1、 IEC 60904-5 Edition 2.0 2011-02 INTERNATIONAL STANDARD NORME INTERNATIONALE Photovoltaic devices Part 5: Determination of the equivalent cell temperature (ECT) of photovoltaic (PV) devices by the open-circuit voltage method Dispositifs photovoltaques Partie 5: Dtermination de la temprature de cellu
2、le quivalente (ECT) des dispositifs photovoltaques (PV) par la mthode de la tension en circuit ouvert IEC 60904-5:2011 THIS PUBLICATION IS COPYRIGHT PROTECTED Copyright 2011 IEC, Geneva, Switzerland All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or uti
3、lized 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 additio
4、nal rights to this publication, please contact the address below or your local IEC member National Committee for further information. Droits de reproduction rservs. Sauf indication contraire, aucune partie de cette publication ne peut tre reproduite ni utilise sous quelque forme que ce soit et par a
5、ucun procd, lectronique ou mcanique, y compris la photocopie et les microfilms, sans laccord crit de la CEI ou du Comit national de la CEI du pays du demandeur. Si vous avez des questions sur le copyright de la CEI ou si vous dsirez obtenir des droits supplmentaires sur cette publication, utilisez l
6、es coordonnes ci-aprs ou contactez le Comit national de la CEI de votre pays de rsidence. IEC Central Office 3, rue de Varemb CH-1211 Geneva 20 Switzerland Email: inmailiec.ch Web: www.iec.ch About the IEC The International Electrotechnical Commission (IEC) is the leading global organization that pr
7、epares 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
8、been published. Catalogue of IEC publications: www.iec.ch/searchpub The IEC on-line Catalogue enables you to search by a variety of criteria (reference number, text, technical committee,). It also gives information on projects, withdrawn and replaced publications. IEC Just Published: www.iec.ch/onli
9、ne_news/justpub Stay up to date on all new IEC publications. Just Published details twice a month all new publications released. Available on-line and also by email. Electropedia: www.electropedia.org The worlds leading online dictionary of electronic and electrical terms containing more than 20 000
10、 terms and definitions in English and French, with equivalent terms in additional languages. Also known as the International Electrotechnical Vocabulary online. Customer Service Centre: www.iec.ch/webstore/custserv If you wish to give us your feedback on this publication or need further assistance,
11、please visit the Customer Service Centre FAQ or contact us: Email: csciec.ch Tel.: +41 22 919 02 11 Fax: +41 22 919 03 00 A propos de la CEI La Commission Electrotechnique Internationale (CEI) est la premire organisation mondiale qui labore et publie des normes internationales pour tout ce qui a tra
12、it llectricit, llectronique et aux technologies apparentes. A propos des publications CEI Le contenu technique des publications de la CEI est constamment revu. Veuillez vous assurer que vous possdez ldition la plus rcente, un corrigendum ou amendement peut avoir t publi. Catalogue des publications d
13、e la CEI: www.iec.ch/searchpub/cur_fut-f.htm Le Catalogue en-ligne de la CEI vous permet deffectuer des recherches en utilisant diffrents critres (numro de rfrence, texte, comit dtudes,). Il donne aussi des informations sur les projets et les publications retires ou remplaces. Just Published CEI: ww
14、w.iec.ch/online_news/justpub Restez inform sur les nouvelles publications de la CEI. Just Published dtaille deux fois par mois les nouvelles publications parues. Disponible en-ligne et aussi par email. Electropedia: www.electropedia.org Le premier dictionnaire en ligne au monde de termes lectronique
15、s et lectriques. Il contient plus de 20 000 termes et dfinitions en anglais et en franais, ainsi que les termes quivalents dans les langues additionnelles. Egalement appel Vocabulaire Electrotechnique International en ligne. Service Clients: www.iec.ch/webstore/custserv/custserv_entry-f.htm Si vous
16、dsirez nous donner des commentaires sur cette publication ou si vous avez des questions, visitez le FAQ du Service clients ou contactez-nous: Email: csciec.ch Tl.: +41 22 919 02 11 Fax: +41 22 919 03 00 IEC 60904-5 Edition 2.0 2011-02 INTERNATIONAL STANDARD NORME INTERNATIONALE Photovoltaic devices
17、Part 5: Determination of the equivalent cell temperature (ECT) of photovoltaic (PV) devices by the open-circuit voltage method Dispositifs photovoltaques Partie 5: Dtermination de la temprature de cellule quivalente (ECT) des dispositifs photovoltaques (PV) par la mthode de la tension en circuit ouv
18、ert INTERNATIONAL ELECTROTECHNICAL COMMISSION COMMISSION ELECTROTECHNIQUE INTERNATIONALE K ICS 27.160 PRICE CODE CODE PRIX ISBN 978-2-88912-366-7 Registered trademark of the International Electrotechnical Commission Marque dpose de la Commission Electrotechnique Internationale 2 60904-5 IEC:2011 CON
19、TENTS FOREWORD . 3 INTRODUCTION . 5 1 Scope and object 6 2 Normative references . 6 3 Measurement principle and requirements . 6 3.1 Principle 6 3.2 General measurement requirements 7 4 Apparatus . 7 5 Determination of required input parameters 7 6 Procedure 8 6.1 General . 8 6.2 Operating in a cont
20、rolled environment . 8 6.3 Taking measurements under arbitrary irradiance conditions 8 7 Calculation of equivalent cell temperature 8 8 Test report 9 60904-5 IEC:2011 3 INTERNATIONAL ELECTROTECHNICAL COMMISSION _ PHOTOVOLTAIC DEVICES Part 5: Determination of the equivalent cell temperature (ECT) of
21、photovoltaic (PV) devices by the open-circuit voltage method FOREWORD 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international co
22、-operation on all questions concerning standardization in the electrical and electronic fields. To this end and in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred
23、to as “IEC Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with may participate in this preparatory work. International, governmental and non- governmental organizations liaising with the IEC also participate in thi
24、s preparation. IEC collaborates closely with the International Organization for Standardization (ISO) in accordance with conditions determined by agreement between the two organizations. 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an internationa
25、l consensus of opinion on the relevant subjects since each technical committee has representation from all interested IEC National Committees. 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National Committees in that sense. While all reasonable ef
26、forts are made to ensure that the technical content of IEC Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any misinterpretation by any end user. 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publica
27、tions transparently to the maximum extent possible in their national and regional publications. Any divergence between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter. 5) IEC itself does not provide any attestation of conformity. In
28、dependent certification bodies provide conformity assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any services carried out by independent certification bodies. 6) All users should ensure that they have the latest edition of this publication. 7) N
29、o liability shall attach to IEC or its directors, employees, servants or agents including individual experts and members of its technical committees and IEC National Committees for any personal injury, property damage or other damage of any nature whatsoever, whether direct or indirect, or for costs
30、 (including legal fees) and expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC Publications. 8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is indispensable for the correct applicat
31、ion of this publication. 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent rights. IEC shall not be held responsible for identifying any or all such patent rights. International Standard IEC 60904-5 has been prepared by IEC techni
32、cal committee 82: Solar photovoltaic energy systems. This second edition cancels and replaces the first edition, issued in 1993, and constitutes a technical revision. The main technical changes with regard to the previous edition are as follows: added and updated normative references; added reportin
33、g section; added method on how to extract the input parameters; rewritten method on how to calculate ECT; reworked formulae to be in line with IEC 60891. 4 60904-5 IEC:2011 The text of this standard is based on the following documents: CDV Report on voting 82/595/CDV 82/626/RVC Full information on t
34、he voting for the approval of this standard can be found in the report on voting indicated in the above table. A list of all parts of IEC 60904 series, under the general title Photovoltaic devices, can be found on the IEC website. This publication has been drafted in accordance with the ISO/IEC Dire
35、ctives, Part 2. The committee has decided that the contents of this publication will remain unchanged until the stability date indicated on the IEC web site under “http:/webstore.iec.ch“ in the data related to the specific publication. At this date, the publication will be reconfirmed, withdrawn, re
36、placed by a revised edition, or amended. 60904-5 IEC:2011 5 INTRODUCTION When temperature sensors, such as thermocouples, are used to determine the cell temperature of PV devices under natural or simulated steady-state irradiance, two main problems arise. First, a considerable spread of temperature
37、can be observed over the area of the module. Second, as the solar cells are usually not accessible, sensors are attached to the back of the module and the measured temperature thus is influenced by the thermal conductivity of the encapsulant and back materials. These problems are aggravated when det
38、ermining the equivalent cell temperature for on-site measurements of array performance where all cells have slightly different temperatures and one cannot easily determine the average cell temperature. The equivalent cell temperature (ECT) is the average temperature at the electronic junctions of th
39、e device (cells, modules, arrays of one type of module) which equates to the current operating temperature if the entire device were operating uniformly at this junction temperature. 6 60904-5 IEC:2011 PHOTOVOLTAIC DEVICES Part 5: Determination of the equivalent cell temperature (ECT) of photovoltai
40、c (PV) devices by the open-circuit voltage method 1 Scope and object This part of IEC 60904 describes the preferred method for determining the equivalent cell temperature (ECT) of PV devices (cells, modules and arrays of one type of module), for the purposes of comparing their thermal characteristic
41、s, determining NOCT (nominal operating cell temperature) and translating measured I-V characteristics to other temperatures. This standard applies to linear devices with logarithmic V OCdependence on irradiance and in stable conditions. It may be used for all technologies but one has to verify that
42、there is no preconditioning effect influencing the measurement. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced documen
43、t (including any amendments) applies. IEC 60891, Photovoltaic devices Procedures for temperature and irradiance corrections to measured I-V characteristics IEC 60904-1, Photovoltaic devices Part 1: Measurement of photovoltaic current-voltage characteristics IEC 60904-2, Photovoltaic devices Part 2:
44、Requirements for reference solar devices IEC 60904-7, Photovoltaic devices Part 7: Computation of the spectral mismatch correction for measurements of photovoltaic devices IEC 60904-10, Photovoltaic devices Part 10: Methods of linearity measurement IEC 61215, Crystalline silicon terrestrial photovol
45、taic (PV) modules Design qualification and type approval IEC 61829, Crystalline silicon photovoltaic (PV) array On-site measurement of I-V characteristics ISO/IEC 17025, General requirements for competence of testing and calibration laboratories 3 Measurement principle and requirements 3.1 Principle
46、 The method described below is based on the fact that the open-circuit voltage (V OC ) of a solar cell changes with temperature in a predictable fashion. If the open-circuit voltage of the device at standard test conditions is known, together with its temperature coefficient, the 60904-5 IEC:2011 7
47、equivalent temperature of all the cells in the device can be determined. The open-circuit voltage is also slightly affected by the irradiance, so an additional correction may be required as outlined in IEC 60891. Experience shows that the equivalent cell temperature can be determined more precisely
48、by the method described here than by any alternative technique. However, as the temperature coefficient drops rapidly at irradiances below 200 W/m 2 , this method should only be used at irradiances above this threshold. 3.2 General measurement requirements a) The device under test needs to match the
49、 following criteria: 1) The variation of V OCneeds to be linear as defined in IEC 60904-10 with respect to temperature. 2) The variation of V OCneeds to follow a logarithmic dependence with irradiance. 3) It needs to have an ohmic series resistance as otherwise there will be different ECT- coefficients for different temperature regions. 4) The shunt resistances of the device need to be reasonably hig
