Analysis of electromagnetic transitory in transmission lines using implicit methods

• Grant number: 18/05305-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2019
• End date: December 31, 2019
• Field of knowledge: Engineering - Electrical Engineering - Telecommunications
• Principal Investigator: Afonso José do Prado
• Grantee: Caio Cesar Souza de Luca
• Host Institution: Universidade Estadual Paulista (UNESP). Campus Experimental São João da Boa Vista. São João da Boa Vista , SP, Brazil

Abstract

This research project has as proposal a work in the area of transient electromagnetic phenomena in electrical networks with a main focus on transmission lines, both for power transmission and for signal transmission. The transmission line theory can be applied in both low frequency and low frequency power supply systems, which is performed at high frequency. Therefore, the proposed work aims to improve numerical modeling that can be used in these two types of transmission systems. This work will use numerical tools and digital models that allow the analysis of the effects of electromagnetic transients on transmission lines. Using numerical modeling developed previously and based on explicit methods of numerical integration, the application of an implicit method of numerical integration in the modeling of transmission lines to simulate the propagation of transient electromagnetic phenomena in this type of electric system will be analyzed. It is important to note that in the case of power systems, it is impracticable to perform tests on real transmission lines. In the case of data transmission systems, it is often necessary to simulate the propagation of transients before the systems are physically constructed. That is, this should be done based on numerical models, mainly. The proposed work can be divided into two main blocks. Initially, the mathematical modeling of transmission lines using À circuits will be studied. These circuits are composed, in their classical form, by concentrated, constant and frequency independent elements. Generally, even three-phase systems are represented by equivalent single-phase cascades of À circuits. These cascades are applied in the composition of state equations whose state variables are the voltages and currents of each circuit À. The use of constant parameters in the representation of the line in all the frequency bands can result in incoherent responses to the reality and, therefore, transmission line models consider the influence of the frequency on the line parameters. In this work, the influence of frequency will not be considered in the initial stages, because the research will be focused on the advantages and disadvantages of the alteration of the integration method used. That is, the comparisons between the methods used will be more effective if the classical circuit structure À is used.