IEC 62590-3-1:2022

IEC 62590-3-1 ®
Edition 1.0 2022-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Railway applications – Fixed installations – Electronic power converters –
Part 3-1: AC traction applications – Electronic power compensators

Applications ferroviaires – Installations fixes – Convertisseurs electroniques de
puissance –
Partie 3-1: Applications de traction en courant alternatif – Compensateurs
électroniques de puissance
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IEC 62590-3-1 ®
Edition 1.0 2022-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Railway applications – Fixed installations – Electronic power converters –

Part 3-1: AC traction applications – Electronic power compensators

Applications ferroviaires – Installations fixes – Convertisseurs electroniques de

puissance –
Partie 3-1: Applications de traction en courant alternatif – Compensateurs

électroniques de puissance
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 45.060.01 ISBN 978-2-8322-4774-7

– 2 – IEC 62590-3-1:2022 © IEC 2022
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms, definitions and abbreviated terms . 9
3.1 Terms and definitions. 9
3.2 Abbreviated terms . 14
4 Types of electronic power compensators . 14
4.1 General . 14
4.2 Single-phase equipment which injects reactive power into a 1AC traction
system . 17
4.2.1 General . 17
4.2.2 Equipment installed on the far end or middle of a 1AC traction system . 17
4.2.3 Equipment installed on the near end of a 1AC traction system . 18
4.3 Multi-phase equipment connected to the 1AC traction side . 18
4.3.1 General . 18
4.3.2 Equipment exchanging active power between a pair of different 1AC
circuits and/or injecting reactive power into 1AC circuits . 18
4.3.3 Application of Steinmetz principle . 21
4.3.4 Equipment connected to the traction side of the V-connection
transformer . 22
4.4 Application on 3AC power network . 23
4.4.1 General . 23
4.4.2 Equipment connected to the 3AC power network side of a traction
transformer . 23
5 Design and integration . 25
5.1 General . 25
5.2 Survey of power quality criteria . 26
5.3 Survey of the condition of the 3AC power network . 26
5.4 Traction load requirements . 26
5.5 Estimation of the power quality without any countermeasures . 26
5.5.1 General . 26
5.5.2 Calculation of voltage drop in a 1AC traction system . 26
5.5.3 Calculation of three-phase imbalance at the interface to 3AC power
network . 27
5.5.4 Calculation of power factor at the interface to 3AC power network . 27
5.6 Choice of the countermeasures . 27
5.7 Evaluation of the electronic power compensator . 27
5.8 Specification of the electronic power compensator . 28
5.8.1 General . 28
5.8.2 Coordination with other systems . 28
6 Performance requirements . 28
6.1 General . 28
6.1.1 Rating . 28
6.1.2 Number of connected phases . 29
6.1.3 Temperature rise . 29
6.1.4 Losses and efficiency . 29

6.2 Control and protective function . 30
6.2.1 Start and stop sequence . 30
6.2.2 Control function . 31
6.2.3 Protective function . 31
6.3 Electromagnetic compatibility (EMC) . 31
6.4 Harmonics . 32
6.5 Failure conditions for the electronic power compensator . 32
6.6 Mechanical characteristics . 32
6.6.1 General . 32
6.6.2 Safety requirements for maintenance . 33
6.6.3 Environmental conditions . 33
6.6.4 Degree of protection . 33
6.7 Electrical safety requirements for maintenance . 33
6.8 Rating plate . 33
7 Tests . 34
7.1 Test category . 34
7.1.1 General . 34
7.1.2 Type test . 34
7.1.3 Routine test . 34
7.1.4 Large equipment . 35
7.1.5 Overview of tests . 35
7.2 Test items . 36
7.2.1 Visual inspection . 36
7.2.2 Test of accessory and auxiliary components . 36
7.2.3 Insulation test . 36
7.2.4 Start and stop sequence test . 37
7.2.5 Checking of the protective functions . 37
7.2.6 Control function test . 37
7.2.7 Light load functional test . 37
7.2.8 Load test . 38
7.2.9 Temperature rise test . 38
7.2.10 Power loss determination. 38
7.2.11 Acoustic noise measurement . 38
7.2.12 EMC test . 38
7.2.13 Harmonic measurement . 39
7.2.14 Degree of protection test . 39
Annex A (informative) Calculation of voltage drop in a 1AC traction system . 40
Annex B (informative) Calculation of three-phase imbalance at the interface to a 3AC
power network . 41
Annex C (informative) Examples of limits of power quality at the interface to a 3AC
power network . 43
C.1 General . 43
C.2 Examples of limits of three-phase imbalance . 43
C.3 Examples of limits of harmonics . 44
C.3.1 General . 44
C.3.2 Japan . 45
C.3.3 China . 45
C.3.4 France . 46
Bibliography . 47

– 4 – IEC 62590-3-1:2022 © IEC 2022

Figure 1 – Example of the possible electrical position of electronic power
compensators . 15
Figure 2 – Single-phase equipment installed on the far end or middle of a 1AC traction
system . 17
Figure 3 – Single-phase equipment installed on the near end of a 1AC traction system . 18
Figure 4 – Equipment exchanging active power between a pair of orthogonal 1AC
circuits and/or injecting reactive power into 1AC circuits . 20
Figure 5 – Application of Steinmetz principle . 22
Figure 6 – Equipment connected to traction side of the V-connection traction
transformer . 23
Figure 7 – Equipment which reduces imbalance at the 3AC power network side of a
traction transformer . 24
Figure 8 – Equipment which reduces imbalance generated in multiple traction
substations as a whole . 25
Figure A.1 – Calculation of voltage drop in a 1AC traction system. 40
Figure B.1 – Typical interface methods between power network and 1AC traction
system . 41

Table 1 – Types of typical electronic power compensators . 16
Table 2 – Immunity level . 32
Table 3 – Overview of tests. 35
Table B.1 – Formulae to calculate voltage imbalance at primary side of a traction

transformer . 41
Table C.1 – Examples of limits of three-phase imbalance . 44
Table C.2 – Limitation of harmonic content in Japan . 45
Table C.3 – Limitation of harmonic content in China . 45
Table C.4 – Factors for limitation of harmonic content in France . 46

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
RAILWAY APPLICATIONS – FIXED INSTALLATIONS –
ELECTRONIC POWER CONVERTERS –
Part 3-1: AC traction applications –
Electronic power compensators
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
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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) 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.
IEC 62590-3-1 has been prepared by IEC technical committee 9: Electrical equipment and
systems for railways. It is an International Standard.
The text of this International Standard is based on the following documents:
Draft Report on voting
9/2843/FDIS 9/2864/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.

– 6 – IEC 62590-3-1:2022 © IEC 2022
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
– Fixed installations – Electronic power converters, can be found on the IEC website.
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,
• replaced by a revised edition, or
• amended.
INTRODUCTION
Single-phase AC traction systems are typically used for railway lines with high power load up
to the double-digit MW range. The nature of the loads serving the intended traffic in those
railway lines leads to permanent power fluctuations. Due to their inherent structure, single-
phase traction systems are prone to having difficulty with power quality indicators such as power
factor, voltage fluctuation and/or imbalance within the electric traction system and/or the
feeding three-phase power network. In order to improve the power quality, an electronic power
compensator can be applied.
Components of electronic power compensators especially electronic power converters must
withstand the more rugged electric environment when compared with those for other industrial
use, due to the nature of electric traction systems mentioned above. This includes not only high
load fluctuation, but also frequent switching operation with inrush current and short circuits
caused by faults on the overhead contact line systems. Therefore, specific requirements are
needed in addition to the common requirements for converters for other industrial use.
This document defines typical system configurations and basic requirements as well as
appropriate test methods for electronic power compensators used for single-phase AC traction
systems. This document is intended for the use by railway operators, manufacturers and system
integrators.
– 8 – IEC 62590-3-1:2022 © IEC 2022
RAILWAY APPLICATIONS – FIXED INSTALLATIONS –
ELECTRONIC POWER CONVERTERS –
Part 3-1: AC traction applications –
Electronic power compensators
1 Scope
This document specifies the requirements and test methods for electronic power compensators
for 1AC traction systems. This equipment is used to improve electric power quality inside the
electric traction system and/or at the interface to the 3AC power network, applying power
electronics technology.
This document applies to equipment which is installed to achieve one or more of the following
objectives as its function(s):
• to mitigate voltage fluctuation;
• to improve power factor;
• to reduce imbalance at the interface to the 3AC power network.
NOTE In some cases, this type of equipment is used to reduce harmonics from the traction load towards the 3AC
power network, and for energy saving.
The equipment designed to conform to each particular installation site and the packaged
equipment for generic use both fall within the scope of this document.
This document applies to equipment with all possible configurations to implement different
technical solutions for compensation, but equipment consisting of only passive components is
excluded.
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 60050-151:2001, International Electrotechnical Vocabulary (IEV) – Part 151: Electrical and
magnetic devices
IEC 60050-151:2001/AMD1:2013
IEC 60050-151:2001/AMD2:2014
IEC 60050-151:2001/AMD3:2019
IEC 60050-151:2001/AMD4:2020
IEC 60050-151:2001/AMD5:2021
IEC 60146-1-1:2009, Semiconductor converters – General requirements and line commutated
converters – Part 1-1: Specification of basic requirements
IEC 60146-2:1999, Semiconductor converters – Part 2: Self-commutated semiconductor
converters including direct d.c. converters
IEC 60529, Degrees of protection provided by enclosures (IP Code)

IEC 60850, Railway applications – Supply voltages of traction systems
IEC 61000-4-30:2015, Electromagnetic compatibility (EMC) – Part 4-30: Testing and
measurement techniques – Power quality measurement methods
IEC 61000-4-30:2015/AMD1:2021
IEC 61936-1, Power installations exceeding 1 kV AC and 1,5 kV DC – Part 1: AC
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 62313, Railway applications – Power supply and rolling stock – Technical criteria for the
coordination between power supply (substation) and rolling stock
IEC 62590:2019, Railway applications – Fixed installations – Electronic power converters for
substations
IEC 62695:2014, Railway applications – Fixed installations – Traction transformers
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 62590:2019 and the
following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1.1
power quality
characteristics of the electric current, voltage and frequency at a given point in an electric power
system, evaluated against a set of reference technical parameters
Note 1 to entry: These parameters might, in some cases, relate to the compatibility between electricity supplied in
an electric power system and the loads connected to that electric power system.
[SOURCE: IEC 60050-614:2016, 614-01-01]
3.1.2
power factor
under periodic conditions, ratio of the absolute value of the active power P to the apparent
power S:
P
λ=
S
Note 1 to entry: Under sinusoidal conditions, the power factor is the absolute value of the active factor.
[SOURCE: IEC 60050-131:2002, 131-11-46]

– 10 – IEC 62590-3-1:2022 © IEC 2022
3.1.3
compensate
improve power quality at a certain point of the circuit
3.1.4
electric traction 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 systems,
– electric installations, which are supplied from contact lines either directly or via a transformer,
– 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 − third dash in the list of the Note 1 to
entry was removed.]
3.1.5
1AC traction system
single phase traction system
electric traction system operating with single phase AC
Note 1 to entry: The system includes auto-transformer system.
3.1.6
near end
area in electric traction system close to the traction substation
Note 1 to entry: This term is typically used for the single-side-fed electric traction systems.
3.1.7
far end
area in electric traction system most distant from the traction
substation, typically near a sectioning post
Note 1 to entry: This term is typically used for the single-side-fed electric traction systems.
3.1.8
feeding section
electric section of the route fed by individual track feeder circuit-breakers within the area
supplied by one or more substations
[SOURCE: IEC 60050-811:2017, 811-36-25]
3.1.9
3AC power network
three phase power network
three-phase electric circuit or set of electric circuits, interconnected or having intentional
capacitive or inductive coupling between them
Note 1 to entry: In this document, this term is used to indicate an upstream power supply network.
3.1.10
traction unit
locomotive, motor coach or train-unit
[SOURCE: IEC 60050-811, 811-02-04]

3.1.11
voltage drop
change of the voltage at the location of traction unit due to
impedance of electric traction system as well as impedance of the 3AC power network,
measured when traction current flows from or into traction units
3.1.12
voltage fluctuation
series of supply voltage changes or continuous variation of the
RMS or peak value of the voltage
Note 1 to entry: Whether the RMS or peak value is chosen depends upon the application, and which is used should
be specified.
[SOURCE: IEC 60050-161:1990, 161-08-05, modified – “series of voltage” was replaced with
“series of supply voltage”.]
3.1.13
voltage imbalance
in a polyphase system, condition in which the RMS values of the phase voltages or the phase
angles between consecutive phases are not all equal
[SOURCE: IEC 60050-161:1990, 161-08-09]
3.1.14
negative sequence component
one of the three symmetrical sequence components which exists
only in an unsymmetrical three-phase system of sinusoidal quantities and which is defined by
the following complex mathematical expression:
X = (X + a X + aX )
2 L1 L2 L3
where a is the 120-degree operator, and X , X and X are the complex expressions of the
L1 L2 L3
phase quantities concerned, and where X denotes the system current or voltage phasors
[SOURCE: IEC 60050-448:1995, 448-11-28]
3.1.15
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
[SOURCE: IEC 60050-551:1998, 551-12-01, modified – Note and Figure 1 were removed.]
3.1.16
self-commutation
commutation where the commutating voltage is supplied by components within the converter or
the electronic switch
[SOURCE: IEC 60050-551:1998, 551-16-15]
3.1.17
line-commutation
external commutation where the commutating voltage is supplied by the line
[SOURCE: IEC 60050-551:1998, 551-16-12]

– 12 – IEC 62590-3-1:2022 © IEC 2022
3.1.18
electronic power compensator
EPC
equipment to improve power quality of the circuit to which it is connected, controlling current
and/or voltage by use of electronic power converters
3.1.19
static var compensator
SVC
electronic power compensator adjusting reactive power
Note 1 to entry: The whole arrangement consists of fixed elements and adjustable elements. Line-commutated or
self-commutated converters are examples of adjustable elements.
3.1.20
balancer
electronic power compensator to reduce imbalance
Note 1 to entry: A positive side effect of a balancer is reducing voltage fluctuation and/or improving power factor in
the 1AC traction system as well as the 3AC power network.
3.1.21
railway static power conditioner
RPC
set of converters which exchanges active power between different sections in the electric
traction system as well as injects reactive power
Note 1 to entry: Currently, the only configuration that has been used in the already commissioned RPC is that which
consists of a pair of self-commutated single-phase inverters connected back-to-back to each other through a common
DC link.
Note 2 to entry: It is used to connect two feeding sections supplied by two traction substations, as well as two
feeding sections supplied by two single-phase voltage sources of different phases from the same traction substation.
3.1.22
STATCOM
SVG
static var compensator using set of self-commuted converters
Note 1 to entry: “STATCOM” is used in Europe and “SVG” is used in Japan.
3.1.23
Steinmetz principle
principle for balancing voltage and/or current of an unbalanced 3AC circuit by applying reactive
load between two or more pairs of phases
3.1.24
Scott connection
method of interconnecting the windings of two single-phase transformers for the transformation
of three-phase voltages to two-phase voltages or vice versa
Note 1 to entry: The voltage and current of 3AC side will balance when the two loads of two 1AC side circuits are
equal.
[SOURCE: IEC 60050-421:1990, 421-10-06, modified – Note 1 to entry was added.]
3.1.25
V-connection
two single phase loads between 2 different pairs of phases of a 3AC power network
Note 1 to entry: This leads statistically to a better-balanced load than one combined single-phase load.

3.1.26
rated capacity
capacity of electronic power compensator to fulfil its main
purpose, where calculation method and condition of equipment for measurement are defined
depending on the purpose and configuration of the equipment
Note 1 to entry: Typical rated capacity is expressed in active power, reactive power, apparent power or current.
3.1.27
rated voltage
voltage of electronic power compensator to operate, where
part and condition of equipment for measurement are defined depending on the purpose and
configuration of the equipment
3.1.28
rated current
current of electronic power compensator to operate, where
part and condition of equipment for measurement are defined depending on the purpose and
configuration of the equipment
3.1.29
rated frequency
frequency of electronic power compensator to operate,
where part and condition of equipment for measurement are defined depending on the purpose
and configuration of the equipment
Note 1 to entry: Intended operational frequency of the electronic power converter is taken from IEC 60850.
3.1.30
conventional efficiency
η
power efficiency determined from calculation and/or measurement using the specified method
Note 1 to entry: Especially for large equipment as explained in 7.1.4, it is sometimes difficult to measure the power
efficiency directly by testing equipment with rated load due to various restrictions.
3.1.31
control function
function intended to regulate the behaviour of equipment or systems
[SOURCE: IEC 61892-2:2019, 3.9]
3.1.32
protective function
function that operates to prevent harm to persons and/or damage
to equipment
3.1.33
immunity level
specified value of an electrical disturbance below which the equipment is
designed to meet the required performances or continue operation or avoid damage
[SOURCE: IEC 62590:2019, 3.11.2, modified − converter was replaced with equipment.]

– 14 – IEC 62590-3-1:2022 © IEC 2022
3.1.34
type test
conformity test made on one or more items representative of the production
Note 1 to entry: In the context of this document, the word “type” expresses a group of products that has completely
same design. The products with similar design but different ratings are considered as different type.
[SOURCE: IEC 60050-151:2001, 151-16-16, modified – Note 1 to entry was added.]
3.1.35
routine test
conformity test made on each individual item during or after manufacture
[SOURCE: IEC 60050-151:2001, 151-16-17]
3.2 Abbreviated terms
EPC electronic power compensator
RPC railway static power conditioner
STATCOM static synchronous compensator
SVC static var compensator
SVG static var generator
TCR thyristor controlled reactor
4 Types of electronic power compensators
4.1 General
The type of electronic power compensators is categorized as follows:
a) type of compensation:
1) single-phase compensation by injection of reactive power into 1AC traction system;
2) multi-phase compensation by coordination of active and/or reactive power at the 1AC
traction system side of a traction transformer;
– by exchange of active power between phases and/or circuits;
– by coordination of reactive power in phases.
3) multi-phase compensation by coordination of active and/or reactive power at the 3AC
power network side of a traction transformer.
b) electrical position of installation in the electric traction system:
1) the far end, intermediate or the near end of a 1AC traction system;
2) 1AC traction system side of a traction transformer;
3) 3AC power network side of a traction transformer, and possibly the receiving point of a
traction substation or transmitting point of a 3AC substation for power transmission
dedicated to traction.
c) one or more purpose and function:
1) reduction of voltage drop and/or voltage fluctuation inside 1AC traction system;
2) peak load reduction
3) improvement of power factor on 3AC power network side;
4) mitigation of voltage fluctuation on 3AC power network side;
5) mitigation of imbalance on 3AC power network side;
6) mitigation of harmonics from traction load towards 3AC power network.

d) type of commutation:
1) self-commutation;
2) line-commutation.
NOTE 1 Line-commutation type equipment is no longer the state of the art, but is still used around the world. It is
noted that a lot of harmonic issues often rise with this type of installation.
NOTE 2 An equivalent variable reactance element can be realized by using a fixed element in combination with a
controlled element. The most common example is a fixed capacitance in combination with a TCR. Combination of
fixed elements with converters using self-commuting principle is also possible.
NOTE 3 There may be other compensation methods besides the ones described in Clause 4.
Figure 1 shows an example of the possible electrical installation position of electronic power
compensators. The power quality may be improved by one piece of equipment or a combination
of different EPC.
The following subclauses from 4.2 to 4.4 describe typical technical solutions for compensation
and configuration of equipment to implement their application around the world, as summarised
in Table 1. However, this description is not exhaustive, and does not intend to prevent any other
types, including future ones, from being selected.
NOTE 4 For simplification, active power losses in the EPCs are neglected in all figures in subclauses 4.2 through
4.4.
Figure 1 – Example of the possible electrical position of electronic power compensators

– 16 – IEC 62590-3-1:2022 © IEC 2022

Table 1 – Types of typical electronic power compensators
Type of compensation Electrical position Purpose and function Control strategy Type of rated capacity Example of Sub-
equipment clause
Single-phase compensation by • far end or middle of • voltage drop compensation • AC voltage control • reactive power, in SVC 4.2.2
injection of reactive power into 1AC traction MVar
a 1AC traction system system
• near end of 1AC • power factor compensation • reactive power control • reactive power, in SVC 4.2.3
traction system MVar
Multi-phase compensation by • near end of 1AC • three-phase imbalance • active power control • apparent power, in RPC 4.3.2
coordination of active and/or traction system compensatio
...