Improve Safety with High-Impedance Fault Detection

Authors:  Daqing Hou, Héctor J. Altuve, and Armando Guzmán

Company: Schweitzer Engineering Laboratories, Inc.

Abstract

In overhead distribution lines, fallen power conductors on poorly conductive surfaces, tree branches contacting power lines, and dirty insulators are typical causes of high-impedance faults (HIFs). The fault current is very low and may equal zero when the conductor falls on asphalt or dry sand. Because of low-fault currents, HIFs neither interrupt service to customers nor cause thermal damage to power system equipment. However, HIFs resulting from downed conductors are potentially hazardous to humans and livestock and are a concern for public safety. Traditional feeder protection devices typically fail to detect downed power conductors. New technologies are available for downed conductor detection, but are being adopted very slowly. This conference discusses downed conductor problems and describes methods for solving them. In particular, we present an HIF detection algorithm that uses traditional relay logic and is available in a family of distribution system protection relays.  The algorithm is easier to understand and simpler to implement than many black-box detection methods such as neural networks. We also present several high-impedance fault field tests to show the algorithm performance. The conference raises awareness, shows different aspects of the problem, and provides ideas to accelerate adoption of this technology.

Presenter:  Héctor J. Altuve

Biography

Héctor J. Altuve Ferrer received his BSEE degree in 1969 from the Central University of Las Villas in Santa Clara, Cuba, and his Ph.D. in 1981 from Kiev Polytechnic Institute in Kiev, Ukraine. From 1969 until 1993, Dr. Altuve served on the faculty of the Electrical Engineering School at the Central University of Las Villas. From 1993 to 2000, he served as professor of the Graduate Doctoral Program in the Mechanical and Electrical Engineering School at the Autonomous University of Nuevo León in Monterrey, Mexico. In 1999 through 2000, he was the Schweitzer Visiting Professor in the Department of Electrical Engineering at Washington State University. Dr. Altuve joined Schweitzer Engineering Laboratories, Inc. in January 2001, where he is currently a distinguished engineer and director of technology for Latin America. He has authored and coauthored more than 100 technical papers and several books and holds four patents. His main research interests are in power system protection, control, and monitoring. Dr. Altuve is an IEEE senior member.

Safety Instrumented Systems for Process Sector Industry

Author: Francisco Espinosa

Company:  Schneider Electric, Services & Projects Business, Mexico

Abstract

Design concepts used in the application of Safety Instrumented Systems for Process Sector Industry. Standards history safety-related. The importance of IEC61508 and IEC61511 standards. Prescriptive standards vs performance-base standards, overall safety systems performance, safety and reliability, diagnostic coverage, hardware fault tolerance, probability failure on demand, fault tolerant architectures, failure modes and failures rates, test interval and repair time, safety integrity levels and the safety life-cycle, safety management process and safety assessment.

Presenter:  Francisco Espinosa

Biography

Francisco Espinosa is in charge for Application Process Engineer Department in Schneider Electric Mexico since 1993. From 2008 is specialized in Safety Systems. He obtained his B.S. degree in UNAM ENEP Aragón, and he is certified as TÜV Functional Safety Engineer by TÜV Rheinland. Member of the ISA. Moderator in Funtional Safety forum and blogger about Functional Safety on Campus web site on Schneider Electric.

First of Its Kind, New, Right, Safe and Reliable

Author:  Marco Aurelio Flores-Verdugo

Company: TECMEN S.A. de C.V.

Abstract

Significant technological breakthrough need not be unreliable nor unsafe. A comprehensive research and development program, followed by  intensive full-scale testing of main components and  inventor involvement in pre-commissioning audits can make the difference.  This proprietary steel-making process (now owned by Techint), has operated with 100% reliability since the day it was started in 1998, producing several millions tons of DRI per year.  In this conference we will look at the major milestones in its development.

Presenter:  Marco A. Flores-Verdugo

Biography

Marco A. Flores-Verdugo is a graduate from The National University of Mexico (UNAM) with graduate studies at the innovation center of MIT as well as the Aeronautics and Astronautics Department.
A well known worldwide inventor and teacher, in topics that go from banana peelers to specialized high-temperature pneumatic conveying, valves, expansion joints, pipelines and high and low temperature wear-resisting alloys.  He teaches accident and failure analysis and prevention to the main power, steel, mining and oil companies worldwide; author of "The Macho Syndrome" and "Designed for Disaster". Has been awarded the ADIAT prize for Industrial Innovation and has received multiple recognitions from several universities for his support in the development of the engineering curricula.