Die sich um das gesamte Geb{\"a}ude herumziehende oder zwischen zwei Geb{\"a}uden befindliche Dehnfuge muss deshalb im Abstand von maximal einigen Metern {\"u}berbr{\"u}ckt werden. Im Falle von Blitzschutz-Ert{\"u}chtigungen in vorhandenen Geb{\"a}uden wird bisher an jeder geplanten Anschlussstelle die Bewehrung großfl{\"a}chig (\&\#8709; wenige 10 cm) freigelegt, dort ein elektrischer Anschluss zu dem Bewehrungsstab hergestellt, z.B. mittels eines Erdungsfestpunkts, und dann die Betonoberfl{\"a}che wieder geschlossen. Je nach prognostizierter Strombelastung wird teilweise versucht, den {\"u}ber den Anschluss fließenden Strom bereits auf mehrere Bewehrungsst{\"a}be zu verteilen. Dazu sind entweder die kreuzenden St{\"a}be zu verschweißen oder es sind direkt Anschl{\"u}sse an zwei Bewehrungsst{\"a}be herzustellen. All dieses bedeutet einen hohen Aufwand bei der Freilegung der Bewehrung und auch wieder bei der Schließung der entstandenen Betonl{\"o}cher. Es soll deshalb hier untersucht werden, ob es beispielsweise zum Zwecke des Blitzschutz-Potentialausgleichs und auch zur {\"U}berbr{\"u}ckung von Dehnfugen ausreichend ist, den Anschluss an die Bewehrung nach einfachen Verfahren nur jeweils an einen Bewehrungsstab herzustellen. Damit w{\"u}rde der finanzielle und administrative Aufwand an Betonarbeiten deutlich reduziert. Die hier dargestellten Verfahren sind dabei insbesondere f{\"u}r den Einsatz bei Blitzschutz-Ert{\"u}chtigungen in bestehenden Geb{\"a}uden vorgesehen. Abschließend sollen deshalb die M{\"o}glichkeiten zur Pr{\"u}fung korrekter Anschl{\"u}sse, die Grenzen der Verfahren sowie auch die Grenzen der Anwendbarkeit bei Neuanlagen diskutiert werden.}, language = {de} } @article{KernBraun2013, author = {Kern, Alexander and Braun, Christian}, title = {Neuerungen bei der Blitzschutznorm. Teil 2}, series = {etz Elektrotechnik und Automation}, volume = {Bd. 134}, journal = {etz Elektrotechnik und Automation}, number = {H. 8}, publisher = {VDE-Verlag}, address = {Wuppertal}, issn = {0170-1711}, pages = {66 -- 69}, year = {2013}, language = {de} } @inproceedings{WetterKern2014, author = {Wetter, Martin and Kern, Alexander}, title = {Number of lightning strikes to tall structures - comparison of calculations and measurements using a modern lightning monitoring system}, series = {2014 International Conference on Lightning Protection (ICLP), Shanghai, China}, booktitle = {2014 International Conference on Lightning Protection (ICLP), Shanghai, China}, organization = {International Conference on Lightning Protection <2014, Shanghai>}, pages = {1 -- 7}, year = {2014}, language = {en} } @inproceedings{Kern2017, author = {Kern, Alexander}, title = {Optimierung des Blitzschutzes bei Biogasanlagen}, series = {12. VDE/ABB-Blitzschutztagung : Beitr{\"a}ge der 12. VDE/ABB-Fachtagung, 12.-13. Oktober 2017, Aschaffenburg}, booktitle = {12. VDE/ABB-Blitzschutztagung : Beitr{\"a}ge der 12. VDE/ABB-Fachtagung, 12.-13. Oktober 2017, Aschaffenburg}, isbn = {978-3-8007-4459-6}, pages = {48 -- 56}, year = {2017}, language = {de} } @article{KernKloetersPferdemenges2010, author = {Kern, Alexander and Kl{\"o}ters, Georg and Pferdemenges, J{\"o}rg}, title = {Optimised protection against lightning for the signalling and safety systems of level crossings on non-electrified railway lines}, series = {RTR : European Rail Technology Review}, volume = {50}, journal = {RTR : European Rail Technology Review}, number = {2}, isbn = {0079-9548}, year = {2010}, language = {en} } @article{Kern1993, author = {Kern, Alexander}, title = {Physik der Blitzentladung und Blitzstrom-Parameter bei nat{\"u}rlichen Blitzen}, year = {1993}, language = {de} } @inproceedings{KernBrocke2017, author = {Kern, Alexander and Brocke, Ralph}, title = {Planung von Fangeinrichtungen mit dem dynamischen elektro-geometrischen Modell - M{\"o}gliche praktische Anwendungen}, series = {12. VDE/ABB-Blitzschutztagung : Beitr{\"a}ge der 12. VDE/ABB-Fachtagung, 12.-13. Oktober 2017, Aschaffenburg}, booktitle = {12. VDE/ABB-Blitzschutztagung : Beitr{\"a}ge der 12. VDE/ABB-Fachtagung, 12.-13. Oktober 2017, Aschaffenburg}, isbn = {978-3-8007-4459-6}, pages = {75 -- 82}, year = {2017}, language = {de} } @inproceedings{KernDikta2009, author = {Kern, Alexander and Dikta, Gerhard}, title = {Probability of damage of electrical and electronic systems due to indirect lightning flashes - investigation of data from German insurance companies}, year = {2009}, abstract = {In the presented paper data collected from the field related to damage statistics of electrical and electronic apparatus in household are reported and investigated. These damages (total number approx. 74000 cases), registered by five German insurance companies in 2005 and 2006, were adviced by customers as caused by lightning overvoltages. With the use of stochastical methods it is possible, to reasses the collected data and to distinguish between cases, which are with high probability caused by lightning overvoltages, and those, which are not. If there was an indication for a direct strike, this case was excluded, so the focus was only on indirect lightning flashes, i.e. only flashes to ground near the structure and flashes to or nearby an incoming service line were investigated. The data from the field contain the location of damaged apparatus (residence of the policy holder) and the distances of the nearest cloud-to-ground stroke to the location of the damage registered by the German lightning location network BLIDS at the date of damage. The statistical data along with some complementary numerical simulations allow to verify the correspondence of the Standards rules used for IEC 62305-2 with the field data and to define some correction needs. The results could lead to a better understanding whether a damage reported to an insurance company is really caused by indirect lightning, or not.}, subject = {Blitzschutz}, language = {en} } @article{KernSchelthoffMathieu2010, author = {Kern, Alexander and Schelthoff, Christof and Mathieu, Moritz}, title = {Probability of lightning strikes to air-terminations of structures using the electro-geometrical model theory and the statistics of lightning current parameters}, pages = {750-1 -- 750-8}, year = {2010}, language = {en} } @article{KernSchelthoffMathieu2011, author = {Kern, Alexander and Schelthoff, Christof and Mathieu, Moritz}, title = {Probability of lightning strikes to air-terminations of structures using the electro-geometrical model theory and the statistics of lightning current parameters}, series = {Atmospheric Research. 104 (2011)}, journal = {Atmospheric Research. 104 (2011)}, publisher = {Elsevier}, address = {Amsterdam}, isbn = {0169-8095}, year = {2011}, language = {en} }