A multi-conductor transmission lines-based approach is developed to model electromagnetic coupling of wires above metallic structures. With this approach, global impedances and local distributions are accessible. According the frequency range and the geometry of the studied structures, it is possible to only take into account well-chosen parts. In that case, the shading concept provides an efficient way to determine which part is sufficient, thereby allowing reduction in model size. Global quantities results are validated against measurements, and local ones by theoretical knowledge. This work is usefulness in both the nomadic applications (automotive and aeronautic wiring . . . ) and the usual electrical applications (home and industrial wiring).Key words: Electromagnetic coupling, ground planes, Shade of conductors, transmission line modeling (MTL.), wiringElektromagnetsko modeliranje struktura žica-uzemljenje korištenjem pristupa temeljenog na modeliranju transmisijskih linija. Pristup temeljen na visevodičkim transmisijskim linijama razvijen je kako bi se modelirala elektromagnetska sprega žica iznad metalnih struktura. Uz takav pristup, dostupne su i globalne impedancije i lokalne distribucije. S obzirom na raspon frekvencija i geometriju promatranih struktura moguće je uzeti u obzir samo dobro odabrane dijelove. U tom slučaju koncept zasjenjenja pruža učinkovit način za odreivanje koji su dijelovi dostatni i tako se omogućuje smanjenje veličine modela. Rezultati globalnih veličina vrednovani su prema mjerenjima, a lokalne veličine prema teoretskom znanju. Ovaj je rad koristan u specifičnim aplikacijama (automobilsko i aeronautičko ožičenje . . . ) i klasičnim električnim aplikacijama (kućanstvo i industrija).

In automotive wiring application EM problems are often characterized by a wide span of ratio between geometrical size and signals wavelength. This is a critical situation for conventional numerical simulation tools. This paper proposes an efficient technique to overcome the difficulty of the wiring simulation on large vehicle chassis by reducing them. Using the MTL method and based on the electromagnetic shade of a cable to a ground plane, the area where currents distribution is concentrated is identified. Several geometrical configurations are studied with one or multiple grounds planes to evaluate the advantages in term of simulation costs (time and memory).