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Grounding – Industry Experiences Alberta Power Industry Consortium & University of Alberta Professional Development Course Power System Grounding – Industry Experiences Organized By Alberta Power Industry Consortium & University of Alberta AESO AltaLink ATCO Enmax Epcor FortisAlberta Instructed By Joseph Kuffar & Dennis Peters, Enmax Nerkez Lalic, Epcor Dennis Rasmusson, AltaLink Wilsun Xu, University of Alberta May 28 & 30, 2013 Calgary & Edmonton, Alberta, Canada Abstract Power system grounding is probably one of the most confusing subjects in the field of power engineering. It covers a wide range of topics, such as short‐circuit responses of power networks, electric field distributions of grounding structures, and implications to safe work practice. This course is a continuation of the 2012 APIC course on power system grounding. Building on the fundamental theories taught last year, the current course will share actual industry practices, experiences, investigations of the APIC companies. Relevant technical concepts and theories behind the practices will also be explained to facilitate learning. This course will mainly focus on grounding related electrical safety issues. A few cases involving the grounding performance of power systems will also be discussed. 1 1 Confidentiality Requirement This course material was prepared by the University of Alberta for the ultimate benefit of the Alberta Power Industry Consortium members (hereinafter called “SPONSORS”). It may contain confidential research findings, trade secrets, proprietary materials (collectively called “Proprietary Information”). The term Proprietary Information includes, but is not limited to, plans, drawings, designs, specifications, new teaching materials, trade secrets, processes, systems, manufacturing techniques, model and mock-ups, and financial or cost data. The document is made available to the sponsors only. The Sponsors will use all reasonable efforts to treat and keep confidential, and cause its officers, members, directors, employees, agents, contractors and students, if any, (“Representatives”) to treat and keep confidential, and Proprietary Information in the document and the document itself. This course material shall not be disclosed to any third party without the consent of the Alberta Power Industry Consortium. Disclaimer This document may contain reports, guidelines, practices that are developed by the University of Alberta and the members of the Alberta Power Industry Consortium (APIC). Neither the APIC members, the University of Alberta, nor any of other person acting on his/her behalf makes any warranty or implied, or assumes any legal responsibility for the accuracy of any information or for the completeness or usefulness of any apparatus, product or process disclosed, or accept liability for the use, or damages resulting from the use, thereof. Neither do they represent that their use would not infringe upon privately owned rights. Furthermore, the APIC companies and the University of Alberta hereby disclaim any and all warranties, expressed or implied, including the warranties of merchantability and fitness for a particular purpose, whether arising by law, custom, or conduct, with respect to any of the information contained in this document. In no event shall the APIC companies and the University of Alberta be liable for incidental or consequential damages because of use or any information contained in this document. Any reference in this document to any specific commercial product, process or service by trade name, trademark, manufacture, or otherwise does not necessarily constitute or imply its endorsement or recommendation by the University of Alberta and/or the APIC companies. 2 2 About the Alberta Power Industry Consortium: The Alberta Power Industry Consortium consists of six Alberta utility companies (AESO, AltaLink, ATCO, Enmax, Epcor and FortisAlberta) and the University of Alberta. Established in the fall of 2007, its goal is to bring Alberta power companies together, with the University of Alberta as the coordinating organization, to solve technical problems of common interest, to produce more power engineering graduates, to support the professional development of current employees, and to promote technical cooperation and exchange in Alberta’s power utility community. 3 3 About the instructors: Mr. Joseph Kuffar is a 2004 graduate of Electrical Engineering from the University of Saskatchewan. Joseph has 9 years technical engineering experience. His work experience includes system planning, distribution system design, material standards and QC, and asset management (distribution & network). He is currently holds a position with ENMAX as Supervising Engineer, T&D Asset Management. Joseph is a registered professional engineer in the province of Alberta. Mr. Nerkez Lalic is a 1972 graduate of Electric Power Engineering Faculty from the University of Sarajevo, Bosnia & Herzegovina. He worked for international equipment manufacturing, engineering and consulting companies on the design, construction, testing, commissioning and EPC management of high voltage substation and overhead/underground transmission line projects. He has been with EPCOR for nine years and currently holds the position of Senior Manager, Transmission Projects. Mr. Lalic has a special interest in improving EPC processes of complex engineering projects, focusing on implementation of COAA standardized engineering contracts in practice and safety standards improvement, coordination and implementation during execution of complex construction works. Mr. Lalic is a registered professional engineer in the province of Alberta. Mr. Dennis Peters is a 2008 graduate of Electrical Engineering from the University of Saskatchewan. Dennis worked for ENMAX upon graduation and has 5 years of engineering experience. His work experience includes network secondary distribution customer and system design and recently network and distribution asset management. He has special interest in network secondary distribution material specifications and material QC and QA. Dennis currently holds a position with ENMAX as T&D Asset Management Engineer. Dennis is a registered professional engineer in the province of Alberta. Mr. Dennis Rasmusson is a 1972 graduate of Electrical Engineering Technology from NAIT in Edmonton. Upon graduation Dennis spent the first 10 year of his career in the field in the area of protection and control. He spent the next 17 years in various positions in management in both transmission and distribution. During this time his roles included Manager of Substation Construction and Operations, Regional Transmission Maintenance Manager, Area Manager of Sherwood Park, and Director of Asset Management. During the last 15 years his main focus was on safety and held roles of Safety Manager and Director of EH&S. He has been working in the electrical utility industry for 42 years. In 2010 Dennis started his retirement by working as a safety specialist on a reduced work week and plans on retiring late 2013. Dr. Wilsun Xu obtained a B.Sc. degree from China in 1982 and PhD from UBC in 1989. He worked in BC Hydro from 1989 to 1996. He joined the University of Alberta as a faculty member in 1996 and is currently a research chair professor at the U of A. Dr. Xu has extensive engineering and research experiences in the area of power quality. His research work on multiphase power system analysis has helped him to formulate a methodology to analyze faulted power systems with complex grounding configurations. In recent years, Dr. Xu has used the methodology to investigate several issues related to power system grounding. Dr. Xu is a registered professional engineer in the province of Alberta. 4 4 Course Outline 1. Review: Basic concepts of power system grounding Performance grounding versus safety grounding Basics of safety grounding Basics of performance grounding 2. Grounding and safe work practice Theory: Equipotential bonding and grounding transmission lines Case: Working on isolated transmission facilities – Altalink practice Case: Deep grounding‐well method for improving Epcor substation grounding Theory: Characteristics of GPR as affected by grounding arrangements 3. Grounding performance of power systems Theory: measurement of grounding resistances Case: Distribution grounding system assessment and replacement program of Enmax Case: Bonding feeder and substation neutrals – pros, cons, and ATCO practice Case: Does improving grounding help to reduce telephone interference? 5 5 Alberta Power Industry Consortium & University of Alberta Professional Development Course Power System Grounding - Industry Experiences by Wilsun Xu, Professor [email protected] Department of Electrical & Computer Engineering University of Alberta May 2013 6 Background of this course • The 2012 APIC course covered various concepts & theories of power system grounding; • The course feedback indicates that there is an interest to learn actual cases and industry experiences on grounding; • This course is developed as a continuation of the last year’s course, with a focus on industry applications and experiences; • Key theories will also be reviewed to enhance learning; • Industry speakers are invited to share their experiences 7 Background of this course Industry instructors & cases Joseph Kuffar, Supervising Engineer, T&D Asset Management, Enmax Dennis Peters, Engineer, T&D Asset Management, Enmax • Case: Distribution grounding system assessment and replacement program of Enmax Nerkez Lalic, Senior Manager - Transmission Projects,
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