Transient Overvoltage Analysis in the Medium Voltage Substations Based on Full-Wave Modeling of Two-layer grounding System

Research output: Contribution to journalJournal articleResearchpeer-review

4 Citations (Scopus)
80 Downloads (Pure)

Abstract

In this paper, a comprehensive investigation of substation grounding soil structure effects on switching/lightning transients is presented. The full-wave computational solution Method of Moments (MoM) is adopted to solve Maxwell's equations. The significant advantage of this technique is its ability to deal effectively with substation grounding systems (SGSs) at high frequency. This evaluation is carried out considering two soil structures: (1) a uniform soil and (2) soil with a layered structure. The impacts of both soil structures on the peak transient overvoltage values are compared. To begin with, the harmonic impedance matrix (HIM) of the layered multi-terminal SGS is computed. Then, a vector fitting approach is employed to incorporate the accurate SGS behavior by relying on the obtained HIM into time domain simulations. Finally, the transient overvoltages and maximum ground potential rise (GPR) are computed. The chief contribution of this paper is the transient assessment of the two-layer multi-terminal soil structure of the large SGS taking into account the frequency dependence model of the electrical parameters of soil, which is not generally investigated and instead, treated simplistically. According to the results of the study, the lack of an exact grounding system models may lead to underestimations/overestimations of the GPR and the overvoltage values. The results demonstrate the need for the grounding modeling of SGS considering layered soil structure to be incorporated into power system transient analysis in a wide range of frequencies.

Original languageEnglish
Article number108139
JournalElectric Power Systems Research
Volume211
Pages (from-to)1
Number of pages13
ISSN0378-7796
DOIs
Publication statusPublished - Oct 2022

Keywords

  • GPR
  • Harmonic impedance
  • Substation grounding system
  • Transient overvoltage
  • Two-layer soil structure
  • Vector fitting method

Fingerprint

Dive into the research topics of 'Transient Overvoltage Analysis in the Medium Voltage Substations Based on Full-Wave Modeling of Two-layer grounding System'. Together they form a unique fingerprint.

Cite this