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An exact analytical expression for the electric field of the return stroke as excited by a propagating step current source is derived in this paper. This expression could be advantageously used to evaluate the disturbances caused by lightning on overhead l ...
This paper proposes a tower-foot grounding system model compatible with EMT programs which might be useful for the simulation of lightning transients in overhead lines. The proposed model is based on the solution of the telegrapher's equations and the appl ...
Lightning discharges, including cloud-to-ground (CG) and intracloud (IC) lightning, are known to emit electromagnetic pulses (EMPs) in a wide frequency band ranging from few Hz up to hundreds MHz [1]. During the breakdown and ionization processes (mostly f ...
The evaluation of lightning ElectroMagnetic (EM) fields represents the most cumbersome part of the lightning-induced voltages computation process. Their evaluation is usually performed through a numerical routine or with simplified analytical expressions, ...
The article provides analytical expressions for the electromagnetic fields generated by a lightning return stroke characterized by a channel-base current with arbitrary time waveform, in presence of either a perfectly conducting or a lossy ground, assuming ...
A current generation type return stroke model which can take into account the possible modifications of the return stroke properties by the soil conductivity at the strike point of the lightning flash is introduced. The model is also capable of incorporati ...
This paper investigates the impact of incorporating both displacement currents and frequency-dependent soil parameters in the calculation of the ground-return impedance for the determination of the backflashover rate of 138 kV and 230 kV overhead transmiss ...
In this chapter, we discussed the TL theory and its application to the problem of lightning electromagnetic field coupling to transmission lines. After a short discussion on the underlying assumptions of the TL theory, we described seemingly different but ...
A correct representation of the lightning current is crucial when the electromagnetic field radiated to a point of interest has to be computed. Based on the engineering models of Transmission Line type, such representation involves the knowledge of the ret ...
This paper investigates the effect of frequency-dependent soil parameters on the simulation of electromagnetic transients on overhead lines, based on the application of the FDTD method to solve the telegrapher’s equations. The ground return impedance is ca ...
