Corona modeling for lightning overvoltages studies in overhead transmission lines

Author(s)

Thassio Matias Pereira

• Document type: Master's Dissertation
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia Elétrica e de Computação
• Defense date: 2019-11-29

Examining board members

Maria Cristina Dias Tavares; Alberto Resende De Conti; Rafael Silva Alípio

• Advisor: Maria Cristina Dias Tavares

Abstract

This work presents a study about modeling and representation of the corona effect in electromagnetic transient programs (EMT), which the focus is on the representation of the at-tenuations and distortions caused by this phenomenon in the occurrence of lightning overvolt-ages. In summary, the content covered can be divided into two parts: In the first part we evaluate the performance and accuracy of several corona effect models developed over the years by different researchers. The analyzed models were imple-mented in the PSCAD program, where several simulations were performed and the obtained results were compared with field measurement data. In this stage, the procedures necessary to implement the models were also described, as well as the main advantages and disadvantages of each one. In the second part a new methodology for the representation of the corona effect in transmission lines is presented. Based on the method of characteristics and the scheme pro-posed by H. Dommel for representation of distributed parameters lines in EMT-type programs, a voltage-dependent line model (VDLM) was developed. This model can be represented through of an equivalent impedance network, which makes it suitable for applications in EMT programs and allows easy combination with other components of the electrical power system. For performance evaluation, the proposed model was implemented in the Matlab software and the simulation's results were compared with field measurements to verify its accuracy. Good agreement could be observed between them (AU)

• FAPESP's process: 18/04174-7 - Analysis of overvoltages in a little more than half-wavelength transmission lines considering the occurrence of corona effect
• Grantee: Thassio Matias Pereira
• Support Opportunities: Scholarships in Brazil - Master