Transient Electromagnetic Field Emitted by a Pulsed Current Travelling alongFinite, Thin Straight Wires above a Plane Non-Perfectly Conducting Earth

摘要

The transient electromagnetic field emitted by a pulsed current travelling alonga configuration of thin, straight wires above a plane non-perfectly conducting earth is investigated. This problem is of great interest in the field of electromagnetic interfering problems (EMC). These problems occur in the vicinity of high voltage distribution lines, due to the switching phenomena, large current impulses can cause large transient voltages coupled to control and signal circuits. By using proper transformation variables in the Laplace-Fourier-transform domain the authors can solve with the aid of the Cagniard-de Hoop method the transient electromagnetic field emitted by a pulsed current travelling along an arbitrarily oriented configuration of thin, straight wires above a plane non-perfectly conducting earth. To increase the numerical efficiency in the case of a lossy half-space the authors have next to the exact expression incorporated two approximate expressions based on the Tauberian theorems for the reflection coefficient by expanding them in a Taylor series for the time-Laplace variable s around s --> infinity (early-time approximation) and s --> 0 (late-time approximation). (Copyright (c) 1995 Laboratory of Electromagnetic Research.)