Integrated approach for lightning risk assessment of high voltage Air-Insulated switchgear substations

Outdoor high-voltage (HV) air-insulated (AIS) substations provide transmission and distribution of power to the public. Therefore, it is important that the HV AIS substations are equipped with the lightning protection systems to prevent dangerous events and outages due to lightning strikes. Although...

Full description

Saved in:
Bibliographic Details
Main Author: Ong, Chang Shen
Format: Thesis
Published: 2023
Subjects:
Tags: Add Tag
No Tags, Be the first to tag this record!
id my-mmu-ep.12074
record_format uketd_dc
spelling my-mmu-ep.120742024-02-07T06:34:10Z Integrated approach for lightning risk assessment of high voltage Air-Insulated switchgear substations 2023-05 Ong, Chang Shen TH9025-9745 Protection of buildings Including protection from dampness, fire, burglary Outdoor high-voltage (HV) air-insulated (AIS) substations provide transmission and distribution of power to the public. Therefore, it is important that the HV AIS substations are equipped with the lightning protection systems to prevent dangerous events and outages due to lightning strikes. Although power utility companies have applied their preferred lightning protection methods which are mostly outlined in IEEE 998, there is still a high number of incidents of fires and power outages in substations due to lightning strikes each year. Besides that, this lack of a systematic approach also makes it difficult for practitioners to justify the adequacy of their preferred lightning protection methods. Therefore, calculating the lightning risk values in a probabilistic way via the risk assessment process described in IEC 62305-2 can be a viable alternative. For the risk assessment to be carried out according to the standard, a list of assumptions has been made regarding the substations as building structures. Based on IEC 62305-2, the risk values of loss of a human life (R1) and loss of service to the public (R2) for the outdoor HV AIS substations can be calculated and compared to the tolerable risk values (RT). Besides that, the risk assessment will be complemented by a proposed integrated process by including specific inputs regarding the substation characteristics. In this research, five outdoor HV AIS substations with different characteristics such as voltage systems, basic impulse level (BIL), lightning flash density, and striking distances, have been selected for lightning risk assessment. A list of significant risk factors has been identified and compiled, followed by a list of ambiguous risk factors. These significant ambiguous risk factors such as fire load function (rf), environmental factor (CE), LPL class, and other governing factors have been analysed and discussed. Consequently, in addition to having high values for the actual flash density and the lightning collection area of the substations, it is found that the selection of risk factors with a high probability may exceed the tolerable risk in some cases. For the purpose of correlating the results with the ambiguous risk factors, the adjustments in selection to the significant risk factor have been made in successive iterations. These risk factor adjustments can be used to predict the probable consequences by considering the actual adjustment of safety measures in designs. Thus, the lightning risk assessment process for the outdoor HV AIS substations has been successfully integrated by incorporating the substation characteristics, the assumptions made, and the findings of significant ambiguous risk factors. 2023-05 Thesis http://shdl.mmu.edu.my/12074/ http://erep.mmu.edu.my/ masters Multimedia University Faculty of Engineering (FOE) EREP ID: 11754
institution Multimedia University
collection MMU Institutional Repository
topic TH9025-9745 Protection of buildings Including protection from dampness
fire
burglary
spellingShingle TH9025-9745 Protection of buildings Including protection from dampness
fire
burglary
Ong, Chang Shen
Integrated approach for lightning risk assessment of high voltage Air-Insulated switchgear substations
description Outdoor high-voltage (HV) air-insulated (AIS) substations provide transmission and distribution of power to the public. Therefore, it is important that the HV AIS substations are equipped with the lightning protection systems to prevent dangerous events and outages due to lightning strikes. Although power utility companies have applied their preferred lightning protection methods which are mostly outlined in IEEE 998, there is still a high number of incidents of fires and power outages in substations due to lightning strikes each year. Besides that, this lack of a systematic approach also makes it difficult for practitioners to justify the adequacy of their preferred lightning protection methods. Therefore, calculating the lightning risk values in a probabilistic way via the risk assessment process described in IEC 62305-2 can be a viable alternative. For the risk assessment to be carried out according to the standard, a list of assumptions has been made regarding the substations as building structures. Based on IEC 62305-2, the risk values of loss of a human life (R1) and loss of service to the public (R2) for the outdoor HV AIS substations can be calculated and compared to the tolerable risk values (RT). Besides that, the risk assessment will be complemented by a proposed integrated process by including specific inputs regarding the substation characteristics. In this research, five outdoor HV AIS substations with different characteristics such as voltage systems, basic impulse level (BIL), lightning flash density, and striking distances, have been selected for lightning risk assessment. A list of significant risk factors has been identified and compiled, followed by a list of ambiguous risk factors. These significant ambiguous risk factors such as fire load function (rf), environmental factor (CE), LPL class, and other governing factors have been analysed and discussed. Consequently, in addition to having high values for the actual flash density and the lightning collection area of the substations, it is found that the selection of risk factors with a high probability may exceed the tolerable risk in some cases. For the purpose of correlating the results with the ambiguous risk factors, the adjustments in selection to the significant risk factor have been made in successive iterations. These risk factor adjustments can be used to predict the probable consequences by considering the actual adjustment of safety measures in designs. Thus, the lightning risk assessment process for the outdoor HV AIS substations has been successfully integrated by incorporating the substation characteristics, the assumptions made, and the findings of significant ambiguous risk factors.
format Thesis
qualification_level Master's degree
author Ong, Chang Shen
author_facet Ong, Chang Shen
author_sort Ong, Chang Shen
title Integrated approach for lightning risk assessment of high voltage Air-Insulated switchgear substations
title_short Integrated approach for lightning risk assessment of high voltage Air-Insulated switchgear substations
title_full Integrated approach for lightning risk assessment of high voltage Air-Insulated switchgear substations
title_fullStr Integrated approach for lightning risk assessment of high voltage Air-Insulated switchgear substations
title_full_unstemmed Integrated approach for lightning risk assessment of high voltage Air-Insulated switchgear substations
title_sort integrated approach for lightning risk assessment of high voltage air-insulated switchgear substations
granting_institution Multimedia University
granting_department Faculty of Engineering (FOE)
publishDate 2023
_version_ 1794019134054334464