Electromagnetic Transient Analysis of Overhead Lines Including Corona and Frequency-Dependence Effects Under Damped Oscillation Surges

An efficient method is proposed for predicting the attenuation and distortion of the damped oscillation surges traveling on single-phase overhead lines under the influence of corona and frequency dependence of line parameters. The finite-difference time-domain algorithm is employed in the transient computation. The Suliciu's corona model is extended to simulate the charge-voltage curves with minor loops under the damped oscillation surges. The corona effect is considered by adding a corona current term in the telegraphers' equations. The frequency-dependence effect is also taken into account by using the vector fitting and recursive convolution in the time domain. The computed voltage waveforms are compared with the measured ones to examine the validity of the proposed method. The computed results show that the minor loops have a greater effect on the attenuation and distortion for the damped oscillation surges under negative polarity.