Aspects and Directions of Internal Arc Protection

169 Pages·2016·17.26 MB·English

by  Lauri Kumpulainen

LAURI KUMPULAINEN
Aspects and Directions
of Internal Arc Protection
ACTA WASAENSIA 361
ELECTRICAL ENGINEERING 6
Reviewers Associate Professor Petr Toman
Brno University of Technology
Faculty of Electrical Engineering and Communication
Technická 2848/8
616 00 BRNO
CZECH REP.

Professor Hans Kristian Høidalen
Norwegian University of Science and Technology
Faculty of Information Technology
Department of Electrical Engineering
7491 TRONDHEIM
NORWAY
III
Julkaisija Julkaisupäivämäärä
Vaasan yliopisto Marraskuu 2016
Tekijä Julkaisun tyyppi
Lauri Kumpulainen Artikkeliväitöskirja
Julkaisusarjan nimi, osan numero
Acta Wasaensia, 361
Yhteystiedot ISBN
Vaasan yliopisto 978-952-476-704-0 (painettu)
Teknillinen tiedekunta 978-952-476-705-7 (verkkojulkaisu)
Sähkö- ja energiatekniikan yksikkö ISSN
PL 700 0355-2667 (Acta Wasaensia 361, painettu)
65101 VAASA 2323-9123 (Acta Wasaensia 361, verkkojulkaisu)
1799-6961 (Acta Wasaensia. Sähkötekniikka 6,
painettu)
2343-0532 (Acta Wasaensia. Sähkötekniikka 6,
verkkojulkaisu)
Sivumäärä Kieli
169 englanti
Julkaisun nimike
Valokaarisuojauksen näkökohtia ja kehityssuuntia
Tiivistelmä
Valokaarivika keski- tai pienjännitekojeistossa on yksi sähköverkkojen tuhoisimmista
vikatyypeistä. Sitä voidaan luonnehtia sähköiseksi räjähdykseksi. Se aiheuttaa ihmisille
vakavan palovammariskin ja monia muita vaarallisia vaikutuksia. Valokaari voi aiheuttaa
myös erittäin huomattavia taloudellisia menetyksiä laitevaurioina tai sähkönjakelun ja
tuotantoprosessien keskeytysten seurauksena. Valokaarivikojen vähentämiseksi ja
niiden vaikutusten lieventämiseksi on kehitetty useita menetelmiä. Tässä tutkimuksessa
valokaarisuojauksen menetelmistä on esitetty kattava kokonaiskuva laitteiden suunnit-
telusta valokaaren sammuttamiseen asti. Työssä on myös tutkittu ja esitetty suojauksen
kehityssuuntia.

Osa valokaarivioista kehittyy hitaasti. Tutkimuksessa on tarkasteltu kehittyviin vikoihin
liittyviä ilmiöitä, testattu niiden havaitsemiseen soveltuvia antureita ja luotu suunta-
viivat jatkuvatoimiselle ennakoivalle valokaarisuojaukselle.

Tietoliikenteen merkitys sähköverkoissa kasvaa, kun verkkoja kehitetään älyverkoiksi.
Tämä koskee myös valokaarisuojausta, jossa koko suojausjärjestelmältä edellytetään
erittäin nopeaa toimintaa. Tutkimuksessa on tarkasteltu IEC 61850 -standardin määritte-
lemien GOOSE-viestien hyödyntämistä valokaarisuojausjärjestelmässä ja osoitettu kehi-
tetyn järjestelmän avulla kyseisen tekniikan käyttökelpoisuus ja edut.

Valokaarien aiheuttamien vahinkojen lieventämiseksi tutkimus esittää jo olemassa
olevien ja tehokkaiksi osoittautuneiden menetelmien standardointia, erityisesti
valokaaren optiseen havaitsemiseen perustuvaa suojausta. Valokaaren vaikutusajan
minimoimiseksi voimavaroja kannattaa suunnata katkaisijatekniikan kehittämiseen.
Kriittisimmissä kohteissa oikosulkulaitteet tarjoavat erittäin tehokkaan suojauksen.
Asiasanat
Valokaari, kojeisto, ennakoiva suojaus, sensorit, IEC 61850.

V
Publisher Date of publication
Vaasan yliopisto November 2016
Author Type of publication
Lauri Kumpulainen Doctoral thesis by publication
Name and number of series
Acta Wasaensia, 361
Contact information ISBN
University of Vaasa 978-952-476-704-0 (print)
Faculty of Technology 978-952-476-705-7 (online)
Department of Electrical Engineering ISSN
and Energy Technology 0355-2667 (Acta Wasaensia 361, print)
P.O. Box 700 2323-9123 (Acta Wasaensia 361, online)
FI-65101 Vaasa 1799-6961 (Acta Wasaensia. Electrical
Finland Engineering 6, print)
2343-0532 (Acta Wasaensia. Electrical
Engineering 6, online)
Number of pages Language
169 English
Title of publication
Aspects and Directions of Internal Arc Protection
Abstract
An arc fault in medium voltage or low voltage switchgear is one of the most devastating
fault types in power systems. Term ‘arc flash explosion’ is a good characterization of the
fault type. It causes a serious burn hazard to personnel along with several other safety
hazards. An arc fault may also lead to significant economic losses directly, by damaging
the equipment and indirectly, through power supply outages and production process
interruptions. Several methods have been introduced to prevent arc faults and mitigate
their impacts. In this research a comprehensive overview of the methods has been
given, starting from the design of equipment until the extinction of the fault arc.
Development directions for arc protection have been investigated and suggested.

Part of arc faults develop gradually and it is possible to construct systems for detecting
such faults. In this research, mechanism and phenomena related to developing faults
have been investigated. Moreover, an online monitoring system enabling preemptive
protection has been outlined, and suitable sensors have been tested in a laboratory.

The importance of communication technology in power systems increases along with
the progress of smart grids. This also applies to arc protection systems that require
extremely short operation time. This research has investigated the feasibility of IEC
61850 based GOOSE messaging in arc protection systems, verified the functionality of a
developed implementation and evaluated benefits of the technology.

The dissertation suggests standardization of already existing, effective and proven
protection methods, especially protection based on optical detection. In minimizing the
arc duration, efforts should be directed towards development of circuit breaker
technology. In most critical sites, short-circuit devices can be applied.
Keywords
Arc fault, switchgear, preemptive protection, sensors, IEC 61850.

VII
ACKNOWLEDGEMENT
The results of this doctoral thesis are based on the research activities during the
years 2008-2016. Several people have contributed to the work, and it is a
pleasure to thank all those who have made this thesis possible.
I would like to thank my supervisors professor Kimmo Kauhaniemi and professor
Timo Vekara for guidance and encouragement. I am very grateful to Vamp Oy
and its personnel, especially Juha Rintala, Anssi Jäntti and Olavi Vähämäki for
providing excellent expertise and nice cooperation during all these years. Special
thanks also to former Vamp employees Seppo Pettissalo and Samuel Dahl for
their vast contribution to the development of arc protection technology.
I am very grateful to Dr. G. Amjad Hussain and professor Matti Lehtonen for
excellent cooperation and encouragement during the research on arc prediction
technology at Aalto University. I also express my deep gratitude to IEEE Fellow
John A. Kay, Rockwell Automation, for valuable contribution in our articles.
Special thanks to all other co-authors.
I want to express my gratefulness to current and former colleagues Anssi Mäki,
Katja Sirviö, Jukka Rinta-Luoma and Sampo Voima for encouragement and for
the social network at the University of Vaasa. Professor N. Rajkumar deserves
special thanks for proofreading.

The Graduate School of the University of Vaasa, Ulla Tuominen Foundation and
Vaasan Teknillinen Seura are acknowledged for their financial support, enabling
the finalization of the dissertation.

This dissertation is definitely not my life’s work. This is just a thesis. And work is
only a slice of my life.

September 2016
Lauri Kumpulainen

IX
Contents
ACKNOWLEDGEMENT ............................................................................ VII
1 INTRODUCTION ................................................................................. 1
1.1 Importance of internal arc fault protection ............................... 1
1.2 Objectives of the work ............................................................. 2
1.3 Outline of the thesis ................................................................ 2
1.4 Scientific contribution .............................................................. 3
1.5 Summary of publications ......................................................... 3
1.6 Other publications by the author with closely related topics .... 5
2 INTERNAL ARC FAULTS IN SWITCHGEAR ............................................. 9
2.1 Arc fault phenomenon ............................................................. 9
2.1.1 Definition of internal arc fault ................................... 9
2.1.2 Series and parallel arc faults...................................... 9
2.1.3 Impacts of arc faults ............................................... 10
2.2 Causes of internal arc faults .................................................. 14
3 ARC PROTECTION RELATED STANDARDS ......................................... 15
3.1 Overview of the standardization ............................................ 15
3.2 IEC standards ........................................................................ 16
3.3 IEEE standards ....................................................................... 17
3.4 NFPA 70E ............................................................................... 18
3.5 Discussion on standards ........................................................ 19
4 A COMPREHENSIVE VIEW OF ARC PROTECTION ................................. 20
4.1 Elements of the big picture of arc protection ......................... 20
4.2 Design, education and maintenance ...................................... 21
4.3 Mechanical arc fault protection methods ................................ 22
4.4 Common principles of mitigating the thermal impact ............ 24
4.5 Fault current limitation .......................................................... 24
4.6 Reduction of arc duration ...................................................... 25
4.6.1 Busbar differential protection .................................. 26
4.6.2 Zone-selective interlocking ...................................... 26
4.6.3 Maintenance switch and instantaneous settings ...... 27
4.6.4 Detection of light .................................................... 27
4.6.5 Fast detection of overcurrent .................................. 30
4.6.6 Detection of pressure or sound ............................... 31
4.7 Protection systems based on the detection of light ................ 32
4.7.1 Stand-alone devices ................................................. 32
4.7.2 Arc protection integrated into protection relays ...... 33
4.7.3 Dedicated arc protection systems ............................ 34
4.8 Elimination of the fault arc ..................................................... 35
4.8.1 Importance of the elimination technology ............... 35
4.8.2 Fuses ...................................................................... 36
4.8.3 Circuit breakers ...................................................... 36
4.8.4 Short-circuit devices ................................................ 37
4.9 Summary and areas of development ...................................... 37
X
5 FAST ELIMINATION OF THE FAULT ARC ............................................ 38
5.1 The importance of the speed of the elimination ..................... 38
5.2 Fast conventional circuit breakers .......................................... 38
5.3 Power semiconductor based circuit breakers .......................... 39
5.4 Short-circuit devices .............................................................. 40
5.5 Commercial or patented short-circuit devices ........................ 42
6 PREEMPTIVE ARC FAULT DETECTION ................................................ 43
6.1 Objectives of preemptive fault detection and protection ........ 43
6.2 Mechanisms of slowly developing arc faults ........................... 43
6.3 Phenomena and detection methods indicating a developing
fault ...................................................................................... 45
6.3.1 Classification of the methods .................................. 45
6.3.2 Thermal emissions, infrared radiation and thermal
ionization................................................................ 46
6.3.3 Chemical emissions ................................................ 46
6.3.4 Electromagnetic emissions ...................................... 47
6.3.5 Changes in the electric field .................................... 47
6.3.6 Acoustic emissions ................................................. 48
6.3.7 Optical emissions .................................................... 48
6.3.8 Changes in the frequency spectrum of the current .. 48
6.3.9 Monitoring of zero-sequence voltage ...................... 49
6.3.10 Cable end differential protection algorithm ............ 49
6.4 Comparison of sensor technologies ....................................... 50
6.5 Conclusions ........................................................................... 51
7 EXPERIMENTAL INVESTIGATION OF SENSORS FOR PREEMPTIVE ARC
PROTECTION ................................................................................... 52
7.1 Selection of sensors for online monitoring of switchgear ....... 52
7.2 D-dot sensor .......................................................................... 53
7.3 Rogowski coil ........................................................................ 53
7.4 Loop antenna ........................................................................ 54
7.5 Thermal ionization detector ................................................... 54
7.6 Measurements in the laboratory ............................................. 55
7.6.1 Measurement setups ............................................... 55
7.6.2 Thermal monitoring, ionization sensor .................... 56
7.6.3 Partial discharge measurements .............................. 57
7.6.4 Low power arcing measurements ............................ 59
7.6.5 Analysis of the measured results ............................. 60
7.7 Outline of the connection to upper level systems ................... 61
7.8 Conclusions of the experimental investigations and evaluation
of the practical feasibility ....................................................... 62
8 TOWARDS IEC 61850 GOOSE BASED COMMUNICATION IN ARC
PROTECTION SYSTEMS ..................................................................... 64
8.1 Application of IEC 61850 standard in arc protection systems . 64
8.2 Communication needs in arc protection ................................. 65
8.3 Communication speed requirements ...................................... 66
8.4 Cyber security aspects of GOOSE based communication......... 67
8.5 System architecture of a new, GOOSE based solution ............. 69