SIST EN IEC 61400-21-2:2023
(Main)Wind energy generation systems - Part 21-2: Measurement and assessment of electrical characteristics - Wind power plants (IEC 61400-21-2:2023)
Wind energy generation systems - Part 21-2: Measurement and assessment of electrical characteristics - Wind power plants (IEC 61400-21-2:2023)
IEC 61400-21-2 - Wind energy generation systems - Measurement and assessment of electrical characteristics - Wind power plants - has the following scope: IEC 61400-21-2 defines and specifies the quantities that shall be determined to characterize the electrical characteristics of grid-connected power plants (PP).
IEC 61400-21-2 defines the measurement and test procedures for quantifying the electrical characteristics as basis for the verification of compliance of PP, including:
- Power quality aspects
- Steady state operation
- Dynamic response (undervoltage and overvoltage fault ride-through)
- Disconnection from grid (Grid protection)
- Control performance
IEC 61400-21-2 defines a uniform functionality test and measurement procedure for the power plant controller (PPC), as a basis for the unit test of the power plant controller.
IEC 61400-21-2 defines the procedures for assessing compliance with electrical connection requirements, including the aggregation methods for power quality aspects such as voltage variations, flicker, harmonics and interharmonics.
IEC 61400-21-2 defines the procedures for measurement and fault recording for the verification of power plant electrical simulation models in relation to undervoltage and overvoltage ride through events.
These measurement procedures are valid for power plants, including the power plant controller and other connected equipment, necessary for the operation of the Power Plant. The measurement procedures are valid for any size of power plant connected to the point of connection (POC) at one connection point.
The procedures for assessing and verifying the compliance with grid connection requirements are valid for power plants in power systems with fixed frequency and a sufficient short-circuit power.
Out of the scope of this standard are:
- Multi park control, i.e. cluster management of several power plants (PP) or several connection points
- Compliance test and performance requirements, including pass or fail criteria
- Specific component test and validation of the PP equipment (switchgear, cables, transformers, etc.), which are covered by other IEC standards
- Wind power plant model validation, as defined in the IEC 61400-27-2
- Load flow calculation methods and load flow study guidelines
- Test and measurement of the communication interface and system of the PP as defined in the IEC 61400-25 series
NOTE
For the purposes of this document, the following terms for system voltage apply, based on IEC 60038
Low voltage (LV) refers to 100 V < Un ≤ 1 kV;
Medium voltage (MV) refers 106 to 1 kV < Un ≤ 35 kV;
High voltage (HV) refers to 35 kV < Un ≤ 230 kV;
Extra high voltage (EHV) refers to Un > 230 kV
Windenergieerzeugungsanlagen - Teil 21-2: Messung und Bewertung der elektrischen Kennwerte - Windkraftwerke (IEC 61400-21-2:2023)
Systèmes de génération d'énergie éolienne - Partie 21-2: Mesurage et évaluation des caractéristiques électriques - Centrales éoliennes (IEC 61400-21-2:2023)
l'IEC 61400-21-2:2023 définit et spécifie les grandeurs qui sont déterminées pour définir les caractéristiques électriques des centrales électriques (PP) connectées au réseau.l'IEC 61400 définit et spécifie les grandeurs qui sont déterminées pour définir les caractéristiques électriques des centrales électriques (PP) connectées au réseau.
Le présent document définit une procédure de mesure et d'essai de fonctionnalité uniforme pour le contrôleur de centrale électrique (PPC), qui sert de base pour l'essai d'unité du contrôleur de centrale électrique.
Le présent document définit les procédures d'évaluation de la conformité aux exigences de raccordement électrique, y compris les méthodes d'agrégation pour les aspects liés à la qualité de puissance, tels que les variations de tension, le papillotement, les harmoniques et les interharmoniques.
Le présent document définit les procédures de mesure et d'enregistrement des défaillances, par exemple pour la vérification des modèles de simulation électrique de centrale en ce qui concerne les événements d'alimentation continue en cas de sous-tension et de surtension.
Sistemi za proizvodnjo energije na veter - 21-2. del: Merjenje in ocenjevanje električnih karakteristik - Vetrne elektrarne (IEC 61400-21-2:2023)
Področje uporabe standarda IEC 61400-21-2 - Sistemi za proizvodnjo energije na veter - Merjenje in ocenjevanje električnih karakteristik - Vetrne elektrarne zajema naslednje: standard IEC 61400-21-2 opredeljuje in določa količine, ki jih je treba določiti za opredelitev električnih karakteristik elektrarn, priklopljenih na omrežje (PP).
Standard IEC 61400-21-2 opredeljuje postopke merjenja in preskusne postopke za količinsko določanje električnih karakteristik kot osnovo za preverjanje skladnosti elektrarn, priklopljenih na omrežje, vključno s/z:
– vidiki kakovosti električne energije;
– delovanjem v ravnotežnem stanju;
– dinamično odzivnostjo (obratovanje pri podnapetosti in prenapetosti zaradi okvare);
– izklopom iz omrežja (zaščita omrežja);
– nadzorom delovanja.
Standard IEC 61400-21-2 opredeljuje enotni preskus funkcionalnosti in postopek merjenja za krmilnik elektrarne (PPC) kot osnovo za preskus enote krmilnika elektrarne.
Standard IEC 61400-21-2 opredeljuje postopke za ocenjevanje skladnosti z zahtevami v zvezi z električno povezavo, vključno z metodami združevanja za vidike kakovosti električne energije, kot so napetostno kolebanje, nihanje, harmoniki in medharmoniki.
Standard IEC 61400-21-2 opredeljuje postopke za merjenje in zapisovanje napak za preverjanje simulacijskih električnih modelov elektrarne v zvezi z obratovanjem pri podnapetosti in prenapetosti zaradi okvare.
Ti postopki merjenja veljajo za elektrarne, vključno s krmilnikom elektrarne in drugo povezano opremo, ki je potrebna za delovanje elektrarne. Postopki merjenja veljajo za elektrarne vseh velikosti, ki so povezane s točko povezave (POC) na eni priključni točki.
Postopki za ocenjevanje in preverjanje skladnosti z zahtevami omrežne priključitve veljajo za elektrarne v električnih omrežjih s fiksno frekvenco in zadostno kratkostično močjo.
Področje uporabe tega standarda ne zajema:
– upravljanja grozdov več elektrarn, priklopljenih na omrežje, ali več priključnih točk (»multi park control«);
– preskusa skladnosti in zahtev glede učinkovitosti, vključno z merili za uspešnost in neuspešnost;
– preskusa posebnih komponent in potrjevanja opreme elektrarn, priklopljenih na omrežje (stikalne naprave, kabli, transformatorji itd.), kar je zajeto v drugih standardih IEC;
– potrjevanja modela vetrne elektrarne, kot je opredeljeno v standardu IEC 61400-27-2;
– metod za izračun pretokov moči in smernic za njihovo preučevanje;
– preskusa in merjenja komunikacijskega vmesnika in sistema elektrarn, priklopljenih na omrežje, kot je opredeljeno v skupini standardov IEC 61400-25.
OPOMBA:
V tem dokumentu se za napetost v omrežju uporabljajo naslednji izrazi (na podlagi standarda IEC 60038):
nizka napetost (LV) v razponu 100 V < Un ≤ 1 kV;
srednja napetost (MV) v razponu 1 kV < Un ≤ 35 kV;
visoka napetost (HV) v razponu 35 kV < Un ≤ 230 kV;
zelo visoka napetost (EHV) v razponu Un > 230 kV.
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN IEC 61400-21-2:2023
01-julij-2023
Sistemi za proizvodnjo energije na veter - 21-2. del: Merjenje in ocenjevanje
električnih karakteristik - Vetrne elektrarne (IEC 61400-21-2:2023)
Wind energy generation systems - Part 21-2: Measurement and assessment of electrical
characteristics - Wind power plants (IEC 61400-21-2:2023)
Windenergieerzeugungsanlagen - Teil 21-2: Messung und Bewertung der elektrischen
Kennwerte - Windkraftwerke (IEC 61400-21-2:2023)
Systèmes de génération d'énergie éolienne - Partie 21-2: Mesurage et évaluation des
caractéristiques électriques - Centrales éoliennes (IEC 61400-21-2:2023)
Ta slovenski standard je istoveten z: EN IEC 61400-21-2:2023
ICS:
27.180 Vetrne elektrarne Wind turbine energy systems
SIST EN IEC 61400-21-2:2023 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN IEC 61400-21-2:2023
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SIST EN IEC 61400-21-2:2023
EUROPEAN STANDARD EN IEC 61400-21-2
NORME EUROPÉENNE
EUROPÄISCHE NORM May 2023
ICS 27.180
English Version
Wind energy generation systems - Part 21-2: Measurement and
assessment of electrical characteristics - Wind power plants
(IEC 61400-21-2:2023)
Systèmes de génération d'énergie éolienne - Partie 21-2: Windenergieanlagen - Teil 21-2: Messung und Bewertung
Mesurage et évaluation des caractéristiques électriques - der elektrischen Kennwerte - Windkraftwerke
Centrales éoliennes (IEC 61400-21-2:2023)
(IEC 61400-21-2:2023)
This European Standard was approved by CENELEC on 2023-05-03. 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, 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,
Türkiye 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
© 2023 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 61400-21-2:2023 E
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SIST EN IEC 61400-21-2:2023
EN IEC 61400-21-2:2023 (E)
European foreword
The text of document 88/933/FDIS, future edition 1 of IEC 61400-21-2, prepared by IEC/TC 88 "Wind
energy generation systems" was submitted to the IEC-CENELEC parallel vote and approved by
CENELEC as EN IEC 61400-21-2:2023.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2024-02-03
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2026-05-03
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.
Any feedback and questions on this document should be directed to the users’ national committee. A
complete listing of these bodies can be found on the CENELEC website.
Endorsement notice
The text of the International Standard IEC 61400-21-2:2023 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 standard indicated:
IEC 60255 (series) NOTE Approved as EN 60255 (series)
IEC 61000 (series) NOTE Approved as EN IEC 61000 (series)
IEC 61000-4-7 NOTE Approved as EN 61000-4-7
IEC 61400-25 (series) NOTE Approved as EN 61400-25 (series)
IEC 61400-25-1 NOTE Approved as EN 61400-25-1
IEC 61800-3 NOTE Approved as EN IEC 61800-3
IEC 61850-9-2 NOTE Approved as EN 61850-9-2
IEC 62008 NOTE Approved as EN 62008
2
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SIST EN IEC 61400-21-2:2023
EN IEC 61400-21-2:2023 (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.cencenelec.eu.
Publication Year Title EN/HD Year
IEC 60038 - IEC standard voltages EN 60038 -
IEC 60255-121 2014 Measuring relays and protection equipment EN 60255-121 2014
- Part 121: Functional requirements for
distance protection
IEC 60255-127 2010 Measuring relays and protection equipment EN 60255-127 2014
- Part 127: Functional requirements for
over/under voltage protection
IEC 60255-151 2009 Measuring relays and protection equipment EN 60255-151 2009
- Part 151: Functional requirements for
over/under current protection
IEC 60255-181 2019 Measuring relays and protection equipment EN IEC 60255-181 2019
- Part 181: Functional requirements for
frequency protection
IEC/TR 61000-3-6 - Electromagnetic compatibility (EMC) - Part - -
3-6: Limits - Assessment of emission limits
for the connection of distorting installations
to MV, HV and EHV power systems
IEC 61000-4-15 - Electromagnetic compatibility (EMC) - Part EN 61000-4-15 -
4-15: Testing and measurement
techniques - Flickermeter - Functional and
design specifications
IEC 61000-4-30 - Electromagnetic compatibility (EMC) - Part EN 61000-4-30 -
4-30: Testing and measurement
techniques - Power quality measurement
methods
IEC 61400-21-1 2019 Wind energy generation systems - Part 21- EN IEC 61400-21-1 2019
1: Measurement and assessment of
electrical characteristics - Wind turbines
- - + A11 2020
IEC 61400-27-1 - Wind energy generation systems - Part 27- EN IEC 61400-27-1 -
1: Electrical simulation models - Generic
models
3
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SIST EN IEC 61400-21-2:2023
EN IEC 61400-21-2:2023 (E)
IEC 61400-27-2 - Wind energy generation systems - Part 27- EN IEC 61400-27-2 -
2: Electrical simulation models - Model
validation
IEC 61869-2 - Instrument transformers - Part 2: Additional EN 61869-2 -
requirements for current transformers
IEC 61869-3 - Instrument transformers - Part 3: Additional EN 61869-3 -
requirements for inductive voltage
transformers
IEC/IEEE 61850-9-3 - Communication networks and systems for - -
power utility automation - Part 9-3:
Precision time protocol profile for power
utility automation
4
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SIST EN IEC 61400-21-2:2023
IEC 61400-21-2
®
Edition 1.0 2023-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Wind energy generation systems –
Part 21-2: Measurement and assessment of electrical characteristics – Wind
power plants
Systèmes de génération d'énergie éolienne –
Partie 21-2: Mesurage et évaluation des caractéristiques électriques – Centrales
éoliennes
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
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ELECTROTECHNIQUE
INTERNATIONALE
ICS 27.180 ISBN 978-2-8322-6648-9
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 61400-21-2:2023
– 2 – IEC 61400-21-2:2023 © IEC 2023
CONTENTS
FOREWORD . 9
INTRODUCTION . 11
1 Scope . 13
2 Normative references . 14
3 Terms and definitions . 15
4 Symbols and abbreviated terms . 25
4.1 Symbols . 25
4.2 Abbreviated terms . 27
5 Power plant specifications . 27
6 Overall test and documentation requirements . 29
6.1 General . 29
6.2 Test conditions, monitoring and reporting requirements . 31
6.3 Test conditions in the case of external influences . 33
6.4 Test and measurement equipment . 33
6.4.1 General . 33
6.4.2 Voltage, current and power calculations . 33
6.4.3 Measurement equipment . 33
6.4.4 Existing measurement equipment for power control tests . 34
6.4.5 Optional measurements . 34
6.5 Functional and performance test . 34
6.6 Power plant controller . 35
6.6.1 General . 35
6.6.2 Definition and requirements . 35
6.6.3 Measurement points . 36
6.6.4 Measurement data . 37
6.6.5 Test setup . 37
6.6.6 Documentation . 38
7 Measurement and test of electrical characteristics . 39
7.1 General . 39
7.2 Power quality aspects . 39
7.2.1 General . 39
7.2.2 Flicker during continuous operation . 39
7.2.3 Rapid voltage changes due to switching operations . 40
7.2.4 Harmonics . 41
7.3 Steady state operation . 43
7.3.1 General . 43
7.3.2 Unbalance . 43
7.4 Dynamic performance . 44
7.4.1 Undervoltage and overvoltage ride-through (UVRT and OVRT)
capability . 44
7.4.2 Test setup and test conditions . 44
7.4.3 Test and measurement procedure . 44
7.4.4 Documentation . 46
7.5 Disconnection from grid . 47
7.5.1 Grid protection . 47
7.5.2 Requirements of test devices . 48
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7.5.3 Grid protection test – PP level . 48
7.5.4 Grid protection test – PGU level . 49
7.5.5 RoCoF . 49
8 Control performance . 49
8.1 General . 49
8.2 Performance test . 49
8.2.1 General . 49
8.2.2 Active power control tests . 50
8.2.3 Controlled shutdown . 52
8.2.4 Synthetic inertia response . 54
8.2.5 Reactive power control . 57
8.2.6 Reactive power capability . 60
8.3 Functionality tests . 63
8.3.1 General . 63
8.3.2 Active power ramp rate limitation test . 63
8.3.3 Priority of setpoints . 65
8.3.4 Frequency control . 67
8.3.5 Reactive power ramp rate limitation . 72
8.3.6 Voltage control Q(U)-characteristic . 76
8.3.7 Power factor control . 78
8.3.8 Communication error/fallback scenarios . 81
9 Assessment of power quality of power plants (PP) . 84
9.1 General . 84
9.2 Voltage fluctuations . 84
9.2.1 Voltage change . 84
9.2.2 Flicker in continuous operation . 85
9.2.3 Voltage change and flicker during switching operations . 86
9.3 Current harmonics, interharmonics and higher frequency components . 87
Annex A (informative) Report template . 89
A.1 Overview. 89
A.2 Power plant specification and test conditions . 89
A.3 Power plant controller . 90
A.4 Power quality aspects . 91
A.5 Steady state operation . 120
A.6 Dynamic performance . 121
A.7 Disconnection from grid (grid protection) . 122
A.8 Performance test . 122
A.8.1 General . 122
A.8.2 Static error test . 122
A.8.3 Dynamic response test . 123
A.8.4 Controlled shutdown . 123
A.8.5 Synthetic inertia response . 124
A.8.6 Reactive power control . 126
A.8.7 Reactive power capability . 127
A.9 Functionality tests . 128
A.9.1 Active power ramp rate limitation test . 128
A.9.2 Priority of setpoints . 129
A.9.3 Frequency control . 130
A.9.4 Reactive power ramp rate limitation . 131
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A.9.5 Voltage control Q(U)-characteristic . 132
A.9.6 Power factor control . 133
A.9.7 Communication error / fallback scenarios . 135
Annex B (informative) Harmonic evaluation . 137
B.1 Harmonic estimation at the point of interest . 137
B.2 Background harmonic distortion . 137
B.3 Harmonic summation . 138
B.4 Harmonic propagation studies . 138
B.5 PP harmonic contribution evaluation . 139
B.5.1 General . 139
B.5.2 Incremental PP harmonic contribution based on simulations . 139
B.5.3 PP electromagnetic compatibility analysis based on simulations . 139
B.5.4 Harmonic measurements at the POC . 140
Annex C (informative) Validation procedure for PP . 141
Annex D (informative) Measurement accuracy . 143
Bibliography . 146
Figure 1 – Example of step response . 19
Figure 2 – Example of a PP setup . 29
Figure 3 – General structure of a PPC for reactive power control within a power plant . 35
Figure 4 – General structure of a PPC for active power control within a power plant . 36
Figure 5 – Illustration of the PPC as a black box with in- and outputs . 36
Figure 6 – Illustration of the PPC with the internal system data . 37
Figure 7 – Illustration of a complete test setup . 38
Figure 8 – Example of time series for the active and reactive current measured (M)
and simulated (S) active and reactive current [1]. 47
Figure 9 – Adjustment of active power reference value . 51
Figure 10 – Example of active power response step . 51
Figure 11 – Example of controlled shutdown . 54
Figure 12 – Synthetic inertia – example response and definitions . 56
Figure 13 – Test for static error . 59
Figure 14 – Example of test of dynamic response . 59
Figure 15 – Example of test of reactive power capability QP-chart . 62
Figure 16 – Example of reactive power capability UP-chart corresponding to the QP-
chart . 62
Figure 17 – Example of available active power and active power in ramp rate limitation
mode . 64
Figure 18 – Example of active power setpoint prioritization test . 66
Figure 19 – PPC measured frequency feedback is replaced by a simulated frequency . 69
Figure 20 – Example of an active power control function P = f(f), with the different
measurement points and related steps of frequency . 70
Figure 21 – Example of reactive power ramp rate limitation test . 75
Figure 22 – Example of the Q(U) characteristic with a 4 % slope . 76
Figure 23 – Example of possible PP communication faults . 81
Figure 24 – Example of graph for communication error test. 83
Figure A.1 – Figure 25 – Voltage flicker P versus active power for normal operation . 91
st
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Figure A.2 – Voltage flicker P for background level . 92
st
Figure A.3 – Time series of three-phase voltages as RMS of PP starting . 92
Figure A.4 – Time series of three-phase currents as RMS of PP starting. 92
Figure A.5 – Time series of active and reactive power of PP starting . 92
Figure A.6 – Time series of three-phase voltages as RMS of PP stopping. 93
Figure A.7 – Time series of three-phase currents as RMS of PP stopping . 93
Figure A.8 – Time series of active and reactive power of PP stopping . 93
th
Figure A.9 – Maximum of the 99 percentiles of integer harmonic currents versus
harmonic order . 117
th
Figure A.10 – Maximum of the 99 percentiles of interharmonic currents versus
frequency . 117
th
Figure A.11 – Maximum of the 99 percentiles of higher frequency current
components versus frequency . 117
th
Figure A.12 – Maximum of the 95 percentiles of integer harmonic currents versus
harmonic order . 117
th
Figure A.13 – Maximum of the 95 percentiles of interharmonic currents versus
frequency . 118
th
Figure A.14 – Maximum of the 95 percentiles of higher frequency current
components versus frequency . 118
th
Figure A.15 – Maximum of the 99 percentiles of integer harmonic voltages versus
harmonic order . 118
th
Figure A.16 – Maximum of the 99 percentiles of interharmonic voltages versus
frequency . 118
th
Figure A.17 – Maximum of the 99 percentiles of higher frequency voltage
components versus frequency . 119
th
Figure A.18 – Maximum of the 95 percentiles of integer harmonic voltages versus
harmonic order . 119
th
Figure A.19 – Maximum of the 95 percentiles of interharmonic voltages versus
frequency . 119
th
Figure A.20 – Maximum of the 95 percentiles of higher frequency voltage
components versus frequency . 119
Figure A.21 – Current unbalance factor as a function of active power . 120
Figure A.22 – Voltage unbalance factor as a function of active power . 120
Figure A.23 – Time series: Instantaneous three-phase currents and voltages at the
POC . 121
Figure A.24 – Time series: Positive and negative sequence of the active and reactive
current . 121
Figure A.25 – Time series: Positive and negative sequence of the active and reactive
power . 121
Figure A.26 – Time series: Positive and negative sequence grid vol
...
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