1、BSI Standards Publication Utility-interconnected photovoltaic inverters Test procedure for low voltage ride-through measurements PD IEC/TS 62910:2015National foreword This Published Document is the UK implementation of IEC/TS 62910:2015. The UK participation in its preparation was entrusted to Techn
2、ical Committee GEL/82, Photovoltaic Energy Systems. A list of organizations represented on this committee can be obtained on request to its secretary. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The Briti
3、sh Standards Institution 2015. Published by BSI Standards Limited 2015 ISBN 978 0 580 85990 8 ICS 27.160 Compliance with a British Standard cannot confer immunity from legal obligations. This Published Document was published under the authority of the Standards Policy and Strategy Committee on 30 No
4、vember 2015. Amendments/corrigenda issued since publication Date Text affected PUBLISHED DOCUMENT PD IEC/TS 62910:2015 IEC TS 62910 Edition 1.0 2015-10 TECHNICAL SPECIFICATION Utility-interconnected photovoltaic inverters Test procedure for low voltage ride-through measurements INTERNATIONAL ELECTRO
5、TECHNICAL COMMISSION ICS 27.160 ISBN 978-2-8322-2957-6 Registered trademark of the International Electrotechnical Commission Warning! Make sure that you obtained this publication from an authorized distributor. colour inside PD IEC/TS 62910:2015 2 IEC TS 62910:2015 IEC 2015 CONTENTS FOREWORD . 4 1 S
6、cope 6 2 Normative references 6 3 Terms, definitions, symbols and abbreviations . 6 3.1 Terms, definitions and symbols . 6 3.2 Abbreviations 8 4 Test circuit and equipment . 9 4.1 General . 9 4.2 Test circuit 9 4.3 Test equipment . 9 4.3.1 Measuring instruments. 9 4.3.2 DC source . 10 4.3.3 Short-ci
7、rcuit emulator 10 4.3.4 Converter based grid simulator 13 5 Test . 13 5.1 Test protocol . 13 5.2 Test curve . 15 5.3 Test procedure 16 5.3.1 Pre-test . 16 5.3.2 No-load test . 16 5.3.3 Tolerance 16 5.3.4 Load test . 17 6 Assessment criteria . 17 Annex A (informative) Circuit faults and voltage drops
8、 . 18 A.1 Fault types 18 A.2 Voltage drops . 20 A.2.1 General . 20 A.2.2 Three-phase short-circuit fault . 20 A.2.3 Two-phase short-circuit fault with ground . 21 A.2.4 Two-phase short-circuit fault without ground 22 A.2.5 Single-phase short-circuit fault with ground . 23 Annex B (informative) Deter
9、mination of critical performance values in LVRT testing 24 B.1 General . 24 B.2 Drop depth ratio 24 B.3 Ride-through time . 24 B.4 Reactive current 24 B.5 Active power . 25 Bibliography 26 Figure 1 Testing circuit diagram . 9 Figure 2 Short-circuit emulator . 11 Figure 3 Converter device example 13
10、Figure 4 LVRT curve example 16 Figure 5 Tolerance of voltage drop. 17 PD IEC/TS 62910:2015IEC TS 62910:2015 IEC 2015 3 Figure A.1 Grid fault diagram . 20 Figure A.2 Diagram of voltage vector for three-phase short-circuit fault . 20 Figure A.3 Diagram of voltage vector of two-phase (BC) short-circuit
11、 fault with ground 21 Figure A.4 Diagram of voltage vector of two-phase (BC) short-circuit fault . 22 Figure A.5 Diagram of voltage vector of single-phase (A) short-circuit fault with ground 23 Figure B.1 Determination of reactive current output . 25 Figure B.2 Determination of active power recovery
12、 25 Table 1 Accuracy of measurements . 10 Table 2 Fault type and switch status 12 Table 3 Test specification for LVRT (indicative) . 14 Table A.1 Short-circuit paths for different fault types 18 Table A.2 Amplitude and phase changes in three-phase short-circuit fault . 21 Table A.3 Amplitude and pha
13、se changes in two-phase (BC) short-circuit fault with ground 22 Table A.4 Amplitude and phase changes in two-phase (BC) short-circuit fault 22 Table A.5 Amplitude and phase changes in single-phase (A) short-circuit fault with ground 23 PD IEC/TS 62910:2015 4 IEC TS 62910:2015 IEC 2015 INTERNATIONAL
14、ELECTROTECHNICAL COMMISSION _ UTILITY-INTERCONNECTED PHOTOVOLTAIC INVERTERS TEST PROCEDURE FOR LOW VOLTAGE RIDE-THROUGH MEASUREMENTS FOREWORD 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising all national electrotechnical committees (IE
15、C National Committees). The object of IEC is to promote international co-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,
16、 Publicly Available Specifications (PAS) and Guides (hereafter referred 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-
17、governmental organizations liaising with the IEC also participate in this 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
18、IEC on technical matters express, as nearly as possible, an international 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 ac
19、cepted by IEC National Committees in that sense. While all reasonable efforts 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 internat
20、ional uniformity, IEC National Committees undertake to apply IEC Publications 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
21、latter. 5) IEC itself does not provide any attestation of conformity. Independent 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 s
22、hould ensure that they have the latest edition of this publication. 7) No 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 d
23、amage of any nature whatsoever, whether direct or indirect, or for costs (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
24、of the referenced publications is indispensable for the correct application 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 ri
25、ghts. The main task of IEC technical committees is to prepare International Standards. In exceptional circumstances, a technical committee may propose the publication of a technical specification when the required support cannot be obtained for the publication of an International Standard, despite r
26、epeated efforts, or the subject is still under technical development or where, for any other reason, there is the future but no immediate possibility of an agreement on an International Standard. Technical specifications are subject to review within three years of publication to decide whether they
27、can be transformed into International Standards. IEC TS 62910, which is a technical specification, has been prepared by IEC technical committee 82: Solar photovoltaic energy systems. PD IEC/TS 62910:2015IEC TS 62910:2015 IEC 2015 5 The text of this technical specification is based on the following d
28、ocuments: Enquiry draft Report on voting 82/884/DTS 82/1005/RVC Full information on the voting for the approval of this technical specification can be found in the report on voting indicated in the above table. This publication has been drafted in accordance with the ISO/IEC Directives, Part 2. The
29、committee has decided that the contents of this publication will remain unchanged until the stability date indicated on the IEC website under “http:/webstore.iec.ch“ in the data related to the specific publication. At this date, the publication will be transformed into an International standard, rec
30、onfirmed, withdrawn, replaced by a revised edition, or amended. A bilingual version of this publication may be issued at a later date. IMPORTANT The colour inside logo on the cover page of this publication indicates that it contains colours which are considered to be useful for the correct understan
31、ding of its contents. Users should therefore print this document using a colour printer. PD IEC/TS 62910:2015 6 IEC TS 62910:2015 IEC 2015 UTILITY-INTERCONNECTED PHOTOVOLTAIC INVERTERS TEST PROCEDURE FOR LOW VOLTAGE RIDE-THROUGH MEASUREMENTS 1 Scope This Technical Specification provides a test proce
32、dure for evaluating the performance of Low Voltage Ride-Through (LVRT) functions in inverters used in utility-interconnected PV systems. The technical specification is most applicable to large systems where PV inverters are connected to utility HV distribution systems. However, the applicable proced
33、ures may also be used for LV installations in locations where evolving LVRT requirements include such installations, e.g. single-phase or 3-phase systems. The assessed LVRT performance is valid only for the specific configuration and operational mode of the inverter under test. Separate assessment i
34、s required for the inverter in other factory or user-settable configurations, as these may cause the inverter LVRT response to behave differently. The measurement procedures are designed to be as non-site-specific as possible, so that LVRT characteristics measured at one test site, for example, can
35、also be considered valid at other sites. This technical specification is for testing of PV inverters, though it contains information that may also be useful for testing of a complete PV power plant consisting of multiple inverters connected at a single point to the utility grid. It further provides
36、a basis for utility- interconnected PV inverter numerical simulation and model validation. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies.
37、 For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 61400-21:2008, Wind turbines Part 21: Measurement and assessment of power quality characteristics of grid connected wind turbines 3 Terms, definitions, symbols and abbreviations 3.1 Terms,
38、definitions and symbols For the purposes of this document, the following terms, definitions and symbols apply. 3.1.1 drop depth magnitude of voltage drop during a fault or simulated fault, as a percentage of the nominal supply voltage 3.1.2 double drop sudden decline of the nominal voltage to a valu
39、e below 90 % of the voltage of PCC, followed after a short time by a voltage recovery, which happened twice. Voltage changes which do not PD IEC/TS 62910:2015IEC TS 62910:2015 IEC 2015 7 reduce the voltage to below 90 % of the voltage of PCC are not considered to be voltage drops 3.1.3 equipment und
40、er test EUT EUT indicates the equipment on which these tests are performed and refers to the utility- interconnected PV inverter. During test period, EUT is connected with PV simulator instead of real PV modules on the DC side, while AC side is connected with grid 3.1.4 IT system IT power system has
41、 all live parts isolated from earth or one point connected to earth through an impedance. The exposed-conductive-parts of the electrical installation are earthed independently or collectively or to the earthing of the system SOURCE: IEC 60364-1:2005, 312.2.3 3.1.5 I qoutput reactive current of EUT 3
42、.1.6 low voltage ride through LVRT capability of an inverter to continue generating power to connected loads during a limited duration loss or drop of grid voltage 3.1.7 maximum MPP voltage maximum voltage at which the EUT can convert its rated power under MPPT conditions SOURCE: EN 50530:2010 3.1.8
43、 maximum power point tracking MPPT control strategy of operation at maximum power point or nearby 3.1.9 minimum MPP voltage minimum voltage at which the EUT can convert its rated power under MPPT conditions SOURCE: EN 50530:2010 3.1.10 N EUT access point of the EUT during the test 3.1.11 P Nrated po
44、wer of EUT 3.1.12 point of common coupling PCC point of a power supply network, electrically nearest to a particular load, at which other loads are, or may be, connected PD IEC/TS 62910:2015 8 IEC TS 62910:2015 IEC 2015 Note 1 to entry: These loads can be either devices, equipment or system, or dist
45、inct customers installations. Note 2 to entry: In some applications, the term “point of common coupling” is restricted to public networks. SOURCE: IEC 60050-161:1990, 161-07-15 3.1.13 proportionality constant K K-factor voltage support of EUT in accordance with the voltage drops. The K-factor is to
46、be specified by the EUT manufacturer. 3.1.14 PV array simulator simulator that has I-V characteristics equivalent to a PV array 3.1.15 PV simulator MPP voltage U MPP, PVSMPP voltage of the setting PV curve that is provided by the PV simulator 3.1.16 S EUTapparent short-circuit power at N EUT3.1.17 s
47、ingle drop sudden decline of the nominal voltage to a value below 90 % of the voltage of PCC, followed after a short time by a voltage recovery, which happened once. Voltage changes which do not reduce the voltage to below 90 % of the voltage of PCC are not considered to be voltage drops 3.1.18 Z gr
48、idgrid short-circuit impedance value of the MP1 (see Figure 1) 3.1.19 Z i impedance value between the fault point and PCC 3.1.20 Z pimpedance value between the fault point and EUT 3.2 Abbreviations AC alternating current A/D analog to digital DC direct current HV high voltage LV low voltage MV middl
49、e voltage RMS root mean square PD IEC/TS 62910:2015IEC TS 62910:2015 IEC 2015 9 4 Test circuit and equipment 4.1 General The circuits and equipment described in this clause are developed to allow tests that simulate the full range of anticipated grid faults, including: Single phase to ground fault (any phase). Two phase isolated fault, between any two phases. Two phase grounded fault, involving any two phases. Three phase short-circuit faul
