IEC_TS_61724-2-2016.pdf

IEC TS 61724-2 Edition 1.0 2016-10 TECHNICAL SPECIFICATION Photovoltaic system performance Part 2:Capacity evaluation method IEC TS 61724-2:2016-10(en)THIS PUBLICATION IS COPYRIGHT PROTECTED Copyright 2016 IEC,Geneva,Switzerland All rights reserved.Unless otherwise specified,no part of this publication may be reproduced or utilized in any form or by any means,electronic or mechanical,including photocopying and microfilm,without permission in writing from either IEC or IECs member National Committee in the country of the requester.If you have any questions about IEC copyright or have an enquiry about obtaining additional rights to this publication,please contact the address below or your local IEC member National Committee for further information.IEC Central Office Tel.:+41 22 919 02 11 3,rue de Varemb Fax:+41 22 919 03 00 CH-1211 Geneva 20 infoiec.ch Switzerland www.iec.ch About the IEC The International Electrotechnical Commission(IEC)is the leading global organization that prepares and publishes International Standards for all electrical,electronic and related technologies.About IEC publications The technical content of IEC publications is kept under constant review by the IEC.Please make sure that you have the latest edition,a corrigenda or an amendment might have been published.IEC Catalogue-webstore.iec.ch/catalogue The stand-alone application for consulting the entire bibliographical information on IEC International Standards,Technical Specifications,Technical Reports and other documents.Available for PC,Mac OS,Android Tablets and iPad.IEC publications search-www.iec.ch/searchpub The advanced search enables to find IEC publications by a variety of criteria(reference number,text,technical committee,).It also gives information on projects,replaced and withdrawn publications.IEC Just Published-webstore.iec.ch/justpublished Stay up to date on all new IEC publications.Just Published details all new publications released.Available online and also once a month by email.Electropedia-www.electropedia.org The worlds leading online dictionary of electronic and electrical terms containing 20 000 terms and definitions in English and French,with equivalent terms in 15 additional languages.Also known as the International Electrotechnical Vocabulary(IEV)online.IEC Glossary-std.iec.ch/glossary 65 000 electrotechnical terminology entries in English and French extracted from the Terms and Definitions clause of IEC publications issued since 2002.Some entries have been collected from earlier publications of IEC TC 37,77,86 and CISPR.IEC Customer Service Centre-webstore.iec.ch/csc If you wish to give us your feedback on this publication or need further assistance,please contact the Customer Service Centre:csciec.ch.IEC TS 61724-2 Edition 1.0 2016-10 TECHNICAL SPECIFICATION Photovoltaic system performance Part 2:Capacity evaluation method INTERNATIONAL ELECTROTECHNICAL COMMISSION ICS 27.160 ISBN 978-2-83223-664-2 Registered trademark of the International Electrotechnical Commission Warning!Make sure that you obtained this publication from an authorized distributor.2 IEC TS 61724-2:2016 IEC 2016 CONTENTS FOREWORD.4 INTRODUCTION.6 1 Scope.7 2 Normative references.7 3 Terms and definitions.8 4 Test scope,schedule and duration.10 5 Equipment and measurements.11 6 Procedure.12 6.1 Documentation of the performance targets under“unconstrained”and“constrained”operation.12 6.1.1 General.12 6.1.2 Definition of test boundary to align with intended system boundary.12 6.1.3 Definition of the reference conditions for“unconstrained”operation.12 6.1.4 Definition of the performance target under“unconstrained”and“constrained”operation.13 6.1.5 Definition of the temperature dependence of the plant output under“unconstrained”operation.13 6.1.6 Definition of irradiance dependence.14 6.1.7 Definition of the performance target under“constrained”operation.14 6.1.8 Uncertainty definition.14 6.2 Measurement of data.14 6.2.1 General.14 6.2.2 Data checks for each data stream.15 6.2.3 Shading of irradiance sensor.16 6.2.4 Calibration accuracy.16 6.2.5 Using data from multiple sensors.16 6.2.6 Unconstrained operation and constrained operation when the output limit of the inverter is reached.17 6.3 Calculation of correction factor.17 6.3.1 General.17 6.3.2 Measure inputs.17 6.3.3 Verify data quality.17 6.3.4 Calculate the correction factor for each measurement point.17 6.3.5 Correct measured power output.18 6.3.6 Average all values of corrected power.18 6.3.7 Analyse discrepancies.18 6.4 Comparison of measured power with the performance target.18 6.5 Uncertainty analysis.19 7 Test procedure documentation.20 8 Test report.21 Annex A(informative)Example of model for module temperature calculations.22 A.1 General.22 A.2 Example heat transfer model to calculate expected cell operating temperature.22 Annex B(informative)Example of model for system power.25 B.1 General.25 IEC TS 61724-2:2016 IEC 2016 3 B.2 Example model.25 Annex C(informative)Inconsistent arr