A wave-front-time dependent corona model for transmission-line surge calculations

Abstract

For transmission‐line surge studies, the inclusion of corona discharge due to high voltage surges is important as well as the inclusion of frequency‐dependent effects. Because the charge‐voltage (q‐v) curve of a lightning surge is different from that of a switching surge, a corona model should reproduce different q‐v curves for different wave‐front times. The present paper proposes a wave‐front time dependent corona model which can express the dependence by a simple calculation procedure as accurately as a rigorous finite‐difference method which requires an enormous calculation time. The simplicity enhances the incorporation of the corona model into a line model, because a large number of models are to be inserted into the line model by discretization. The q‐v curves calculated by the proposed method agrees well with field tests. This paper also proposes an efficient method to deal with nonlinear corona branches in distributed‐parameter line model using the trapezoidal rule of integration and the predictor‐corrector method. © 1999 Scripta Technica, Electr Eng Jpn, 129(1): 29–38, 1999

A study on the influence of corona on currents and electromagnetic fields predicted by a nonlinear lightning return‐stroke model

“…Many different models are available in the literature for simulating corona in transmission lines [e.g., Wagner and Lloyd , ; Gary et al , ; Carneiro and Marti , ; Noda et al , ; Thang et al , , ]. Here the propagation of the return‐stroke current in a lossy transmission line in the presence of corona is solved numerically by applying the first‐order finite difference time domain technique described by Paul [] to the transmission line equations ∂ v /∂ x + Ri + L ∂ i /∂ t = 0 and ∂ i /∂ x + C ∂ v /∂ t = − i c , where i c accounts for the corona currents leaving the channel due to the return stroke as proposed by Cooray and Theethayi [].…”

Charge-voltage curves of surge corona on transmission lines: two measurement methods

“…Thus, the amount of charges per unit length is (4) The propagation velocity and the surge impedance are modified by the progress of corona as follows [1]. where is the inductance; is the capacitance; and is the increase of by corona, all per unit length (see Appendix B).…”

“…This shape may be considered as the typical shape of -curves. The measured -curves by method I were simulated by a wave-steepness-dependent corona model [4], [5], and the result is shown in Fig. 15.…”

“…Those two methods were validated by field tests, and the results are presented. This paper also includes the simulation of the measured -curves using a wave-steepness-dependent corona model [4], [5]. Fig.…”

Attenuation and deformation characteristics of lightning impulse corona traveling along bundled transmission lines

“…Many researchers have studied the physics and discharge process of impulse corona [6][7][8]. In 1954, Wagner and Lloyd firstly carried out impulse corona experiments on an outdoor overhead line and measured the deformed voltage waveform [9].…”