C62.22a-2013 - IEEE Guide for the Application of Metal-Oxide Surge Arresters for Alternating-Current...

IEEE Guide for the Application of Metal-Oxide Surge Arresters for Alternating-Current Systems Amendment 1: Supplement to Consider Energy Handling Capabilities

Sponsored by the Surge Protective Devices Committee

IEEE 3 Park Avenue New York, NY 10016-5997 USA

IEEE Power and Energy Society

IEEE Std C62.22a™-2013 (Amendment to

IEEE Std C62.22TM-2009)

Authorized licensed use limited to: UNIVERSIDADE FEDERAL DE SAO JOAO DEL REI. Downloaded on January 23,2014 at 00:45:00 UTC from IEEE Xplore. Restrictions apply.


IEEE Std C62.22aTM-2013 (Amendment to

IEEE Std C62.22TM-2009)

IEEE Guide for the Application of Metal-Oxide Surge Arresters for Alternating-Current Systems Amendment 1: Supplement to Consider Energy Handling Capabilities

Sponsor

Surge Protective Devices Committee of the IEEE Power and Energy Society

Approved 14 June 2013

IEEE-SA Standards Board


Copyright © 2013 IEEE. All rights reserved.

Abstract: New tests added to IEEE Std C62.11TM-2012: a switching surge energy capability test (thermal energy rating), a repetitive single-impulse withstand capability test, and the inductive voltage drop effects of the internal arrester metal current carrying components determined during the front-of-wave (FOW) discharge voltage test are included in this amendment to IEEE Std C62.22TM-2009. Keywords: distribution lines, insulation coordination, IEEE C62.11TM, IEEE C62.22TM, IEEE C62.22aTM, lightning, metal-oxide surge arrester, overvoltage, substations, surge arrester, switching surges, transmission lines

•

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iv Copyright © 2013 IEEE. All rights reserved.

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v Copyright © 2013 IEEE. All rights reserved.

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vi Copyright © 2013 IEEE. All rights reserved.

Participants

At the time this draft guide was submitted to the IEEE-SA Standards Board for approval, the Continuous Revision of C62.22 Working Group had the following membership:

Thomas J. Rozek, Chair Thomas Field, Vice Chair

Dilip Biswas Michael Champagne Mike Comber David D’Hooge John DuPont Cliff Erven Christine Goldsworthy Steven Hensley Ray Hill Volker Hinrichsen Bengt Johnnerfelt

Joseph L. Koepfinger Chris Kulig Senthil Kumar Dennis Lenk Jody Levine Paul Lindemulder Mark McVey Iuda Morar Marco Morello Michael Ramarge

Jeff Steiner James Strong Keith Stump Eva Tarasiewicz Edgar Taylor Rao Thallam Arnold Vitols Larry Vogt Reigh Walling James Wilson Jonathan Woodworth

The following members of the individual balloting committee voted on this guide. Balloters may have voted for approval, disapproval, or abstention. Roy Alexander Steven Alexanderson Saleman Alibhay Robert Arno Robert Barnett G. Bartok George Becker W. J. Bil Bergman Wallace Binder Kenneth Bow Carl Bush William Byrd Thomas Callsen Paul Cardinal Michael Champagne Suresh Channarasappa Bill Chiu Keith Chow Robert Christman Michael Comber Stephen Conrad Brian Cramer David Crotty Chuanyou Dai Glenn Davis Matthew Davis Carlo Donati Gary Donner Randall Dotson Fred Elliott Cliff Erven Dan Evans Jorge Fernandez Daher Rostyslaw Fostiak Fredric Friend

Michael Garrels Waymon Goch Jalal Gohari James Graham Thomas Grebe Randall Groves John Harder John Harley Richard Harp David Harris Jeffrey Hartenberger Jeffrey Helzer Steven Hensley Lee Herron Gary Heuston Ray Hill Werner Hoelzl Ronald Hotchkiss Mayank Jain Joseph Jancauskas Edward Jankowich Dennis Johnson Andrew Jones Laszlo Kadar Gael Kennedy Jeffrey Kester Yuri Khersonsky James Kinney Joseph L. Koepfinger Boris Kogan Albert Kong Jim Kulchisky Saumen Kundu Chung-Yiu Lam Benjamin Lanz

Thomas La Rose Michael Lauxman Paul Lindemulder Greg Luri Ahmad Mahinfallah J. Dennis Marlow Albert Martin Michael Maytum William McBride James Michalec Daleep Mohla Georges Montillet Arun Narang Jeffrey Nelson Michael S. Newman Raymond Nicholas Joe Nims Hans-Wolf Oertel Lorraine Padden Mirko Palazzo Bansi Patel Shawn Patterson Percy Pool Alvaro Portillo Michael Ramarge Samala Santosh Reddy Michael Roberts Charles Rogers John Rossetti Marnie Roussell Thomas Rozek Steven Sano Bartien Sayogo Carl Schuetz Devki Sharma


vii Copyright © 2013 IEEE. All rights reserved.

Hyeong Sim James Smith Jerry Smith John Spare Gary Stoedter Keith Stump William Taylor David Tepen Rao Thallam

James Timperley Peter Tirinzoni John Toth Nijam Uddin Michael Valenza John Vergis Jane Verner Matthew Wakeham

Reigh Walling William Walter Daniel Ward Donald Wengerter Kenneth White James Wilson John Wilson Jonathan Woodworth Janusz Zawadzki

When the IEEE-SA Standards Board approved this guide on 14 June 2013, it had the following membership:

John Kulick, Chair David J. Law, Vice Chair

Richard H. Hulett, Past Chair Konstantinos Karachalios, Secretary

Masayuki Ariyoshi Peter Balma Farooq Bari Ted Burse Wael William Diab Stephen Dukes Jean-Philippe Faure Alexander Gelman

Mark Halpin Gary Hoffman Paul Houzé Jim Hughes Michael Janezic Joseph L. Koepfinger* Oleg Logvinov

Ron Petersen Gary Robinson Jon Walter Rosdahl Adrian Stephens Peter Sutherland Yatin Trivedi Phil Winston Yu Yuan

*Member Emeritus

Also included are the following nonvoting IEEE-SA Standards Board liaisons:

Richard DeBlasio, DOE Representative Michael Janezic, NIST Representative

Patrick Gibbons

IEEE Standards Program Manager, Document Development

Malia Zaman IEEE Standards Program Manager, Technical Program Development


viii Copyright © 2013 IEEE. All rights reserved.

Introduction

This introduction is not part of IEEE Std C62.22aTM-2013, IEEE Guide for the Application of Metal-Oxide Surge Arresters for Alternating-Current Systems—Amendment 1: Supplement to Consider Energy Handling Capabilities.

IEEE Std C62.11, IEEE Standard for Metal-Oxide Surge Arresters for AC Power Circuits (>1 kV), has been revised with several changes that affect surge arrester application. These changes include the addition of a switching surge energy capability test (thermal energy rating), a repetitive single-impulse withstand capability test, and the inductive voltage drop effects of the arrester lead lengths determined during the front-of-wave (FOW) discharge voltage test. The application guide for station and intermediate class metal-oxide surge arresters is being amended to incorporate changes necessary to provide proper arrester selection guidance.

This amendment to IEEE Std C62.22-2009 contains the following changes:

⎯ The discussion on energy handling capability is amended in 4.2.5. Additional information on the switching surge energy rating and single impulse withstand rating is provided in the amended 4.2.5a and 4.2.5b.

⎯ The first two paragraphs of 5.2.1.3 are amended to provide guidance in arrester selection based on the switching surge energy capability test. Supporting data is included with the addition of Table 1.

⎯ Guidance to account for the inductive voltage drop of the internal arrester metal current carrying components during the FOW discharge voltage test is included in the amended 5.2.2.1.


ix Copyright © 2013 IEEE. All rights reserved.

Contents

2. Normative references .................................................................................................................................. 2

4. General considerations ............................................................................................................................... 2

5. Protection of transmission equipment and substations ............................................................................... 3



1


IEEE Guide for the Application of Metal-Oxide Surge Arresters for Alternating-Current Systems

Amendment 1: Supplement to Consider Energy Handling Capabilities

IMPORTANT NOTICE: This standard is not intended to ensure safety, security, health, or environmental protection. Implementers of the standard are responsible for determining appropriate safety, security, environmental, and health practices or regulatory requirements.

This IEEE document is made available for use subject to important notices and legal disclaimers. These notices and disclaimers appear in all publications containing this document and may be found under the heading “Important Notice” or “Important Notices and Disclaimers Concerning IEEE Documents.” They can also be obtained on request from IEEE or viewed at http://standards.ieee.org/IPR/disclaimers.html.

NOTE—The editing instructions contained in this amendment define how to merge the material contained therein into the existing base standard and its amendments to form the comprehensive standard.

The editing instructions are shown in bold italic. Four editing instructions are used: change, delete, insert, and replace. Change is used to make corrections in existing text or tables. The editing instruction specifies the location of the change and describes what is being changed by using strikethrough (to remove old material) and underscore (to add new material). Delete removes existing material. Insert adds new material without disturbing the existing material. Insertions may require renumbering. If so, renumbering instructions are given in the editing instruction. Replace is used to make changes in figures or equations by removing the existing figure or equation and replacing it with a new one. Editing instructions, change markings, and this NOTE will not be carried over into future editions because the changes will be incorporated into the base standard.


IEEE Std C62.22a-2013 IEEE Guide for the Application of Metal-Oxide Surge Arresters for Alternating-Current Systems


2 Copyright © 2013 IEEE. All rights reserved.

2. Normative references

Add the following to Clause 2:

IEEE Std C62.11TM-2012, IEEE Standard for Metal-Oxide Surge Arresters for AC Power Circuits (> 1 kV).

4. General considerations

Delete the three paragraphs of the existing 4.2.5 preceding 4.2.5.1. Insert the new 4.2.5, 4.2.5a, and 4.2.5b before 4.2.5.1:

4.2.5 Energy handling capability

When a metal-oxide surge arrester (MOSA) is subjected to a surge from the system to which it is installed, it responds by shunting surge current thereby limiting the overvoltage on the protected equipment. The action of the arrester results in the transfer of charge and in the absorption of energy from the system, which is rapidly converted to heat. The charge transfer is quantified as coulombs and the energy absorption is quantified as joules. Both types of arrester durability (energy absorption and charge transfer) are tested for each arrester design to allow arrester users to compare the capability of the arrester with the requirements of the system. The energy absorption capability is characterized by the switching surge energy rating test. The charge transfer capability is characterized by the single impulse withstand rating test.

When metal-oxide arresters are energized at steady state, valve elements will conduct leakage current at low levels, which is converted into heat at a low rate. Under these normal operating conditions (i.e., absence of overvoltage), there is a balance between the heat generated by the valve elements and the heat dissipated by the arrester through conduction, convection, and radiation, such that a stable operating condition is maintained. Overvoltage and surge events disturb this stable condition by causing the valve elements to absorb increased levels of energy for some limited amount of time. The subsequent response and temperature rise of the arrester depends greatly on the magnitude and rate of energy input and on the specific design of the arrester.

For simple applications where overvoltages are well defined, the resulting energy absorbed by the arrester can be determined by calculation (use arrester minimum voltage characteristics for energy calculation). For complex situations, computer simulation studies using electromagnetic transient simulation software may be required. These studies require knowledge of the arrester minimum and maximum voltage-current characteristics, which are usually available from the arrester manufacturer. With these types of studies, the switching surge energy rating (energy absorption) and single impulse withstand rating (charge transfer) as stated by the manufacturer can be compared to the requirements of the system.

4.2.5a Switching surge energy rating

This station and intermediate class arrester characteristic is related to the energy absorption capability of the arrester. Typical switching surges can last for a few milliseconds to many milliseconds and in some cases can arrive at the arrester one or more cycles apart. This rating quantifies the maximum energy an arrester is capable of absorbing and remain thermally stable after the event with ac voltage applied.





4.2.5b Single impulse withstand rating

This station and intermediate class arrester characteristic is related to the charge transfer capability of the arrester. If an arrester is applied in an application where the voltage after a surge event is removed, this characteristic quantifies the surge durability more appropriately than the thermally influenced switching surge energy rating. This rating quantifies the electromechanical capability of the arrester that is stressed during a surge event. The unit of measure for this rating is coulomb because the charge transfer is not dependent on the discharge voltage of the arrester as is the energy rating in joules. There are no recommended levels for this characteristic because these applications tend to be special in nature. The test is standardized; therefore, the rating can be used to compare one arrester to another.

5. Protection of transmission equipment and substations

Change the first two paragraphs of 5.2.1.3 as follows:

5.2.1.3 Switching surge durability

Surge arresters dissipate switching surges by absorbing thermal energy. A surge arrester controls the level of the switching surge voltage across equipment by diverting the switching surge current. During the process, the surge arrester heats up and then dissipates thermal energy into the surrounding medium. The amount of energy is related to the prospective switching surge magnitude, its wave shape, the system impedance, circuit topology, the arrester voltage-current characteristics, and the number of operations (single/multiple events). The selected arrester should have an energy capability a switching surge energy rating greater than the energy associated with the expected switching surges on the system. If the application calls for the immediate de-energization of the arrester and the relay protection scheme does not include reclosing, the single impulse withstand rating can be used to select the durability of the arrester. In this case, the charge transfer rating of the arrester in coulombs should be greater than that associated with the system requirements.

The actual amount of energy discharged by a metal-oxide arrester during a switching surge can be determined through detailed system studies performed with an electromagnetic transient simulation. a transient network analyzer (TNA) and/or a digital circuit analysis program such as the EMTP. When such study results are not available, the approximate arrester duty due to energizing and reclosing operations on transmission lines can be estimated from Equation (5) and curves. The arrester class should be selected on the basis of required level of protection (protective levels are summarized in Table 1.A). The right-most column of Table 1.A lists the minimum two shot switching surge energy requirements by letter class (letter classes range from A through N) and the corresponding kJ/kV MCOV. The designations for energy classes are determined through testing prescribed in 8.14 of IEEE Std C62.11TM-2012 (see Table 13 of that standard).

Insert Table 1.A prior to Figure 7 in 5.2.1.3:


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Change the following in subclause 5.2.2.1 as shown:

5.2.2.1 Determination of protective levels

Protective levels are determined by either sparkover voltages or discharge voltages of the arrester under consideration, based on the measurement procedure in subclauses 8.2 and 8.4 of IEEE Std C62.11-2012. The following protective levels should be considered:

a) FOW: The higher value of FOW sparkover or arrester discharge voltage cresting in 0.5 µs at the classifying current the normalized FOW discharge voltage. Note that there are two values offered by manufacturers for the FOW discharge voltage. The values without inductive voltage drop can be used in arrester modeling. The values with the inductive voltage drop (which accounts for the internal arrester metal current carrying components such as spacers, springs, end fittings, etc.) should be the value compared to the FOW sparkover.

b) LPL: The higher value of lightning impulse sparkover for a 1.2/50 lightning impulse or normalized arrester discharge voltage that results from an 8/20 current wave. The appropriate current magnitude is determined by the system voltage per Table 2.

c) SPL: The higher value of switching impulse sparkover or normalized arrester discharge voltage that results from a current wave with a time to actual crest of 45 µs to 60 µs. The appropriate current magnitude is based on the system voltage as contained in 5.2.2.3.


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