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Lightning return stroke and its modeling

In this chapter, we give an overview of lightning discharges, which can cause electromagnetically induced effects in power and telecommunication systems. Then, we describe modeling of the lightning return stroke and explain “engineering” models, in which the spatial and temporal distribution of the current or the line charge density along the lightning channel is specified based on such observed lightning return-stroke characteristics as current at the channel base, the speed of the upward-propagating front, and the channel luminosity profile. Also, we discuss the equivalency between the lumped-source and distributed source representations, and the extension of engineering models to include a tall grounded strike object. Further, we describe two primary approaches to test lightning return-stroke models that are referred to as “typical-event” and “individual-event” approaches.