Development of a new model to represent polyphasic transmission lines in Electromagnetic Transients Programs (EMT)

Abstract

This research project is presented by Thassio Matias Pereira, a regular master student of the Graduate Program of the Faculty of Electrical Engineering of the State University of Campinas (UNICAMP), with the Department of Energy Systems, under the guidance of Professor PhD. Maria Cristina Dias Tavares. The research project consists in the development of a new model to represent polyphase transmission lines in Electromagnetic Transients Programs (EMT), which will allow the representation of the corona effect and frequency dependence of the line parameters. The corona effect is a phenomenon commonly observed during overvoltages in overhead transmission lines, and occurs when the electric field on the conductor's surface exceeds the critical disruptive voltage of air. This phenomenon plays a predominant role in the attenuation and distortion of traveling waves, which makes his adequately representation digital simulations extremely important to obtain accurate and reliable results. Under these circumstances, this research will focus on the development of a new line model applicable to EMT programs, which will capable to represent the wave propagation phenomenon, the frequency dependence of line parameters and the corona effect directly in the line equations. In addition, this model will allow the corona effect to be represented as a distributed parameter, and will represent with good accuraccy the variations in capacitive coupling between phases when the line is under corona. (AU)