SIST EN IEC 61400-21-1:2019
(Main)Wind energy generation systems - Part 21-1: Measurement and assessment of electrical characteristics - Wind turbines (IEC 61400-21-1:2019)
Wind energy generation systems - Part 21-1: Measurement and assessment of electrical characteristics - Wind turbines (IEC 61400-21-1:2019)
This part of IEC 61400 includes:
• definition and specification of the quantities to be determined for characterizing the
electrical characteristics of a grid-connected wind turbine;
• measurement procedures for quantifying the electrical characteristics;
• procedures for assessing compliance with electrical connection requirements, including
estimation of the power quality expected from the wind turbine type when deployed at a
specific site.
The measurement procedures are valid for single wind turbines with a three-phase grid
connection. The measurement procedures are valid for any size of wind turbine, though this
part of IEC 61400 only requires wind turbine types intended for connection to an electricity
supply network to be tested and characterized as specified in this part of IEC 61400.
The measured characteristics are valid for the specific configuration and operational mode of
the assessed wind turbine product platform. If a measured property is based on control
parameters and the behavior of the wind turbine can be changed for this property, it is stated
in the test report. Example: Grid protection, where the disconnect level is based on a
parameter and the test only verifies the proper functioning of the protection, not the specific
level.
The measurement procedures are designed to be as non-site-specific as possible, so that
electrical characteristics measured at for example a test site can be considered
representative for other sites.
This document is for the testing of wind turbines; all procedures, measurements and tests
related to wind power plants are covered by IEC 61400-21-2.
The procedures for assessing electrical characteristics are valid for wind turbines with the
connection to the PCC in power systems with stable grid frequency.
NOTE
For the purposes of this document, the following terms for system voltage apply:
– Low voltage (LV) refers to Un ≤ 1 kV;
– Medium voltage (MV) refers to 1 kV < Un ≤ 35 kV;
– High voltage (HV) refers to 35 kV < Un ≤ 220 kV;
– Extra high voltage (EHV) refers to Un > 220 kV.
Windenergieerzeugungsanlagen - Teil 21-1: Messung und Bewertung der elektrischen Kennwerte - Windenergieanlagen (IEC 61400-21-1:2019)
Systèmes de génération d'énergie éolienne - Partie 21-1: Mesurage et évaluation des caractéristiques électriques - Éoliennes (IEC 61400-21-1:2019)
l'IEC 61400-21-1:2019 comprend:
· la définition et la spécification des grandeurs à déterminer pour caractériser les caractéristiques électriques d'une éolienne connectée à un réseau;
· les procédures de mesure pour quantifier les caractéristiques électriques;
· les procédures pour évaluer la conformité aux exigences de raccordement électrique, y compris l'estimation de la qualité de puissance attendue d'un type d'éolienne, une fois déployée sur un site spécifique.
Les procédures de mesure sont valables pour les éoliennes individuelles avec un raccordement triphasé au réseau. Les procédures de mesure sont valables pour n'importe quelle taille d'éolienne; toutefois, la présente partie de l'IEC 61400 exige uniquement des types d'éoliennes prévues pour le raccordement à un réseau d'alimentation électrique, qui sont donc à soumettre aux essais et à caractériser comme spécifié dans la présente partie de l'IEC 61400.
Cette première édition annule et remplace la deuxième édition de l'IEC 61400-21 parue en 2008.
Cette édition inclut les nouveaux éléments suivants par rapport à l'IEC 61400-21:
a) mesure de contrôle de fréquence;
b) contrôle actualisé de la puissance réactive et de la mesure de la capacité, y compris le contrôle de la tension et contrôle du cos φ;
c) mesure de la réponse du contrôle d'inertie;
d) procédure d'essai du passage de surtension;
e) procédure d'essai du maintien de l'alimentation en sous-tension en fonction de la capacité des éoliennes actualisée;
f) nouvelles méthodes pour l'évaluation de l'harmonique.
Sistemi za proizvodnjo energije na veter - 21-1. del: Merjenje in ocenjevanje električnih karakteristik - Vetrne turbine (IEC 61400-21-1:2019)
Ta del standarda IEC 61400 vključuje:
• opredelitev in specifikacijo količin, ki jih je treba določiti za opis električnih karakteristik vetrne turbine, povezane z omrežjem;
• merilne postopke za količinsko opredelitev električnih karakteristik;
• postopke za oceno skladnosti z zahtevami za električno povezavo, vključno z oceno pričakovane kakovosti električne energije glede na vrsto vetrne turbine, ko je nameščena na določenem mestu.
Postopki merjenja veljajo za enojne vetrne turbine s trifaznim omrežnim priključkom. Postopki merjenja veljajo za poljubno velikost vetrne turbine, čeprav ta del standarda IEC 61400 zahteva le preskus in karakterizacijo vetrnih turbin v skladu s tem delom standarda IEC 61400, ki so namenjene za povezavo z električnim omrežjem.
Izmerjene karakteristike veljajo za specifično konfiguracijo in način delovanja ocenjevane platforme vetrnih turbin. Če izmerjena lastnost temelji na regulacijskih parametrih in se na podlagi spremembe te lastnosti spremeni delovanje vetrne turbine, je to navedeno v poročilu o preskusu. Primer: Zaščita omrežja, pri kateri raven odklopa temelji na parametru in preskus preveri zgolj pravilno delovanje zaščite, ne pa specifične ravni.
Postopki merjenja so zasnovani tako, da so čim manj odvisni od mesta namestitve, tako da je električne karakteristike, izmerjene na primer na preskusnem mestu, mogoče obravnavati kot reprezentativne tudi za druga mesta.
Ta dokument je namenjen preskušanju vetrnih turbin; vsi postopki, meritve in preskusi v zvezi z vetrnimi elektrarnami so zajeti v standardu IEC 61400-21-2.
Postopki za oceno električnih karakteristik veljajo za vetrne turbine s priključkom na PCC v elektroenergetskih sistemih z nespremenljivo frekvenco omrežja.
OPOMBA:
V tem dokumentu se uporabljajo naslednji izrazi za napetost v omrežju:
– nizka napetost (LV) označuje Un ≤ 1 kV;
– srednja napetost (MV) označuje 1 kV < Un ≤ 35 kV;
– visoka napetost (HV) označuje 35 kV < Un ≤ 220 kV;
– zelo visoka napetost (EHV) označuje Un > 220 kV.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN IEC 61400-21-1:2019
01-oktober-2019
Sistemi za proizvodnjo energije na veter - 21-1. del: Merjenje in ocenjevanje
električnih karakteristik - Vetrne turbine (IEC 61400-21-1:2019)
Wind energy generation systems - Part 21-1: Measurement and assessment of electrical
characteristics - Wind turbines (IEC 61400-21-1:2019)
Windenergieerzeugungsanlagen - Teil 21-1: Messung und Bewertung der elektrischen
Kennwerte - Windenergieanlagen (IEC 61400-21-1:2019)
Systèmes de génération d'énergie éolienne - Partie 21-1: Mesurage et évaluation des
caractéristiques électriques - Éoliennes (IEC 61400-21-1:2019)
Ta slovenski standard je istoveten z: EN IEC 61400-21-1:2019
ICS:
27.180 Vetrne elektrarne Wind turbine energy systems
SIST EN IEC 61400-21-1:2019 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN IEC 61400-21-1:2019
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SIST EN IEC 61400-21-1:2019
EUROPEAN STANDARD EN IEC 61400-21-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2019
ICS 27.180
English Version
Wind energy generation systems - Part 21-1: Measurement and
assessment of electrical characteristics - Wind turbines
(IEC 61400-21-1:2019)
Systèmes de génération d'énergie éolienne - Partie 21-1: Windenergieerzeugungsanlagen - Teil 21-1: Messung und
Mesurage et évaluation des caractéristiques électriques - Bewertung der elektrischen Kennwerte -
Éoliennes Windenergieanlagen
(IEC 61400-21-1:2019) (IEC 61400-21-1:2019)
This European Standard was approved by CENELEC on 2019-06-24. 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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, 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 61400-21-1:2019 E
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SIST EN IEC 61400-21-1:2019
EN IEC 61400-21-1:2019 (E)
European foreword
The text of document 88/711/FDIS, future edition 1 of IEC 61400-21-1, prepared by IEC/TC 88 "Wind energy
generation systems" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as
EN IEC 61400-21-1:2019.
The following dates are fixed:
• latest date by which the document has to be implemented at national level by (dop) 2020-03-24
publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2022-06-24
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 61400-21-1:2019 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following note has to be added for the standard indicated:
IEC 61400-27-1:2015 NOTE Harmonized as EN 61400-27-1:2015 (not modified)
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SIST EN IEC 61400-21-1:2019
EN IEC 61400-21-1:2019 (E)
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 61000-3-2 2014 Electromagnetic compatibility (EMC) - Part 3-2: Limits EN 61000-3-2 2014
- Limits for harmonic current emissions (equipment
input current ≤ 16 A per phase)
IEC 61000-3-3 - Electromagnetic compatibility (EMC) - Part 3-3: Limits EN 61000-3-3 -
- Limitation of voltage changes, voltage fluctuations
and flicker in public low-voltage supply systems, for
equipment with rated current < 16 A per phase and
not subject to conditional connection
IEC 61000-4-7 2002 Electromagnetic compatibility (EMC) - Part 4-7: EN 61000-4-7 2002
Testing and measurement techniques - General
guide on harmonics and interharmonics
measurements and instrumentation, for power supply
systems and equipment connected thereto
+ A1 2008 + A1 2009
IEC 61000-4-15 2010 Electromagnetic compatibility (EMC) - Part 4-15: EN 61000-4-15 2011
Testing and measurement techniques - Flickermeter -
Functional and design specifications
IEC 61000-4-30 - Electromagnetic compatibility (EMC) - Part 4-30: EN 61000-4-30 -
Testing and measurement techniques - Power quality
measurement methods
IEC 62008 - Performance characteristics and calibration methods EN 62008 -
for digital data acquisition systems and relevant
software
IEC/TR 61000- - Electromagnetic compatibility (EMC) - Part 3-6: Limits - -
3-6 - Assessment of emission limits for the connection of
distorting installations to MV, HV and EHV power
systems
IEC/TR 61000- - Electromagnetic compatibility (EMC) - Part 3-7: Limits - -
3-7:2008 - Assessment of emission limits for the connection of
fluctuating installations to MV, HV and EHV power
systems
IEC/TR 61000- - Electromagnetic compatibility (EMC) - Part 3-14: - -
3-14 Assessment of emission limits for harmonics,
interharmonics, voltage fluctuations and unbalance
for the connection of disturbing installations to LV
power systems
IEC/TR 61869- 2012 Instrument transformers - The use of instrument - -
103 transformers for power quality measurement
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SIST EN IEC 61400-21-1:2019
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SIST EN IEC 61400-21-1:2019
IEC 61400-21-1
®
Edition 1.0 2019-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Wind energy generation systems –
Part 21-1: Measurement and assessment of electrical characteristics – Wind
turbines
Systèmes de génération d'énergie éolienne –
Partie 21-1: Mesurage et évaluation des caractéristiques électriques – Éoliennes
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 27.180 ISBN 978-2-8322-6761-5
Warning! Make sure that you obtained this publication from an authorized distributor.
Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
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SIST EN IEC 61400-21-1:2019
– 2 – IEC 61400-21-1:2019 © IEC 2019
CONTENTS
FOREWORD . 10
INTRODUCTION . 12
1 Scope . 13
2 Normative references . 13
3 Terms and definitions . 14
4 Symbols and units . 25
5 Abbreviated terms . 26
6 Wind turbine specification . 27
7 Test conditions and test systems . 27
7.1 General . 27
7.2 Overview of required test levels . 27
7.3 Test validity . 28
7.4 Test conditions . 29
7.5 Test equipment . 30
8 Measurement and test of electrical characteristics . 32
8.1 General . 32
8.2 Power quality aspects . 32
8.2.1 General . 32
8.2.2 Flicker during continuous operation . 32
8.2.3 Flicker and voltage change during switching operations . 35
8.2.4 Harmonics, interharmonics and higher frequency components . 38
8.3 Steady-state operation . 40
8.3.1 General . 40
8.3.2 Observation of active power against wind speed . 40
8.3.3 Maximum power . 42
8.3.4 Reactive power characteristic (Q = 0) . 44
8.3.5 Reactive power capability . 44
8.3.6 Voltage dependency of PQ diagram . 45
8.3.7 Unbalance factor . 46
8.4 Control performance . 47
8.4.1 General . 47
8.4.2 Active power control . 47
8.4.3 Active power ramp rate limitation . 50
8.4.4 Frequency control . 52
8.4.5 Synthetic inertia . 54
8.4.6 Reactive power control . 55
8.5 Dynamic performance . 58
8.5.1 General . 58
8.5.2 Fault ride-through capability . 58
8.6 Disconnection from grid . 66
8.6.1 General . 66
8.6.2 Grid protection . 66
8.6.3 Test of rate of change of frequency RoCoF (df/dt) protection device . 70
8.6.4 Reconnection test . 71
Annex A (informative) Reporting . 72
A.1 Overview. 72
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A.2 General . 72
A.3 Power quality aspects . 74
A.4 Steady-state operation . 83
A.5 Dynamic performance (see 8.5) . 101
A.6 Disconnection from grid (see 8.6) . 106
Annex B (informative) Voltage fluctuations and flicker . 110
B.1 Continuous operation . 110
B.2 Switching operations . 110
B.3 Verification test of the measurement procedure for flicker . 111
B.3.1 General . 111
B.3.2 Fictitious grid performance testing . 112
B.3.3 Distorted u (t) voltage with multiple zero crossings . 113
m
B.3.4 Distorted u (t) voltage with inter-harmonic modulation . 113
m
B.3.5 Slow frequency changes . 114
B.4 Deduction of definitions. 114
B.4.1 Flicker coefficient . 114
B.4.2 Flicker step factor . 115
B.4.3 Voltage change factor . 116
Annex C (normative) Measurement of active power, reactive power and voltage . 117
C.1 General . 117
C.2 Generator convention of the signs . 117
C.3 Calculation of positive, negative and zero sequence quantities . 118
C.3.1 Phasor calculations . 118
C.3.2 Calculation of the positive sequence quantities using phasor
components . 121
C.3.3 Calculation of the negative sequence quantities using phasor
components . 122
C.3.4 Calculation of the zero sequence quantities using phasor components . 123
Annex D (informative) Harmonic evaluation . 125
D.1 General . 125
D.2 General analysis methods . 125
D.2.1 General . 125
D.2.2 Harmonic voltages . 125
D.2.3 Harmonic phase angles and magnitudes . 125
D.2.4 Statistical analysis . 129
D.2.5 Sample rate adjustment . 129
D.2.6 Determination of background harmonic voltage distortion . 129
D.2.7 Diurnal variations of the harmonic voltage and current . 129
D.2.8 Shutting down neighbouring WT or loads . 130
D.2.9 Harmonics of current and voltage over power . 130
D.2.10 Filters switching . 131
D.2.11 Measuring at a standard source . 132
D.2.12 Harmonics power flow + voltage measurement, phase angle . 132
D.2.13 Voltage harmonics with and without operation of the tested wind turbine . 133
D.2.14 Measurements at different sites . 134
D.2.15 Harmonic model. 134
D.3 Determination of harmonic amplitude affected by space harmonics at DFAG
systems . 134
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Annex E (informative) Assessment of power quality of wind turbines and wind power
plants. 136
E.1 General . 136
E.2 Voltage fluctuations . 136
E.2.1 General . 136
E.2.2 Continuous operation . 137
E.2.3 Switching operations . 137
E.3 Current harmonics, interharmonics and higher frequency components . 138
Annex F (informative) Guidelines for the transferability of test results to different
turbine variants in the same product platform . 140
Bibliography . 144
Figure 1 – Example of step response . 22
Figure 2 – Measurement system description including the most significant components . 31
Figure 3 – Fictitious grid for simulation of fictitious voltage . 33
Figure 4 – Active power as a function of the wind speed (example) . 41
Figure 5 – Number of measurements in power bins (example) . 42
Figure 6 – Number of measurements in wind speed bins (example) . 42
Figure 7 – Example of PQ capability diagram for a given voltage at WT level . 45
Figure 8 – Adjustment of active power reference value . 48
Figure 9 – Example of active power response step . 48
Figure 10 – Example of available active power and active power in ramp rate limitation
modefigue . 51
Figure 11 – Example of an active power control function P=f(f), with the different
measurement points and related steps of frequency . 52
Figure 12 – Synthetic inertia – definitions . 55
Figure 13 – Test for static error . 56
Figure 14 – Test of dynamic response (example) . 57
Figure 15 – Example UVRT test equipment . 59
Figure 16 – Tolerances of the positive sequence voltage for the undervoltage event
with disconnected WT under test . 60
Figure 17 – Tolerance of positive sequence overvoltage event. 61
Figure 18 – Example OVRT capacitor test unit . 62
Figure 19 – Example of an undervoltage test chart . 63
Figure 20 – Example of an overvoltage capability curve . 64
Figure 21 – Example of step ramp for overvoltage or frequency testing . 68
Figure 22 – Example of pulse ramp for over voltage or frequency testing . 69
Figure 23 – Example of the test levels to determine the release time . 69
Figure A.1 – Voltage flicker P vs. active power . 74
st
Figure A.2 – Flicker coefficient c(30°) vs. active power . 74
Figure A.3 – Flicker coefficient c(50°) vs. active power . 75
Figure A.4 – Flicker coefficient c(70°) vs. active power . 75
Figure A.5 – Flicker coefficient c(85°) vs. active power . 75
Figure A.6 – Time series of 3-phase voltages as RMS of start-up at the wind speed
of … m/s . 76
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Figure A.7 – Time series of 3-phase currents as RMS of start-up at the wind speed
of … m/s . 76
Figure A.8 – Time series of active and reactive power of start-up at the wind speed
of … m/s . 76
Figure A.9 – Time series of 3-phase voltages as RMS of start-up at the wind speed
of … m/s . 77
Figure A.10 – Time series of 3-phase currents as RMS of start-up at the wind speed
of … m/s . 77
Figure A.11 – Time series of active and reactive power of start-up at the wind speed
of … m/s . 77
Figure A.12 – Time series of 3-phase voltages as RMS of change from generator stage
1 to stage 2. 78
Figure A.13 – Time series of 3-phase currents as RMS of change from generator stage
1 to stage 2. 78
Figure A.14 – Time series of active and reactive power of change from generator stage
1 to stage 2. 78
Figure A.15 – Time series of 3-phase voltages as RMS of change from generator stage
2 to stage 1. 78
Figure A.16 – Time series of 3-phase currents as RMS of change from generator stage
2 to stage 1. 78
Figure A.17 – Time series of active and reactive power of change from generator stage
2 to stage 1. 79
th
Figure A.18 – Max. of the 95 percentiles of integer harmonic currents vs. harmonic
order . 83
th
Figure A.19 – Max. of the 95 percentiles of interharmonic currents vs. frequency. 83
th
Figure A.20 – Max. of the 95 percentiles of higher frequency current components vs.
frequency . 83
Figure A.21 – Active power as a function of the wind speed . 84
Figure A.22 – Reactive power vs. active power . 85
Figure A.23 – PQ-Diagram . 86
Figure A.24 – PQ-Diagram . 87
Figure A.25 – PQ-Diagram . 88
Figure A.26 – Mean 1-min current unbalance factor over active power . 89
Figure A.27 – Time-series of active power reference values, available power and
measured active power output during active power control for the evaluation of the
static error . 89
Figure A.28 – Time-series of measured wind speed during active power control during
the test of the static error . 89
Figure A.29 – Time-series of active power reference values, available power and
measured active power output during active power control for the evaluation of the
settling time . 90
Figure A.30 – Time-series of available and measured active power output during ramp
rate limitation . 90
Figure A.31 – Time-series of measured wind speed during ramp rate limitation . 91
Figure A.32 – Time-series of available and measured active power output during ramp
rate limitation . 91
Figure A.33 – Time-series
...
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