EN IEC 60255-181:2019

Measuring relays and protection equipment - Part 181: Functional requirements for frequency protection

IEC 60255-181:2019 specifies the minimum requirements for functional and performance evaluation of frequency protection. This document also defines how to document and publish performance test results. This document covers the functions based on frequency measurement or rate of change of frequency measurements. This document also covers frequency protection where additional blocking elements are used. This document defines the influencing factors that affect the accuracy under steady state conditions and performance characteristics during dynamic conditions. The test methodologies for verifying performance characteristics and accuracy are also included in this document.

Messrelais und Schutzeinrichtungen - Teil 181: Funktionsanforderungen für den Frequenzschutz

Relais de mesure et dispositifs de protection - Partie 181: Exigences fonctionnelles relatives aux protections de fréquence

IEC 60255-181:2019 spécifie les exigences minimales relatives à l'évaluation fonctionnelle et à l'évaluation de la performance des protections de fréquence. Le présent document définit également comment documenter et publier les résultats des essais de performance. Le présent document couvre les fonctions basées sur la mesure de fréquence ou la mesure de la dérivée de fréquence. Il couvre également la protection de fréquence lorsque des éléments de blocage complémentaires sont utilisés. Le présent document définit les facteurs d'influence qui affectent la précision dans des conditions de régime établi et les caractéristiques de performance dans des conditions dynamiques. Les méthodologies d'essai pour la vérification des caractéristiques de performance et de précision figurent également dans le présent document.

Merilni releji in zaščitna oprema - 181. del: Funkcijske zahteve za frekvenčno zaščito

General Information

• Status: Published
• Publication Date: 11-Apr-2019
• Withdrawal Date: 02-Apr-2022
• ICS: 29.120.70 - Relays
• Technical Committee: CLC/TC 95X - Measuring relays and protection equipment
• Drafting Committee: IEC/TC 95 - IEC_TC_95
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 12-Apr-2019
• Completion Date: 12-Apr-2019
• Ref Project: SIST EN IEC 60255-181:2020 - Measuring relays and protection equipment - Part 181: Functional requirements for frequency protection

Standards Content (Sample)

SLOVENSKI STANDARD
01-maj-2020
Merilni releji in zaščitna oprema - 181. del: Funkcijske zahteve za frekvenčno
zaščito
Measuring relays and protection equipment - Part 181: Functional requirements for
frequency protection
Ta slovenski standard je istoveten z: EN IEC 60255-181:2019
ICS:
29.120.70 Releji Relays
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 60255-181

NORME EUROPÉENNE
EUROPÄISCHE NORM
April 2019
ICS 29.120.70
English Version
Measuring relays and protection equipment - Part 181:
Functional requirements for frequency protection
(IEC 60255-181:2019)
Relais de mesure et dispositifs de protection - Partie 181: Messrelais und Schutzeinrichtungen - Teil 181:
Exigences fonctionnelles relatives aux protections de Funktionsanforderungen für den Frequenzschutz
fréquence (IEC 60255-181:2019)
(IEC 60255-181:2019)
This European Standard was approved by CENELEC on 2019-04-03. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden,
Switzerland, Turkey and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2019 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 60255-181:2019 E

European foreword
The text of document 95/402/FDIS, future edition 1 of IEC 60255-181, prepared by IEC/TC 95
"Measuring relays and protection equipment" was submitted to the IEC-CENELEC parallel vote and
approved by CENELEC as EN IEC 60255-181:2019.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2020-01-03
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2022-04-03
document have to be withdrawn
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.

Endorsement notice
The text of the International Standard IEC 60255-181:2019 was approved by CENELEC as a
European Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards
indicated:
IEC 60255-24 NOTE Harmonized as EN 60255-24
IEC 61000-2-4:2002 NOTE Harmonized as EN 61000-2-4:2002 (not modified)
IEC 61850-7-4 NOTE Harmonized as EN 61850-7-4
IEC 61850-9-2 NOTE Harmonized as EN 61850-9-2
IEC 61869-9:2016 NOTE Harmonized as EN 61869-9:— (not modified)

Under preparation. Stage at time of publication: FprEN 61869-9:2016.
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments)
applies.
NOTE 1  Where an International Publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
NOTE 2  Up-to-date information on the latest versions of the European Standards listed in this annex is available here:
www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60050-103 -  International Electrotechnical Vocabulary - - -
Part 103: Mathematics - Functions
IEC 60050-447 -  International Electrotechnical Vocabulary - - -
Part 447: Measuring relays
IEC 60050-601 -  International Electrotechnical Vocabulary. - -
Chapter 601: Generation, transmission and
distribution of electricity - General
IEC 60255-1 -  Measuring relays and protection equipment EN 60255-1 -
- Part 1: Common requirements
IEC 61850 series Communication networks and systems for EN 61850 series
power utility automation
IEC 61869 series Instrument transformers EN 61869 series

IEC 60255-181 ®
Edition 1.0 2019-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Measuring relays and protection equipment –

Part 181: Functional requirements for frequency protection

Relais de mesure et dispositifs de protection –

Partie 181: Exigences fonctionnelles relatives aux protections de fréquence

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.120.70 ISBN 978-2-8322-6496-6

– 2 – IEC 60255-181:2019 © IEC 2019
CONTENTS
FOREWORD . 6
1 Scope . 8
2 Normative references . 9
3 Terms and definitions . 9
4 Specification of the function . 13
4.1 General . 13
4.2 Input energizing quantities / energizing quantities . 13
4.3 Binary input signals . 14
4.4 Functional logic . 14
4.4.1 Operating characteristics . 14
4.4.2 Reset characteristics . 17
4.5 Additional influencing functions/conditions . 18
4.5.1 General . 18
4.5.2 Specific characteristics for under/over frequency function . 18
4.5.3 Specific characteristics for rate of change of frequency (ROCOF)
function . 19
4.6 Binary output signals . 19
4.6.1 General . 19
4.6.2 Start (pick-up) signal . 19
4.6.3 Operate (trip) signal . 19
4.6.4 Other binary output signals . 19
5 Performance specification . 20
5.1 General . 20
5.2 Effective and operating ranges . 20
5.3 Accuracy related to the characteristic quantity . 21
5.4 Start time for under/over frequency function . 21
5.5 Start time for rate of change of frequency (ROCOF) function . 21
5.6 Accuracy related to the operate time delay setting . 22
5.7 Disengaging time . 22
5.8 Reset hysteresis and reset ratio . 22
5.9 Accuracy related to restraint/blocking elements . 23
5.10 Performance with harmonics . 23
5.11 Stability in case of sudden voltage change (phase shift and magnitude shift) . 23
5.12 Voltage input requirements . 23
6 Functional test methodology . 24
6.1 General . 24
6.2 Determination of steady state errors related to the characteristic quantity . 26
6.2.1 Accuracy of the start value . 26
6.2.2 Reset hysteresis or reset ratio determination . 32
6.3 Determination of the start time . 41
6.3.1 General . 41
6.3.2 Under/over frequency . 41
6.3.3 Rate of change of frequency . 47
6.4 Determination of the accuracy of the operate time delay . 50
6.4.1 General . 50
6.4.2 Description of test method . 50
6.4.3 Reporting of the operate time delay accuracy . 52

IEC 60255-181:2019 © IEC 2019 – 3 –
6.5 Determination of disengaging time . 53
6.5.1 General . 53
6.5.2 Under/over frequency . 53
6.5.3 Rate of change of frequency . 56
6.6 Performance with harmonics . 58
6.6.1 General . 58
6.6.2 Accuracy of the under/over frequency start value in the presence of
harmonics . 58
6.6.3 Accuracy of the ROCOF start value in the presence of harmonics . 63
6.7 Stability in the case of sudden voltage change (phase shift and magnitude
change) . 65
6.7.1 General . 65
6.7.2 Performance in case of voltage phase shift and magnitude change . 65
6.7.3 Performance in case of voltage magnitude drop and restoration . 68
7 Documentation requirements . 70
7.1 Type test report . 70
7.2 Other user documentation . 71
Annex A (normative) Test signal equation with constant frequency variation (df/dt) . 72
Annex B (normative) Calculation of mean, median and mode . 73
B.1 Mean . 73
B.2 Median . 73
B.3 Mode .
...