Volume, Issue, Month, Year : Vol (1), No (1), September, 2016
Lightning protection and insulation coordination of transmission lines and substations require an accurate knowledge of the magnitudes and waveforms of lightning overvoltage. To simulate the lightning overvoltage precisely near the substation, this study has shown how to consider the lightning impulse corona for distortion effect of this overvoltage. Attenuation and deformation effects of lightning impulse corona along transmission lines are evaluated by the simulation results. This paper describes the substation equipment modeling in the software Electromagnetic Transients Program–Alternative Transients Program EMTP. Corona effect is incorporate in order to estimate the attenuation and deformation of overvoltage’s travelling waves on transmission lines near substations. Variations of lightning stroke current magnitudes, protection distances, and the impact points are obvious due to the applied dynamic corona model. Several elements of substation equipment are modeled in ATP/EMTP using MODELS language. The Simulation results show that the amplitude and voltage travelling wave-fronts attenuated remarkably. Deformation of the wave shapes mainly occurs when the impulse voltage exceeds the corona inception voltage.