Abstract:
Background High-altitude electromagnetic pulse E1 (HEMP E1) can induce transient voltages and currents on transmission lines. Existing time-domain field-to-line coupling methods incur high computational costs when lossy-ground effects are taken into account.
Purpose This study proposes a rapid HEMP E1 field-to-line coupling method applicable to ground effects, non-analytical excitation waveforms, and nonlinear terminal loads.
Methods Based on plane-wave propagation, the total electric field at a reference point at the transmission-line height is obtained in the frequency domain by superimposing the incident and ground-reflected fields and then transformed into the time domain using inverse Fourier transform. Excitations at other spatial nodes are reconstructed via time shifting and linear interpolation and incorporated into the finite-difference time-domain discretized transmission-line equations to calculate the transient coupling response.
Results Under both perfect electric conductor (PEC) and lossy-ground conditions, the calculated coupling-voltage waveforms, peak values, and oscillatory characteristics agree well with those obtained using the one-dimensional finite-difference time-domain, Runge–Kutta, transmission-line, and Baum–Liu–Tesche methods. The proposed method requires field evaluation at only a single reference point, avoiding repeated calculations along the line. It is also applicable to numerically obtained HEMP E1 waveforms and nonlinear-load voltage-limiting analysis.
Conclusions The proposed method improves the efficiency of time-domain HEMP E1 field-to-line coupling analysis while maintaining accuracy and extends its applicability to lossy-ground environments, non-analytical excitations, and nonlinear loads.
下载: