1、BSI Standards PublicationPower losses in voltage sourced converter (VSC) valves for high voltage direct current (HVDC) systemsPart 2: Modular multilevel convertersBS EN 62751-2:2014National forewordThis British Standard is the UK implementation of EN 62751-2:2014. It isidentical to IEC 62751-2:2014.
2、The UK participation in its preparation was entrusted to TechnicalCommittee PEL/22, Power electronics.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisions ofa contract. Users are res
3、ponsible for its correct application. The British Standards Institution 2014.Published by BSI Standards Limited 2014ISBN 978 0 580 76760 9ICS 29.200; 29.240Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theSt
4、andards Policy and Strategy Committee on 30 November 2014. Amendments/corrigenda issued since publicationDate Text affectedBRITISH STANDARDBS EN 62751-2:2014EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 62751-2 October 2014 ICS 29.200; 29.240 English Version Power losses in voltage sourced conve
5、rter (VSC) valves for high-voltage direct current (HVDC) systems - Part 2: Modularmultilevel converters (IEC 62751-2:2014) Pertes de puissance dans les valves convertisseur desource de tension (VSC) des systmes en courant continu haute tension (CCHT) - Partie 2: Convertisseursmultiniveaux modulaires
6、 (CEI 62751-2:2014) Bestimmung der Leistungsverluste inSpannungszwischenkreis-Stromrichtern (VSC) frHochspannungsgleichstrom(HG)-Systeme - Teil 2: Modulare Mehrstufen-Stromrichter (IEC 62751-2:2014) This European Standard was approved by CENELEC on 2014-10-01. CENELEC members are bound to comply wit
7、h 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 Manag
8、ement 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
9、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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, L
10、ithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland,Turkey and the United Kingdom. European Committee for Electrotechnical Standardization Comit Europen de Normalisation ElectrotechniqueEuropisches Komitee fr Elektrotechnisc
11、he Normung CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2014 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members. Ref. No. EN 62751-2:2014 E EN 62751-2:2014 - 2 - Foreword The text of document 22F/303/CDV, future edition 1 of IEC
12、 62751-2, prepared by SC 22F “Power electronics for electrical transmission and distribution systems“, of IEC/TC 22 “Power electronic systems and equipment“ was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as EN 62751-2:2014. The following dates are fixed: latest date by which
13、the document has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2015-07-01 latest date by which the national standards conflicting with the document have to be withdrawn (dow) 2017-10-01 Attention is drawn to the possibility that some of
14、the elements of this document may be the subject of patent rights. CENELEC and/or CEN shall not be held responsible for identifying any or all such patent rights. Endorsement notice The text of the International Standard IEC 62751-2:2014 was approved by CENELEC as a European Standard without any mod
15、ification. In the official version, for Bibliography, the following note has to be added for the standard indicated: IEC 61803:1999 NOTE Harmonised as EN 61803:1999. BS EN 62751-2:2014- 3 - EN 62751-2:2014 Annex ZA (normative) Normative references to international publications with their correspondi
16、ng European publications 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. For undated references, the latest edition of the referenced document (including any ame
17、ndments) applies. NOTE 1 When 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 Yea
18、r Title EN/HD Year IEC 60633 - Terminology for high-voltage direct current (HVDC) transmission EN 60633 - IEC 62747 - Terminology for voltage-sourced converters (VSC) for high-voltage direct current (HVDC) systems EN 62747 - IEC 62751-1 2014 Determination of power losses in voltage sourced converter
19、 (VSC) valves for high-voltage direct current (HVDC) systems - Part 1: General requirements EN 62751-1 2014 ISO/IEC Guide 98-3 - Uncertainty of measurement - Part-3: Guide to the expression of uncertainty in measurement (GUM:1995) - - BS EN 62751-2:2014 2 IEC 62751-2:2014 IEC 2014 CONTENTS 1 Scope 7
20、 2 Normative references 7 3 Terms, definitions, symbols and abbreviated terms 7 3.1 Terms and definitions 8 3.2 Symbols and abbreviated terms 9 3.2.1 Valve and simulation data 9 3.2.2 Semiconductor device characteristics 10 3.2.3 Other component characteristics 10 3.2.4 Operating parameters 10 3.2.5
21、 Loss parameters 11 4 General conditions. 11 4.1 General . 11 4.2 Principles for loss determination . 12 4.3 Categories of valve losses 12 4.4 Loss calculation method 13 4.5 Input parameters . 13 4.5.1 General . 13 4.5.2 Input data for numerical simulations 13 4.5.3 Input data coming from numerical
22、simulations . 14 4.5.4 Converter station data . 14 4.5.5 Operating conditions 15 5 Conduction losses . 15 5.1 General . 15 5.2 IGBT conduction losses 16 5.3 Diode conduction losses . 17 5.4 Other conduction losses 18 6 DC voltage-dependent losses 19 7 Losses in d.c. capacitors of the valve 19 8 Swit
23、ching losses 20 8.1 General . 20 8.2 IGBT switching losses . 20 8.3 Diode switching losses 21 9 Other losses 21 9.1 Snubber circuit losses . 21 9.2 Valve electronics power consumption 22 9.2.1 General . 22 9.2.2 Power supply from off-state voltage across each IGBT 23 9.2.3 Power supply from the d.c.
24、 capacitor . 23 10 Total valve losses per HVDC substation 24 Annex A (informative) Description of power loss mechanisms in MMC valves 26 A.1 Introduction to MMC Converter topology . 26 A.2 Valve voltage and current stresses . 29 A.2.1 Simplified analysis with voltage and current in phase . 29 A.2.2
25、Generalised analysis with voltage and current out of phase . 30 BS EN 62751-2:2014IEC 62751-2:2014 IEC 2014 3 A.2.3 Effects of third harmonic injection 31 A.3 Conduction losses in MMC building blocks 32 A.3.1 Description of conduction paths . 32 A.3.2 Conduction losses in semiconductors 38 A.3.3 MMC
26、 building block d.c. capacitor losses . 42 A.3.4 Other conduction losses 42 A.4 Switching losses . 42 A.4.1 Description of state changes 42 A.4.2 Analysis of state changes during cycle 44 A.4.3 Worked example of switching losses 44 A.5 Other losses . 47 A.5.1 Snubber losses 47 A.5.2 DC voltage-depen
27、dent losses 47 A.5.3 Valve electronics power consumption 50 A.6 Application to other variants of valve. 52 A.6.1 General . 52 A.6.2 Two-level full-bridge MMC building block . 52 A.6.3 Multi-level MMC building blocks . 53 Bibliography 55 Figure 1 Two basic versions of MMC building block designs 15 Fi
28、gure 2 Conduction paths in MMC building blocks 16 Figure A.1 Phase unit of the modular multi-level converter (MMC) in basic half-bridge, two-level arrangement, with submodules . 27 Figure A.2 Phase unit of the cascaded two-level converter (CTL) in half-bridge form . 28 Figure A.3 Basic operation of
29、the MMC converters . 29 Figure A.4 MMC converters showing composition of valve current . 30 Figure A.5 Phasor diagram showing a.c. system voltage, converter a.c. voltage and converter a.c. current 31 Figure A.6 Effect of 3rdharmonic injection on converter voltage and current . 32 Figure A.7 Two func
30、tionally equivalent variants of a “half-bridge”, two-level MMC building block 33 Figure A.8 Conducting states in “half-bridge”, two-level MMC building block 34 Figure A.9 Typical patterns of conduction for inverter operation (left) and rectifier operation (right) 35 Figure A.10 Example of converter
31、with only one MMC building block per valve to illustrate switching behaviour 36 Figure A.11 Inverter operation example of switching events . 36 Figure A.12 Rectifier operation example of switching events 37 Figure A.13 Valve current and mean rectified valve current 39 Figure A.14 IGBT and diode swit
32、ching energy as a function of collector current . 43 Figure A.15 Valve voltage, current and switching behaviour for a hypothetical MMC valve consisting of 5 submodules 45 Figure A.16 Power supply from IGBT terminals 50 Figure A.17 Power supply from IGBT terminals in cell 51 Figure A.18 Power supply
33、from d.c. capacitor in submodule . 52 Figure A.19 One “full-bridge”, two-level MMC building block 52 BS EN 62751-2:2014 4 IEC 62751-2:2014 IEC 2014 Figure A.20 Four possible variants of three-level MMC building block 54 Table 1 Contributions to valve losses in different operating modes 25 Table A.1
34、Hard switching events 42 Table A.2 Soft switching events . 44 Table A.3 Summary of switching events from Figure A.15 46 BS EN 62751-2:2014IEC 62751-2:2014 IEC 2014 7 POWER LOSSES IN VOLTAGE SOURCED CONVERTER (VSC) VALVES FOR HIGH-VOLTAGE DIRECT CURRENT (HVDC) SYSTEMS Part 2: Modular multilevel conve
35、rters 1 Scope This part of IEC 62751 gives the detailed method to be adopted for calculating the power losses in the valves for an HVDC system based on the “modular multi-level converter”, where each valve in the converter consists of a number of self-contained, two-terminal controllable voltage sou
36、rces connected in series. It is applicable both for the cases where each modular cell uses only a single turn-off semiconductor device in each switch position, and the case where each switch position consists of a number of turn-off semiconductor devices in series (topology also referred to as “casc
37、aded two-level converter”). The main formulae are given for the two-level “half-bridge” configuration but guidance is also given in Annex A as to how to extend the results to certain other types of MMC building block configuration. The standard is written mainly for insulated gate bipolar transistor
38、s (IGBTs) but may also be used for guidance in the event that other types of turn-off semiconductor devices are used. Power losses in other items of equipment in the HVDC station, apart from the converter valves, are excluded from the scope of this standard. This standard does not apply to converter
39、 valves for line-commutated converter HVDC systems. 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. For undated references, the latest edi
40、tion of the referenced document (including any amendments) applies. IEC 60633, Terminology for high-voltage direct-current (HVDC) transmission IEC 62747, Terminology for voltage-sourced converters (VSC) for high-voltage direct current (HVDC) systems IEC 62751-1:2014, Power losses in voltage sourced
41、converter (VSC) valves for high-voltage direct current (HVDC) systems Part 1: General requirements ISO/IEC Guide 98-3, Uncertainty of measurement Part 3: Guide to the expression of uncertainty in measurement (GUM:1995) 3 Terms, definitions, symbols and abbreviated terms For the purposes of this docu
42、ment, the terms and definitions given in IEC 60633, IEC 62747, IEC 62751-1, as well as the following apply. BS EN 62751-2:2014 8 IEC 62751-2:2014 IEC 2014 3.1 Terms and definitions 3.1.1 modular multi-level converter MMC multi-level converter in which each VSC valve consists of a number of MMC build
43、ing blocks connected in series Note 1 to entry: This note applies to the French language only. 3.1.2 MMC building block self-contained, two-terminal controllable voltage source together with d.c. capacitor(s) and immediate auxiliaries, forming part of a MMC 3.1.3 IGBT-diode pair arrangement of IGBT
44、and free-wheeling diode connected in inverse parallel 3.1.4 switch position semiconductor function which behaves as a single, indivisible switch Note 1 to entry: A switch position may consist of a single IGBT-diode pair or, in the case of the cascaded two level converter, a series connection of mult
45、iple IGBT-diode pairs. 3.1.5 cascaded two-level converter CTL modular multi-level converter in which each switch position consists of more than one IGBT-diode pair connected in series Note 1 to entry: This note applies to the French language only. 3.1.6 submodule MMC building block where each switch
46、 position consists of only one IGBT-diode pair 3.1.7 cell MMC building block where each switch position consists of more than one IGBT-diode pair connected in series 3.1.8 turn-off semiconductor device controllable semiconductor device which may be turned on and off by a control signal, for example
47、an IGBT 3.1.9 insulated gate bipolar transistor IGBT turn-off semiconductor device with three terminals: a gate terminal (G) and two load terminals emitter (E) and collector (C) Note 1 to entry: This note applies to the French language only. 3.1.10 operating state condition in which the HVDC substat
48、ion is energized and the converters are de-blocked BS EN 62751-2:2014IEC 62751-2:2014 IEC 2014 9 Note 1 to entry: Unlike line-commutated converter, VSC can operate with zero active/reactive power output. 3.1.11 no-load operating state condition in which the HVDC substation is energized but the IGBTs
49、 are blocked and all necessary substation service loads and auxiliary equipment are connected 3.1.12 idling operating state condition in which the HVDC substation is energized and the IGBTs are de-blocked but with no active or reactive power output at the point of common connection to the a.c. network Note 1 to entry: The “idling operating” and “no-load” conditions are similar but from the no-load state, several seconds may be needed before power can be transmitte
