prEN IEC 60700-3:2021

Thyristor valves for high voltage direct current (HVDC) power transmission - Part 3: Essential ratings (limiting values) and characteristics

This part of IEC 60700 specifies the service conditions, the definitions of essential ratings and characteristics of thyristor valves utilized in line commutated converters with three-phase bridge connections to realize the conversion from AC to DC and vice versa for high voltage direct current (HVDC) power transmission applications. It is applicable for air insulated, liquid cooled and indoor thyristor valves.

Thyristorventile für Hochspannungsgleichstrom - Energieübertragung (HGÜ) – Teil 3: Wesentliche Nenngrößen (begrenzende Werte) und Eigenschaften

Valves à thyristors pour le transport d’énergie en courant continu à haute tension (CCHT) - Partie 3: Valeurs assignées (valeurs limites) et caractéristiques essentielles

Tiristorski ventili (elektronke) za visokonapetostni enosmerni prenos (HVDC) električne energije - 3. del: Bistvene lastnosti (mejne vrednosti) in karakteristike

General Information

• Status: Not Published
• ICS: 29.200 - Rectifiers. Convertors. Stabilized power supply
• Technical Committee: CLC/TC 22X - Power electronics
• Drafting Committee: IEC/SC 22F - IEC_SC_22F
• Current Stage: 4020 - Enquiry circulated
• Due Date: 17-Dec-2021
• Completion Date: 17-Dec-2021
• Ref Project: oSIST prEN IEC 60700-3:2022 - Thyristor valves for high voltage direct current (HVDC) power transmission - Part 3: Essential ratings (limiting values) and characteristics

Standards Content (sample)

SLOVENSKI STANDARD
oSIST prEN IEC 60700-3:2022
01-februar-2022
Tiristorski ventili (elektronke) za visokonapetostni enosmerni prenos (HVDC)

električne energije - 3. del: Bistvene lastnosti (mejne vrednosti) in karakteristike

Thyristor valves for high voltage direct current (HVDC) power transmission - Part 3:

Essential ratings (limiting values) and characteristics

Valves à thyristors pour le transport d’énergie en courant continu à haute tension

(CCHT) - Partie 3: Valeurs assignées (valeurs limites) et caractéristiques essentielles

Ta slovenski standard je istoveten z: prEN IEC 60700-3:2021
ICS:
29.200 Usmerniki. Pretvorniki. Rectifiers. Convertors.
Stabilizirano električno Stabilized power supply
napajanje
31.080.20 Tiristorji Thyristors
oSIST prEN IEC 60700-3:2022 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN IEC 60700-3:2022
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oSIST prEN IEC 60700-3:2022
22F/667/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 60700-3 ED1
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2021-12-17 2022-03-11
SUPERSEDES DOCUMENTS:
22F/640/CD, 22F/659/CC
IEC SC 22F
SECRETARIAT: SECRETARY:
Russian Federation Mr. Lev TRAVIN
OF INTEREST TO THE FOLLOWING COMMITTEES: PROPOSED HORIZONTAL STANDARD:
TC 115
Other TC/SCs are requested to indicate their interest, if any, in this
CDV to the secretary.
FUNCTIONS CONCERNED:
EMC ENVIRONMENT QUALITY ASSURANCE SAFETY

SUBMITTED FOR CENELEC PARALLEL VOTING NOT SUBMITTED FOR CENELEC PARALLEL VOTING

Attention IEC-CENELEC parallel voting
The attention of IEC National Committees, members of CENELEC,
is drawn to the fact that this Committee Draft for Vote (CDV) is
submitted for parallel voting.
The CENELEC members are invited to vote through the CENELEC
online voting system.

This document is still under study and subject to change. It should not be used for reference purposes.

Recipients of this document are invited to submit, with their comments, notification of any relevant patent rights of which they are aware

and to provide supporting documentation.
TITLE:

Thyristor valves for high voltage direct current (HVDC) power transmission - Part 3: Essential ratings (limiting

values) and characteristics
PROPOSED STABILITY DATE: 2027
NOTE FROM TC/SC OFFICERS:

As the plenary meeting of SC 22F was cancelled in 2020 due to COVID-19 pandemic (see 22F/591/INF),

comments of National Committees on 22F/590/CD containing in document 22F/605/CC were considered by

SC 22F Chair, secretary, convenor and members of SC 22F/WG 35.

The agreed decision supported by the National Committee of Sweden has been taken that SC 22F/WG 35 is

to develop the current second CD by July 2021. The second CD (22F/640/CD) was prepared by SC 22F/WG

35 (convenor Mr. Yantao LOU, CN).

Compilation of comments 22F/659/CC on document 22F/640/CD was considered by the secretary of SC 22F,

the Chair of SC 22F, Convenor and members of SC22F/WG35. The Chair of SC 22F made decision

(supported by the secretary of SC 22F) to prepare a CDV by putting agreed changes into 22F/640/CD by

2021-12

Copyright © 2021 International Electrotechnical Commission, IEC. All rights reserved. It is permitted to download this

electronic file, to make a copy and to print out the content for the sole purpose of preparing National Committee positions.

You may not copy or "mirror" the file or printed version of theocument, or any part of it, for any other purpose without

permission in writing from IEC.
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1 CONTENTS

2 Page

3 Foreword ............................................................................................................................ - 7 -

4 1 Scope .......................................................................................................................... - 7 -

5 2 Normative references ................................................................................................... - 7 -

6 3 Symbols and abbreviations .......................................................................................... - 7 -

7 3.1 Subscripts ........................................................................................................... - 7 -

8 3.2 Letter symbols .................................................................................................... - 8 -

9 3.3 Abbreviations ...................................................................................................... - 9 -

10 4 Service conditions ........................................................................................................ - 9 -

11 4.1 General ............................................................................................................... - 9 -

12 4.2 Environmental conditions .................................................................................... - 9 -

13 4.2.1 Site altitude ............................................................................................. - 9 -

14 4.2.2 Air temperature and humidity range in valve halls ................................... - 9 -

15 4.2.3 Cleanness in valve halls .......................................................................... - 9 -

16 4.2.4 Seismic conditions .................................................................................. - 9 -

17 4.3 System conditions ............................................................................................... - 9 -

18 4.3.1 General information of the system ........................................................... - 9 -

19 4.3.2 AC system voltage ................................................................................ - 10 -

20 4.3.3 AC system frequency ............................................................................ - 10 -

21 4.3.4 DC system voltage ................................................................................ - 10 -

22 4.3.5 DC system current and overload requirements ...................................... - 10 -

23 4.3.6 Short circuit current requirements for thyristor valves ............................ - 10 -

24 4.3.7 Insulation coordination design related to thyristor valves ....................... - 10 -

25 4.4 Technical parameters for 6-pulse bridge design ................................................ - 11 -

26 4.4.1 General ................................................................................................. - 11 -

27 4.4.2 Voltage parameters ............................................................................... - 11 -

28 4.4.3 Current parameters ............................................................................... - 11 -

29 4.4.4 Valve arrester parameters ..................................................................... - 12 -

30 4.4.5 Other system parameters ...................................................................... - 12 -

31 4.5 Other conditions................................................................................................ - 13 -

32 5 Ratings ...................................................................................................................... - 13 -

33 5.1 Voltage and current ratings (limiting values) ..................................................... - 13 -

34 5.1.1 Rated AC voltage across valve (U ) .................................................... - 13 -

v0N

35 5.1.2 Maximum steady state AC voltage across valve (Uv0max) ....................... - 13 -

36 5.1.3 Maximum temporary state AC voltage across valve (U ) ................. - 13 -

v0maxT

37 5.1.4 Minimum temporary state AC voltage across valve (Uv0minT) .................. - 13 -

38 5.1.5 Valve repetitive peak off-state voltage (U ) ...................................... - 13 -

vDRM

39 5.1.6 Valve non-repetitive peak off-state voltage (UvDSM) ................................ - 13 -

40 5.1.7 Valve repetitive peak reverse voltage (U ) ........................................ - 14 -

vRRM

41 5.1.8 Valve non-repetitive peak reverse voltage (UvRSM) ................................. - 14 -

42 5.1.9 Valve switching impulse withstand voltage (SIWV ) .............................. - 14 -

43 5.1.10 Valve lightning impulse withstand voltage (LIWVV) ................................ - 14 -

44 5.1.11 Valve steep-front impulse withstand voltage (STIWV ) .......................... - 14 -

45 5.1.12 Valve switching impulse protective firing voltage (SIPLPF) ..................... - 14 -

46 5.1.13 Valve RMS current (Iv(rms)) ..................................................................... - 14 -

47 5.1.14 Valve average current (Iv(av)) ................................................................. - 14 -

48 5.1.15 Valve one-loop fault current with re-applied forward voltage (I ) ......... - 14 -

SCα

49 5.1.16 Valve multiple-loop fault current without re-applied forward voltage (ISCβ)- 15 -

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50 5.2 Delay and extinction angle ratings (limiting values) ........................................... - 15 -

51 5.2.1 Rated firing delay angle (α ) ................................................................. - 15 -

52 5.2.2 Minimum allowable firing delay angle (αmin) ........................................... - 15 -

53 5.2.3 Maximum allowable firing delay angle (α ) ......................................... - 15 -

max

54 5.2.4 Minimum temporary state firing delay angle (αminT) ................................ - 15 -

55 5.2.5 Rated extinction angle (γ ) .................................................................... - 15 -

56 5.2.6 Minimum allowable extinction angle (γmin) ............................................. - 15 -

57 5.2.7 Maximum allowable extinction angle (γ ) ............................................ - 15 -

max

58 5.2.8 Minimum temporary state extinction angle (γminT) .................................. - 15 -

59 5.3 Insulation and test voltage levels (limiting values) ............................................. - 15 -

60 5.3.1 Maximum DC voltage between valve terminals (Ud(v)max)........................ - 15 -

61 5.3.2 Maximum DC voltage across multiple valve unit (U ) ..................... - 16 -

d(m)max

62 5.3.3 Maximum DC voltage across valve support (Ud(vs)max) ............................ - 16 -

63 5.3.4 Maximum AC voltage between valve terminals (U ) ....................... - 16 -

ac(v)max

64 5.3.5 Maximum AC voltage across multiple valve unit (Uac(m)max) .................... - 16 -

65 5.3.6 Maximum AC voltage across valve support (U ) ........................... - 16 -

ac(vs)max

66 5.3.7 Maximum switching impulse voltage between valve terminals (Us(v)max) . - 17 -

67 5.3.8 Maximum switching impulse voltage across multiple valve unit (U )- 17 -
s(m)max

68 5.3.9 Maximum switching impulse voltage across valve support (Us(vs)max) ..... - 17 -

69 5.3.10 Maximum lightning impulse voltage between valve terminals (U ) ... - 17 -

l(v)max

70 5.3.11 Maximum lightning impulse voltage across multiple valve unit (Ul(m)max). - 17 -

71 5.3.12 Maximum lightning impulse voltage across valve support (U ) ....... - 17 -

l(vs)max

72 5.3.13 Maximum steep-front impulse voltage between valve terminals (Ust(v)max)- 18 -

73 5.3.14 Maximum steep-front impulse voltage across multiple valve unit (Ust(m)max)- 18

74 -

75 5.3.15 Maximum steep-front impulse voltage across valve support (U ) .. - 18 -

st(vs)max

76 6 Characteristics ........................................................................................................... - 18 -

77 6.1 General ............................................................................................................. - 18 -

78 6.2 Losses characteristics ....................................................................................... - 18 -

79 6.2.1 General ................................................................................................. - 18 -

80 6.2.2 Maximum load loss per valve at rated condition (Pv0max) ........................ - 19 -

81 6.2.3 Maximum no-load loss per valve (P ) ............................................... - 19 -

v0max

82 6.2.4 Maximum heat emission to valve hall (PEmax) ......................................... - 19 -

83 6.3 Protection characteristics .................................................................................. - 19 -

84 6.3.1 Valve lightning impulse protective firing voltage (LIPLPF) ....................... - 19 -

85 6.3.2 Valve steep-front impulse protective firing voltage (STIPL ) ................. - 19 -

86 6.3.3 Thyristor protective firing level (VPF) ...................................................... - 19 -

87 6.3.4 Thyristor forward recovery protection level (V ) ................................... - 19 -

88 6.3.5 Thyristor forward du/dt protection level (du/dtPF) ................................... - 19 -

89 6.3.6 Valve protective firing trip level (N ) ................................................. - 19 -

tripPF

90 6.3.7 Valve loss of redundancy trip level (Ntrip) ............................................... - 20 -

91 6.4 Temperature characteristics .............................................................................. - 20 -

92 6.4.1 Maximum cooling medium temperature at valve inlet (T(in)max) ............... - 20 -

93 6.4.2 Maximum cooling medium temperature at valve outlet (T ) ............ - 20 -

(out)max

94 6.4.3 Thyristor junction temperature at rated condition (TjN) ........................... - 20 -

95 6.4.4 Maximum thyristor junction temperature (Tjmax) ...................................... - 20 -

96 6.4.5 Storage temperature (Tstg) ..................................................................... - 20 -

97 6.5 Reliability characteristics .................................................................................. - 20 -

98 6.5.1 General ................................................................................................. - 20 -

99 6.5.2 Expected annual failure rate of thyristor level (λ ) ................................. - 20 -

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100 6.6 Other characteristics ......................................................................................... - 21 -

101 6.6.1 Valve on-state voltage (U ) ............................................................... - 21 -

v(on)

102 6.6.2 Maximum steady state operating time at α=90° (t90max) .......................... - 21 -

103 6.6.3 Maximum temporary state operating time at α=90° (t ) ................... - 21 -

90maxT

104 6.6.4 Maximum steady state commutation overshoot factor (kc) ..................... - 21 -

105 6.6.5 Maximum temporary state commutation overshoot factor (k ) ............... - 21 -

106 Figure 1- Typical arrester arrangement for converter units with two 12-pulse bridges in

107 series ................................................................................................................ - 22 -

108 Figure 2-- Operating voltage of valve and valve arrester in rectified mode ........................ - 23 -

109 Figure 3 - Thyristor valve voltage waveforms in different operation modes ....................... - 23 -

110 Figure 4-One loop valve short circuit current and voltage waveforms ................................ - 24 -

111 Figure 5 - Multiple loop valve short circuit current and voltage waveforms ........................ - 24 -

112 Figure 6 - Continuous operating voltages at various locations for a 12-pulse bridge in rectifier

113 mode ......................................................................................................................... - 25 -

114 Annex A Input parameters for thyristor valve design ………………………………………….- 26 –

115 Annex B Technical data sheet of thyristor valves ……………………………………………. – 29 –
116 Bibliography …………………………………………………………………………………………. – 33 -
117
118
119
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120 INTERNATIONAL ELECTROTECHNICAL COMMISSION
121
122 ____________
123
124 THYRISTOR VALVES FOR HIGH VOLTAGE DIRECT CURRENT (HVDC) POWER
125 TRANSMISSION –
126
127 Part 3: Essential ratings (limiting values) and characteristics
128
129 FOREWORD

130 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising all

131 national electrotechnical committees (IEC National Committees). The object of IEC is to promote international co-

132 operation on all questions concerning standardization in the electrical and electronic fields. To this end and in addition to

133 other activities, IEC publishes International Standards, Technical Specifications, Technical Reports, Publicly Available

134 Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their preparation is entrusted to technical

135 committees; any IEC National Committee interested in the subject dealt with may participate in this preparatory work.

136 International, governmental and non-governmental organizations liaising with the IEC also participate in this preparation.

137 IEC collaborates closely with the International Organization for Standardization (ISO) in accordance with conditions

138 determined by agreement between the two organizations.

139 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international

140 consensus of opinion on the relevant subjects since each technical committee has representation from all interested IEC

141 National Committees.

142 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National Committees in

143 that sense. While all reasonable efforts are made to ensure that the technical content of IEC Publications is accurate, IEC

144 cannot be held responsible for the way in which they are used or for any misinterpretation by any end user.

145 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications transparently to

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148 5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity assessment

149 services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any services carried out by

150 independent certification bodies.

151 6) All users should ensure that they have the latest edition of this publication.

152 7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and members of

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154 nature whatsoever, whether direct or indirect, or for costs (including legal fees) and expenses arising out of the publication,

155 use of, or reliance upon, this IEC Publication or any other IEC Publications.

156 8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is

157 indispensable for the correct application of this publication.

158 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent rights.

159 IEC shall not be held responsible for identifying any or all such patent rights.

160 International Standard IEC 60700-3 ED1 has been prepared by subcommittee 22F: Power electronics

161 for electrical transmission and distribution systems, of IEC technical committee 22: Power electronic

162 systems and equipment.
163 The text of this International Standard is based on the following documents:
FDIS Report on voting
22F/XX/FDIS 22F/XX/RVD
164

165 Full information on the voting for the approval of this International Standard can be found in the report

166 on voting indicated in the above table.

167 This document has been drafted in accordance with the ISO/IEC Directives, Part 2.

168 The committee has decided that the contents of this document will remain unchanged until the stability

169 date indicated on the IEC website under "http://webstore.iec.ch" in the data related to the specific

170 document. At this date, the document will be
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171 • reconfirmed,
172 • withdrawn,
173 • replaced by a revised edition, or
174 • amended.
175
176
177
178
179
180
181
182
183
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184 THYRISTOR VALVES FOR HIGH VOLTAGE DIRECT CURRENT (HVDC)
185 POWER TRANSMISSION –
186 Part 3: Essential ratings (limiting values) and characteristics
187
188 1 Scope

189 This part of IEC 60700 specifies the service conditions, the definitions of essential ratings and

190 characteristics of thyristor valves utilized in line commutated converters with three-phase bridge

191 connections to realize the conversion from AC to DC and vice versa for high voltage direct current

192 (HVDC) power transmission applications. It is applicable for air insulated, liquid cooled and indoor

193 thyristor valves.
194 2 Normative references

195 The following referenced documents are indispensable for the application of this document. For dated

196 references, only the edition cited applies. For undated references, the latest edition of the referenced

197 document (including any amendments) applies.

198 IEC 60060-1, High-voltage test techniques - Part 1: General definitions and test requirements

199 IEC 60071-1, lnsulation co-ordination - Part 1: Definitions, principles and rules

200 IEC 60071-5, lnsulation co-ordination - Part 5: Procedures for high-voltage direct current (HVDC)

201 converter stations

202 IEC 60700-1, Thyristor valves for high voltage direct current (HVDC) power transmission - Part 1:

203 Electrical testing

204 IEC 60700-2, Thyristor valves for high voltage direct current (HVDC) power transmission - Part 2:

205 Terminology

206 IEC TR 60919-1, Performance of high-voltage direct current (HVDC) systems with line-commutated

207 converters - Part 1: Steady-state conditions

208 IEC 61803, Determination of power losses in high-voltage direct current (HVDC) converter stations

209 with line-commutated converters
210 3 Symbols and abbreviations

211 The list covers only the most frequently used symbols and abbreviations related to this document. For

212 a more complete list of symbols and abbreviations refer to the standards listed in the normative

213 references.
214 3.1 Subscripts
215 0 (zero) at no load
216 i ideal
217 N nominal or rated value
218 d direct current or voltage
219 ac alternating current or voltage
220 r resistive or overvoltage
221 x inductive
222 u undervoltage
223 j thyristor junction
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224 v valve or valve side of converter transformer
225 m multiple valve (unit)
226 vs valve support
227 s switching impulse or stray
228 l lightning impulse
229 st steep-front impulse
230 PF protective firing
231 RP recovery protection
232 T temporary
233 S short term
234 SC short circuit
235 max maximum
236 min minimum
237 rms root mean square
238 av average
239 ar arrester
240 DRM off-state repetitive maximum value
241 DSM off-state non-repetitive maximum value
242 RRM reverse repetitive maximum value
243 RSM reverse non-repetitive maximum value
244 3.2 Letter symbols
245 α (trigger/firing) delay angle
246 γ extinction angle
247 μ (commutation) overlap angle

248 Xt commutation circuit reactance, including leakage reactance of converter transformer and other

249 reactance in the commutation circuit which influence commutation process

250 Pcu on-load losses of converter transformer and DC smoothing reactor when a six-pulse bridge is

251 operating at rated load
252 Rth equivalent resistance of the voltage drop of the thyristor valve
253 f rated AC system frequency
254 tp valve conduction interval
255 t valve hold-off interval

256 kdf uneven voltage distribution factor, defined as the maximum deviation of the peak voltages of

257 thyristor levels in a valve under the specified type of impulses, representing the degree of

258 uneven voltage distribution due to tolerances of the voltage divider components, stray

259 capacitances and differences in recovery charge of thyristors
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260 3.3 Abbreviations
261 MVU multiple valve (unit)
262 SIPL switching impulse protective level
263 LIPL lightning impulse protective level
264 STIPL steep-front impulse protective level
265 4 Service conditions
266 4.1 General

267 Thyristor valves shall be able to operate continuously and reliably under the specified service

268 conditions throughout their entire service life except for maintenances. Such conditions are essential

269 to define the ratings and characteristics of the thyristor valves, and mainly include the environmental

270 conditions of valve halls under which thyristor valves will be required to operate, system conditions

271 directly related to the design and operation of thyristor valves, main technical parameters of 6-pulse

272 bridges required by the system design, and any other conditions provided by the purchaser. Some of

273 these conditions may not be applicable depending on the HVDC system design.
274 4.2 Environmental conditions
275 4.2.1 Site altitude

276 The altitude of the HVDC substation above sea-level shall be provided for insulation design of thyristor

277 valves.

278 For external insulation (as defined in clause 3.1.3 of IEC 60700-1), the insulation level of thyristor

279 valves under standardized reference atmospheric conditions shall be determined in accordance with

280 clause 4.2 of IEC 60700-1.

281 For internal insulation (as defined in clause 3.1.3 of IEC 60700-1), clause 8.2 of IEC 60700-1 shall be

282 referred to.
283 4.2.2 Air temperature and humidity range in valve halls

284 The maximum temperature and minimum relative humidity inside valve halls shall be considered in the

285 atmospheric correction according to clause 4.2 of IEC 60700-1. In addition, the air temperature and the

286 relative humidity in the valve hall shall be considered to prevent condensation on any surface of

287 components within the valve hall.
288 4.2.3 Cleanness in valve halls

289 The cleanness in valve halls (e.g. equivalent salt deposit density on the surface of insulators and

290 insulating materials) shall be provided for determination of creepage distances of thyristor valves. Dust

291 and pollution in valve halls shall be kept as low as possible to avoid un-economical increase of

292 creepage distances of thyristor valves.
293 4.2.4 Seismic conditions

294 Thyristor valves shall have the ability to withstand seismic stresses and to maintain their function

295 without failure during and after an earthquake of any specified intensity that may occur at the location

296 of the HVDC substation. Maximum expected horizontal and vertical acceleration along with the

297 frequency range of oscillations shall be provided.
298 4.3 System conditions
299 4.3.1 General information of the system
300 This part shall include at least the following information：
301 a) the purpose of the project, and
302 b) rated power, and
303 c) direction of power flow, and
304 d) converter configuration, including a simple one-line diagram, and
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305 e) converter operating modes such as monopolar, bipolar, parallel or multi-terminal, and

306 f) interface information.

307 NOTE1 For long distance HVDC transmission systems, the most commonly used converter unit configuration is one 12 pulse

308 group per pole or two 12 pulse groups in series connection or parallel connection per pole. Each valve group i

...