Circuit - based transient model of grounding electrode with consideration of soil ionization and current rate of rise factors

The behaviour of a grounding electrode can be predicted by using either the electrical circuit model or electromagnetic computation. Despite its advantages over the latter, the grounding circuit model fails to accurately predict the behaviour under transient conditions due to the absence of two key...

Full description

Saved in:

Bibliographic Details
Main Author:	Mokhtari, Mehrdad
Format:	Thesis
Language:	English
Published:	2016
Subjects:	TK Electrical engineering Electronics Nuclear engineering
Online Access:	http://eprints.utm.my/id/eprint/78197/1/MehrdadMokhtariPFKE2016.pdf
Tags:	Add Tag No Tags, Be the first to tag this record!

id	my-utm-ep.78197
record_format	uketd_dc
spelling	my-utm-ep.781972018-07-28T06:26:23Z Circuit - based transient model of grounding electrode with consideration of soil ionization and current rate of rise factors 2016-04 Mokhtari, Mehrdad TK Electrical engineering. Electronics Nuclear engineering The behaviour of a grounding electrode can be predicted by using either the electrical circuit model or electromagnetic computation. Despite its advantages over the latter, the grounding circuit model fails to accurately predict the behaviour under transient conditions due to the absence of two key factors, namely the soil ionization, and the current rate–of–rise. A new equivalent circuit model of a grounding electrode with dynamic circuit elements (Rd, Cd, and Ld) was developed to consider both soil ionization and current rate–of–rise factors. A generalized formula was derived to calculate the dynamic inductance, Ld, for all standard current wave shapes such as Conseil International des Grands Réseaux Électriques (CIGRE), double–exponential, and IEC 62305–1 (International Electrotechnical Commission). The computed inductance, Ld, dynamically changes with the change in the lightning current parameters, thus improving its accuracy for all current rate–of–rise conditions. The consideration for the soil ionization effect on grounding electrode resistance, Rd, and soil capacitance, Cd, within the equivalent circuit model was achieved by modelling the soil with a network of two layer capacitors (TLC) in which soil particles and air voids are the TLC components. Differential equations were derived to incorporate the soil ionization phenomenon inside the TLC network. The voltage response of the new equivalent circuit model and the dynamic circuit elements were determined by using the above–suggested methods, is more accurate than that of the conventionally determined grounding circuit models. The overall differences between the equivalent circuit model and several experiments are 3.3% for the electrode resistance and 2.8% for the electrode peak voltage. The new equivalent circuit model helps to optimize the overall grounding electrode design, and to provide a better fast transient protection and insulation coordination. 2016-04 Thesis http://eprints.utm.my/id/eprint/78197/ http://eprints.utm.my/id/eprint/78197/1/MehrdadMokhtariPFKE2016.pdf application/pdf en public http://dms.library.utm.my:8080/vital/access/manager/Repository/vital:97133 phd doctoral Universiti Teknologi Malaysia, Faculty of Electrical Engineering Faculty of Electrical Engineering
institution	Universiti Teknologi Malaysia
collection	UTM Institutional Repository
language	English
topic	TK Electrical engineering Electronics Nuclear engineering
spellingShingle	TK Electrical engineering Electronics Nuclear engineering Mokhtari, Mehrdad Circuit - based transient model of grounding electrode with consideration of soil ionization and current rate of rise factors
description	The behaviour of a grounding electrode can be predicted by using either the electrical circuit model or electromagnetic computation. Despite its advantages over the latter, the grounding circuit model fails to accurately predict the behaviour under transient conditions due to the absence of two key factors, namely the soil ionization, and the current rate–of–rise. A new equivalent circuit model of a grounding electrode with dynamic circuit elements (Rd, Cd, and Ld) was developed to consider both soil ionization and current rate–of–rise factors. A generalized formula was derived to calculate the dynamic inductance, Ld, for all standard current wave shapes such as Conseil International des Grands Réseaux Électriques (CIGRE), double–exponential, and IEC 62305–1 (International Electrotechnical Commission). The computed inductance, Ld, dynamically changes with the change in the lightning current parameters, thus improving its accuracy for all current rate–of–rise conditions. The consideration for the soil ionization effect on grounding electrode resistance, Rd, and soil capacitance, Cd, within the equivalent circuit model was achieved by modelling the soil with a network of two layer capacitors (TLC) in which soil particles and air voids are the TLC components. Differential equations were derived to incorporate the soil ionization phenomenon inside the TLC network. The voltage response of the new equivalent circuit model and the dynamic circuit elements were determined by using the above–suggested methods, is more accurate than that of the conventionally determined grounding circuit models. The overall differences between the equivalent circuit model and several experiments are 3.3% for the electrode resistance and 2.8% for the electrode peak voltage. The new equivalent circuit model helps to optimize the overall grounding electrode design, and to provide a better fast transient protection and insulation coordination.
format	Thesis
qualification_name	Doctor of Philosophy (PhD.)
qualification_level	Doctorate
author	Mokhtari, Mehrdad
author_facet	Mokhtari, Mehrdad
author_sort	Mokhtari, Mehrdad
title	Circuit - based transient model of grounding electrode with consideration of soil ionization and current rate of rise factors
title_short	Circuit - based transient model of grounding electrode with consideration of soil ionization and current rate of rise factors
title_full	Circuit - based transient model of grounding electrode with consideration of soil ionization and current rate of rise factors
title_fullStr	Circuit - based transient model of grounding electrode with consideration of soil ionization and current rate of rise factors
title_full_unstemmed	Circuit - based transient model of grounding electrode with consideration of soil ionization and current rate of rise factors
title_sort	circuit - based transient model of grounding electrode with consideration of soil ionization and current rate of rise factors
granting_institution	Universiti Teknologi Malaysia, Faculty of Electrical Engineering
granting_department	Faculty of Electrical Engineering
publishDate	2016
url	http://eprints.utm.my/id/eprint/78197/1/MehrdadMokhtariPFKE2016.pdf
_version_	1747817930791321600

Circuit - based transient model of grounding electrode with consideration of soil ionization and current rate of rise factors

Similar Items