EN IEC 62590-1:2025

SLOVENSKI STANDARD
01-september-2025
Železniške naprave - Elektronski elektroenergetski pretvornik za fiksne postroje -
1. del: Splošne zahteve
Railway applications - Electronic power converters for fixed installations - Part 1: General
requirements
Bahnanwendungen- Leistungselektronische Stromrichter für ortsfeste Anlagen - Teil 1:
Allgemeine Anforderungen
Applications ferroviaires - Convertisseurs électroniques de puissance pour installations
fixes - Partie 1: Exigences générales
Ta slovenski standard je istoveten z: EN IEC 62590-1:2025
ICS:
29.200 Usmerniki. Pretvorniki. Rectifiers. Convertors.
Stabilizirano električno Stabilized power supply
napajanje
45.040 Materiali in deli za železniško Materials and components
tehniko for railway engineering
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 62590-1

NORME EUROPÉENNE
EUROPÄISCHE NORM June 2025
ICS 45.060.01; 29.280
English Version
Railway applications - Electronic power converters for fixed
installations - Part 1: General requirements
(IEC 62590-1:2025)
Applications ferroviaires - Convertisseurs électroniques de Bahnanwendungen - Leistungselektronische Stromrichter
puissance pour installations fixes - Partie 1: Exigences für ortsfeste Anlagen - Teil 1: Allgemeine Anforderungen
générales (IEC 62590-1:2025)
(IEC 62590-1:2025)
This European Standard was approved by CENELEC on 2025-06-19. CENELEC members are bound to comply with 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
Management 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
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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Türkiye and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2025 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 62590-1:2025 E

European foreword
The text of document 9/3160/FDIS, future edition 1 of IEC 62590-1, prepared by TC 9 "Electrical
equipment and systems for railways" was submitted to the IEC-CENELEC parallel vote and approved
by CENELEC as EN IEC 62590-1:2025.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2026-06-30
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2028-06-30
document have to be withdrawn
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
Any feedback and questions on this document should be directed to the users’ national committee. A
complete listing of these bodies can be found on the CENELEC website.
Endorsement notice
The text of the International Standard IEC 62590-1:2025 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standard indicated:
IEC 60076-10 NOTE Approved as EN 60076-10
IEC 60146-1-1 NOTE Approved as EN IEC 60146-1-1
IEC 60146-2:1999 NOTE Approved as EN 60146-2:2000 (not modified)
IEC 61000-3 (series) NOTE Approved as EN 61000-3 (series)
IEC 62924 NOTE Approved as EN 62924
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments)
applies.
NOTE 1  Where 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.cencenelec.eu.
Publication Year Title EN/HD Year
IEC 60071-1 - Insulation co-ordination - Part 1: Definitions, EN IEC 60071-1 -
principles and rules
IEC 60364-1 - Low-voltage electrical installations - Part 1: HD 60364-1 -
Fundamental principles, assessment of
general characteristics, definitions
IEC 60529 - Degrees of protection provided by enclosures EN 60529 -
(IP Code)
IEC 60664-1 - Insulation coordination for equipment within EN IEC 60664-1 -
low-voltage supply systems - Part 1:
Principles, requirements and tests
IEC 60721 series Classification of environmental conditions EN 60721 series
IEC 60850 - Railway applications - Supply voltages of EN 50163 -
traction systems
IEC 61000-2-12 - Electromagnetic compatibility (EMC) - Part 2- EN 61000-2-12 -
12: Environment - Compatibility levels for
low-frequency conducted disturbances and
signalling in public medium-voltage power
supply systems
IEC 61936-1 - Power installations exceeding 1 kV AC and EN IEC 61936-1 -
1,5 kV DC - Part 1: AC
IEC 61992-7-1 2006 Railway applications - Fixed installations - DC EN 50123-7-1 2003
switchgear - Part 7-1: Measurement, control
and protection devices for specific use in d.c.
traction systems - Application guide
IEC 62236-2 - Railway applications - Electromagnetic EN 50121-2 -
compatibility -- Part 2: Emission of the whole
railway system to the outside world
IEC 62236-5 - Railway applications - Electromagnetic EN 50121-5 -
compatibility -- Part 5: Emission and immunity
of fixed power supply installations and
apparatus
Publication Year Title EN/HD Year
IEC 62497-1 2010 Railway applications - Insulation coordination EN 50124-1 -
- Part 1: Basic requirements - Clearances
and creepage distances for all electrical and
electronic equipment
IEC 62313 - Railway applications - Power supply and EN 50388 -
rolling stock - Technical criteria for the
coordination between power supply
(substation) and rolling stock
IEC 62695 - Railway applications - Fixed installations - EN 50329 -
Traction transformers
IEC 62590-1 ®
Edition 1.0 2025-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Railway applications – Electronic power converters for fixed installations –
Part 1: General requirements
Applications ferroviaires – Convertisseurs électroniques de puissance pour
installations fixes –
Partie 1: Exigences générales
ICS 45.060.01, 29.280 ISBN 978-2-8327-0402-8

IEC 62590-1:2025-05(en-fr)
– 2 – IEC 62590-1:2025 © IEC 2025
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms, definitions, principal letter symbols, abbreviated terms and symbols . 9
3.1 Terms and definitions . 9
3.2 Principal letter symbols . 13
3.3 Abbreviated terms . 14
3.4 Symbols . 14
4 System configurations . 15
4.1 General configurations . 15
4.2 Components of an electronic power converter . 15
4.3 Types of converters . 16
4.3.1 General overview . 16
4.3.2 3AC to DC converter . 16
4.3.3 DC converter . 17
4.3.4 3AC to 1AC converters . 17
4.3.5 1AC to 1AC converter . 18
4.3.6 1AC converter . 18
4.3.7 3AC converter . 19
5 Performance requirements. 19
5.1 Environmental conditions . 19
5.1.1 General . 19
5.1.2 Storage. 19
5.1.3 Transportation and handling . 19
5.1.4 Operating conditions including off-load periods . 20
5.1.5 Vibrations . 20
5.2 Insulation coordination . 20
5.3 Voltage range conditions . 21
5.4 Frequency range conditions . 21
5.5 Harmonics in connected systems . 21
5.5.1 General . 21
5.5.2 3AC power network side . 21
5.5.3 Traction power supply side . 22
5.6 Losses and efficiency . 22
5.7 Load requirements, duty class and load cycles . 23
5.7.1 General . 23
5.7.2 Rated current and duty class . 23
5.7.3 Load cycle . 23
5.8 Short time withstand current . 23
5.9 Cooling methods . 23
5.9.1 General . 23
5.9.2 Letters to be used . 23
5.9.3 Arrangement of letters . 24
5.10 Interlocking . 25
5.11 Mechanical conditions . 25

IEC 62590-1:2025 © IEC 2025 – 3 –
5.11.1 General . 25
5.11.2 Earthing . 25
5.11.3 Degree of protection . 26
5.12 Failure modes . 26
5.13 Audible sound . 27
5.14 Marking . 27
5.14.1 Rating plate . 27
5.14.2 Main circuit terminals . 27
6 Tests . 27
6.1 General requirements . 27
6.1.1 General . 27
6.1.2 Type test . 27
6.1.3 Routine test . 28
6.1.4 Overview of tests . 28
6.2 Test items . 29
6.2.1 Visual inspection . 29
6.2.2 Test of accessory and auxiliary components . 29
6.2.3 Insulation test . 30
6.2.4 Operational sequence test . 31
6.2.5 Checking of protective functions . 31
6.2.6 Control function test . 32
6.2.7 Light load functional test . 32
6.2.8 Load test . 32
6.2.9 Inherent voltage drop . 32
6.2.10 Temperature rise test . 32
6.2.11 Short time withstand current . 36
6.2.12 Power loss determination . 36
6.2.13 Audible Sound . 36
6.2.14 EMC test . 36
6.2.15 Harmonic test . 36
6.2.16 Power factor measurement . 37
6.2.17 Mechanical test . 37
Annex A (normative) Standardized duty classes. 38
Annex B (informative) Duty cycle test with limited rate of rise . 40
Annex C (informative) Traction load and duty cycle . 42
C.1 Background. 42
C.2 Evaluation of traction load . 42
C.3 Transformation of time-weighted RMS into rated current and duty class . 43
C.4 Examples . 44
C.4.1 Evaluation of traction load . 44
C.4.2 Benefit of using rated current I and duty class . 45
N
C.5 Transformation of traction load into a rated current in conjunction with a duty
class . 46
Annex D (informative) Typical load cycles . 49
D.1 General . 49
D.2 Cycle examples . 49
Annex E (informative) Relationship between user and manufacturer . 51
Bibliography . 53

– 4 – IEC 62590-1:2025 © IEC 2025

Figure 1 – General configuration . 15
Figure 2 – General configuration of 3AC to DC converters . 17
Figure 3 – General configurations of DC converters . 17
Figure 4 – General configuration of 3AC to 1AC converters . 18
Figure 5 – General configuration of 1AC to 1AC converters . 18
Figure 6 – General configuration of 1AC converters . 18
Figure 7 – General configuration of 3AC converters . 19
Figure 8 – Test cycle for a duty class . 34
Figure 9 – Determination of rise times. 35
Figure B.1 – comparison of duty cycle and test cycle . 40
Figure C.1 – Moving window in the time domain demonstrated on a theoretical traction
load 1 with 60 min cycle time . 44
Figure C.2 – Transfer of highest values from moving window calculation into the time-
weighted RMS graph . 45
Figure C.3 – Theoretical traction load 2, 10 min cycle time . 45
Figure C.4 – Time-weighted RMS values of theoretical traction load 1 and 2 . 46
Figure C.5 – Typical load current of a mass transit traction load . 47
Figure C.6 – Time-weighted RMS graph of the traction load in Figure C.5 . 48
Figure C.7 – Comparison of traction load with duty classes. 48
Figure D.1 – Examples for load cycles . 50
Figure E.1 – Relationship between user and manufacturer . 51

Table 1 – Converter types . 16
Table 2 – Minimum insulation level of the main circuit . 21
Table 3 – Letter symbols for cooling mediums and heat transfer agents . 24
Table 4 – Letter symbols for methods of circulation . 24
Table 5 – Summary of tests applicable to all converter types . 29
Table A.1 – Standardized duty classes . 39
Table B.1 – Example values . 41

IEC 62590-1:2025 © IEC 2025 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
RAILWAY APPLICATIONS –
ELECTRONIC POWER CONVERTERS FOR FIXED INSTALLATIONS –

Part 1: General requirements
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-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 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 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 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 accepted 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 international 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 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 should 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 damage 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 of the referenced publications is
indispensable for the correct application of this publication.
9) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
may be required to implement this document. However, implementers are cautioned that this may not represent
the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
IEC 62590 has been prepared by IEC technical committee 9: Electrical equipment and systems
for railways. It is an International Standard.
This document, in conjunction with the other parts of IEC 62590, cancels and replaces
IEC 62589:2010 and the former IEC 62590:2019.
This document includes the following significant technical changes with respect to
IEC 62589:2010 and the former IEC 62590:2019:
a) Split into common requirements and special requirements for different converters;
b) Interface Model for the different systems connected;
c) Split into circuits with their requirements like insulation coordination;
d) Energy efficiency addressed.

– 6 – IEC 62590-1:2025 © IEC 2025
The text of this International Standard is based on the following documents:
Draft Report on voting
9/3160/FDIS 9/3206/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
A list of all parts in the IEC 62590 series, published under the general title Railway applications
– Electronic power converters for fixed installations, can be found on the IEC website.
Future documents in this series will carry the new general title as cited above. Titles of existing
documents in this series will be updated at the time of the next edition.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
IEC 62590-1:2025 © IEC 2025 – 7 –
INTRODUCTION
Semiconductor converters for traction power supply differ from other converters for industrial
use due to special electrical service conditions and due to the large range of load variation and
the peculiar characteristics of the load.
For these reasons the IEC 60146 series does not fully cover the requirements of railway
applications and the decision was taken to have a specific series of standards for this use.
Specific requirements for the design of converter transformers for fixed installations of railway
applications are specified in IEC 62695.
This document defines common vocabulary and requirements. Other parts will cover different
applications. The whole series is listed below. Requirements in the specific parts have priority
over this document.
IEC 62590-1, Railway applications – Electronic Power Converters for fixed installations – Part 1:
General requirements
IEC 62590-2-1, Railway applications – Electronic Power Converters for fixed installations –
Part 2-1: DC traction applications – Uncontrolled rectifiers
IEC 62590-2-2, Railway applications – Electronic Power Converters for fixed installations –
Part 2-2: DC traction applications – Controlled converters
IEC 62590-3-1, Railway applications – Fixed installations – Electronic power converters –
Part 3-1: AC traction applications – Electronic power compensators
IEC 62590-3-2, Railway applications – Electronic Power Converters for fixed installations –
Part 3-2: AC traction applications – Static frequency converters

– 8 – IEC 62590-1:2025 © IEC 2025
RAILWAY APPLICATIONS –
ELECTRONIC POWER CONVERTERS FOR FIXED INSTALLATIONS –

Part 1: General requirements
1 Scope
This part of IEC 62590 specifies the common requirements and definitions for all power
converter applications in fixed installations for power supply of railway systems.
This document applies to fixed installations of following electric traction systems:
• railway networks,
• metropolitan transport networks including metros, tramways, trolleybuses and fully
automated transport systems, magnetic levitated transport systems, electric road systems.
This document applies to AC/DC converters, DC converters and AC converters. Converters for
improvement of power quality and for energy saving are also included.
Converters connected to electric traction systems feeding 3AC, 1AC or DC systems for auxiliary
purpose are not in the scope of this document but some aspects such as insulation coordination
and railway specific conditions can be referred to.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60071-1, Insulation co-ordination – Part 1: Definitions, principles and rules
IEC 60364-1, Low-voltage electrical installations – Part 1: Fundamental principles, assessment
of general characteristics, definitions
IEC 60529, Degrees of protection provided by enclosures (IP Code)
IEC 60664-1, Insulation coordination for equipment within low-voltage supply systems – Part 1:
Principles, requirements and tests
IEC 60721 (all parts), Classification of environmental conditions
IEC 60850, Railway applications – Supply voltages of traction systems
IEC 61000-2-12, Electromagnetic compatibility (EMC) – Part 2-12: Environment – Compatibility
levels for low-frequency conducted disturbances and signalling in public medium-voltage power
supply systems
IEC 61936-1, Power installations exceeding 1 kV AC and 1,5 kV DC – Part 1: AC

IEC 62590-1:2025 © IEC 2025 – 9 –
IEC 61992-7-1:2006, Railway applications – Fixed installations – DC switchgear – Part 7-1:
Measurement, control and protection devices for specific use in d.c. traction systems –
Application guide
IEC 62236-2, Railway applications – Electromagnetic compatibility – Part 2: Emission of the
whole railway system to the outside world
IEC 62236-5, Railway applications – Electromagnetic compatibility – Part 5: Emission and
immunity of fixed power supply installations and apparatus
IEC 62497-1:2010, Railway applications – Insulation coordination – Part 1: Basic requirements
– Clearances and creepage distances for all electrical and electronic equipment
IEC 62313, Railway applications – Power supply and rolling stock – Technical criteria for the
coordination between power supply (substation) and rolling stock
IEC 62695, Railway applications – Fixed installations – Traction transformers
3 Terms, definitions, principal letter symbols, abbreviated terms and symbols
For the purposes of this document, the following terms, definitions, principal letter symbols,
abbreviated terms and symbols apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1 Terms and definitions
3.1.1
electric traction power supply system
railway electric distribution network used to provide energy for rolling stock
Note 1 to entry: The system includes:
• contact line systems,
• return circuit of electric traction power supply systems,
• electric installations in power plants and substations, which are utilized solely for generation and distribution of
power directly to the contact line,
• electric installations of switching stations.
[SOURCE: IEC 60050-811:2017, 811-36-21, modified – "power supply" inserted in the term,
Note 1 to entry exclusion of the points "running rails of non-electrified lines in the vicinity of,
and conductively connected to the running rails of an electric traction power supply system",
and "electrical installations which are supplied from contact lines either directly or via a
transformer"]
3.1.2
DC traction power supply system
electric traction power supply system operating with DC

– 10 – IEC 62590-1:2025 © IEC 2025
3.1.3
single-phase traction power supply system
1AC traction power supply system
electric traction power supply system operating with single phase AC
Note 1 to entry: Autotransformer systems have a phase-shift of 180 electrical degrees between their poles.
Therefore, they are included in 1AC traction power supply systems.
3.1.4
electric power network
particular installations, substations, lines or cables for the transmission and distribution of
electricity
Note 1 to entry: The boundaries of the different parts of this network are defined by appropriate criteria, such as
geographical situation, ownership, voltage, etc.
Note 2 to entry: In this document, this term is used to indicate a power supply network from which an electric traction
power supply system receives electric power.
Note 3 to entry: A lot of synonyms are used indicating special properties like distribution network, transmission
network, national grid, upstream network, power grid or others. The term electric power network is chosen because
it is the most general.
[SOURCE: IEC 60050-601:1985, 601-01-02, modified – Notes 2 and 3 to entry have been
added]
3.1.5
three-phase power network
3AC power network
electric power network operating with three phases AC
3.1.6
electronic power converter
operative unit for electronic power conversion, comprising one or more electronic valve devices,
transformers and filters if necessary and auxiliaries if any
Note 1 to entry: In English, the two spellings "convertor" and "converter" are in use, and both are correct. In this
document, the spelling "converter" is used in order to avoid duplications.
[SOURCE: IEC 60050-551:1998, 551-12-01, modified – Figure not used, and parentheses
removed]
3.1.7
AC/DC converter
electronic converter for rectification or inversion or both
[SOURCE: IEC 60050-551:1998, 551-12-02]
3.1.8
rectifier
AC/DC converter for rectification
Note 1 to entry: For purpose of this document the rectifier includes the transformer. This is contradictory to common
language in which rectifier means only the valve device assembly and does not include the transformer.
[SOURCE: IEC 60050-551:1998, 551-12-07, modified – Note 1 to entry added]

IEC 62590-1:2025 © IEC 2025 – 11 –
3.1.9
inverter
AC/DC converter for inversion
Note 1 to entry: In English, the two spellings "invertor" and "inverter" are in use, and both are correct. In this
document the spelling "inverter" is used in order to avoid duplications.
[SOURCE: IEC 60050-551:1998, 551-12-10]
3.1.10
reversible converter
converter in which the direction of the power flow is reversible
[SOURCE: IEC 60050-551:1998, 551-12-37]
3.1.11
AC converter
converter for AC conversion
[SOURCE: IEC 60050-551:1998, 551-12-17]
3.1.12
DC converter
converter for DC conversion
[SOURCE: IEC 60050-551:1998, 551-12-27]
3.1.13
control equipment
entirety of devices and programs and, in a broader sense, all instructions and programs used
for the task of controlling
Note 1 to entry: Control equipment also comprises the process control station and instructions include operating
manuals.
[SOURCE: IEC 60050-351:2013, 351-56-24]
3.1.14
valve device assembly
electrically and mechanically combined assembly of electronic valve devices or stacks,
complete with all its connections and auxiliaries in its own mechanical structure
[SOURCE: IEC 60050-551:1998, 551-14-13, modified – Note omitted and adaptation to current
ISO/IEC directives]
3.1.15
commutation
in an electronic power converter, transfer of current from one conducting arm to the next to
conduct in sequence, without interruption of the current, both arms conducting simultaneously
during a finite time interval
[SOURCE: IEC 60050-551:1998, 551-16-01, modified –"the" between converter and transfer
replaced with ","]
– 12 – IEC 62590-1:2025 © IEC 2025
3.1.16
line commutation
line commutated
external commutation, where the commutating voltage is supplied by the line
Note 1 to entry: The term line refers to the line to line voltage of the feeding 3AC power network.
[SOURCE: IEC 60050-551:1998, 551-16-12, modified – Note 1 to entry has been added.]
3.1.17
self commutation
self commutated
commutation, where the commutating voltage is supplied by components within the converter
or the electronic switch
[SOURCE: IEC 60050-551:1998, 551-16-15]
3.1.18
nominal voltage
U
n
voltage by which a converter is designated
Note 1 to entry: Standardized values are given in IEC 60850.
3.1.19
rated continuous current
I
r
value of current which a converter is capable of carrying continuously without
damage, for specified service conditions
Note 1 to entry: The rated continuous current does not include overloads. If a specified overload is needed a
derating is necessary and a rated current in conjunction with a duty class is applied.
3.1.20
rated current
I
N
, current value the converter and parts of it is designed for in conjunction with a
duty class
Note 1 to entry: A converter and parts of it can have several pairs of rated current and duty class.
Note 2 to entry: The rated current for DC applications is always a mean value. The rated current for AC applications
is always an RMS value.
3.1.21
duty class
tabled representation of current capability and test values for standard design converters in
terms of current values and duration selected to represent a characteristic group of practical
applications
Note 1 to entry: The current values are expressed in per unit of the rated current I .
N
IEC 62590-1:2025 © IEC 2025 – 13 –
3.1.22
load cycle
conventional representation of the current demand to a converter
Note 1 to entry: The current values are expressed in A or in per unit of the rated current.
Note 2 to entry: The load cycle shows the repetitive variation of the loads with time and, hence, the load over or
under the rated load the converter is expected to carry.
[SOURCE: IEC 60050-811:2017, 811-28-38, modified – "group" removed, Notes 1 and 2 to
entry modified]
3.1.23
user
, entity which procures, installs and/or operates equipment, and agrees with the
manufacturer about the equipment characteristic
Note 1 to entry: A graphical representation of the relationship between user and manufacturer is given in Annex E.
3.1.24
manufacturer
entity which produces and/or distributes equipment, and agrees with the user
about the equipment characteristic
Note 1 to entry: A graphical representation of the relationship between user and manufacturer is given in Annex E.
3.1.25
cooling medium
liquid (for example water) or gas (for example air) which removes the heat from the equipment
3.1.26
direct cooling
method of cooling by which the cooling medium is in direct contact with the parts of the
equipment to be cooled, i.e. no heat transfer agent is used
3.1.27
indirect cooling
method of cooling in which a heat transfer agent is used to transfer heat from the part to be
cooled to the cooling medium
3.1.28
natural cooling
method of circulating the cooling medium or heat transfer agent which uses
the change of volumetric mass (density) with temperature
3.1.29
forced cooling
method of circulating the cooling medium or heat transfer agent by means of
blower(s), fan(s) or pump(s)
3.2 Principal letter symbols
f rated frequency on 3AC side of a converter
N3AC
rated current
I
N
I rated continuous current
r
U power frequency test voltage [SOURCE: IEC 62497-1]
a
U power frequency test voltage for verification of clearances [SOURCE: IEC 62497-1]
ac
– 14 – IEC 62590-1:2025 © IEC 2025
U nominal voltage
n
U rated voltage on 3AC side of a converter
N3AC
U rated impulse voltage [SOURCE: IEC 62497-1:2010, 3.4.7]
Ni
U rated insulation voltage [SOURCE: IEC 62497-1:2010, 3.4.4]
Nm
3.3 Abbreviated terms
AC Alternating Current
DC Direct Current
LV Low voltage
3.4 Symbols
The following symbols are used in this document:
AC/DC converter with optional indication of
power flow direction
DC
DC converter
DC
DC
DC converter with isolation between 2 electrical
circuits
DC
1 AC to 1 AC converter with isolation

1AC converter connected to 1 AC traction power
supply system only
3AC converter connected to a 3AC power
network only
IEC 62590-1:2025 © IEC 2025 – 15 –
4 System configurations
4.1 General configurations
The most common configuration for an electronic power converter supplying an electric traction
power supply system is shown in Figure 1. More detailed configurations are shown in Figure 2,
Figure 3 and Figure 4.
Figure 1 – General configuration
3AC power networks normally have a nominal voltage higher than 6 kV up to 500 kV. Applicable
standards are IEC 60071-1 for insul
...