TC 22 - Power electronic systems and equipment

IEC 61800-5-1:2022 specifies requirements for adjustable speed electrical power drive systems (PDS) or their elements, with respect to electrical, thermal, fire, mechanical, energy and other relevant hazards. It does not cover the driven equipment except for interface requirements. It applies to adjustable speed electrical PDS which include the power conversion, basic drive module (BDM)/complete drive module (CDM) control, and a motor or motors.
Excluded are traction and electric vehicle BDM/CDM.
It applies to low-voltage adjustable speed electrical PDS intended to feed a motor or motors from a BDM/CDM connected to phase-to-phase voltages of up to and including 1,0 kV AC (50 Hz or 60 Hz) and up to and including 1,5 kV DC. It also applies to high-voltage adjustable speed electrical PDS intended to feed a motor or motors from a BDM/CDM connected to phase-to-phase voltages of up to and including 35 kV AC (50 Hz or 60 Hz) and up to and including 52 kV DC.
This document also applies to PDS which intentionally emits or receives radio waves for the purpose of radio communication.
This edition includes the following significant technical changes with respect to the previous edition:
a) harmonization with IEC 62477-1:2022;
b) harmonization with UL 61800-5-1 and CSA C22.2 No. 274, including an annex with a list of national deviation which was considered not possible to harmonize within a reasonable timeframe;
c) more detailed information about the evaluation of components according to this document and relevant safety component standards;
d) updated requirement for mechanical hazards including multiple IP ratings.

IEC 61800-3:2022 specifies electromagnetic compatibility (EMC) requirements for adjustable speed power drive systems (PDSs) and machine tools (MTs). A PDS is an AC or DC motor drive including an electronic converter. Requirements are stated for AC and DC PDSs and MTs with input and/or output voltages (line-to-line voltage), up to 35 kV AC RMS. This document applies to equipment of all power ratings.
As a product EMC standard, this document can be used for the assessment of PDS and MT. It can also be used for the assessment of complete drive modules (CDM) or basic drive modules (BDM).
Traction applications and electric vehicles are excluded. Equipment which is defined as group 2 in CISPR 11:2015 is excluded.
This document does not give requirements for the electrical machine which converts power between the electrical and mechanical forms within the PDS. Requirements for rotating electrical machines are covered by the IEC 60034 series. In this document, the term "motor" is used to describe the electrical machine, whether rotary or linear, and regardless of the direction of power flow.
This document is applicable to BDMs, CDMs, PDSs and MTs with or without radio function. However, this document does not specify any radio transmission and reception requirements.
This document defines the minimum requirements for emission and immunity in the frequency range from 0 Hz to 400 GHz. Tests are not required in frequency ranges where no requirements are specified.
This fourth edition cancels and replaces the third edition published in 2017. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:  
extension of the scope to machine tools with one or more embedded PDS;
extension of the frequency range for radiated immunity tests to 6 GHz;
general updates in the normative part and the informative annexes.

IEC 60700-3:2022 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.

IEC 61800-5-1:2022 specifies requirements for adjustable speed electrical power drive systems (PDS) or their elements, with respect to electrical, thermal, fire, mechanical, energy and other relevant hazards. It does not cover the driven equipment except for interface requirements. It applies to adjustable speed electrical PDS which include the power conversion, basic drive module (BDM)/complete drive module (CDM) control, and a motor or motors.
Excluded are traction and electric vehicle BDM/CDM.
It applies to low-voltage adjustable speed electrical PDS intended to feed a motor or motors from a BDM/CDM connected to phase-to-phase voltages of up to and including 1,0 kV AC (50 Hz or 60 Hz) and up to and including 1,5 kV DC. It also applies to high-voltage adjustable speed electrical PDS intended to feed a motor or motors from a BDM/CDM connected to phase-to-phase voltages of up to and including 35 kV AC (50 Hz or 60 Hz) and up to and including 52 kV DC.
This document also applies to PDS which intentionally emits or receives radio waves for the purpose of radio communication.
This edition includes the following significant technical changes with respect to the previous edition:
a) harmonization with IEC 62477-1:2022;
b) harmonization with UL 61800-5-1 and CSA C22.2 No. 274, including an annex with a list of national deviation which was considered not possible to harmonize within a reasonable timeframe;
c) more detailed information about the evaluation of components according to this document and relevant safety component standards;
d) updated requirement for mechanical hazards including multiple IP ratings.
The contents of the corrigendum 1 (2023-09) have been included in this copy.

IEC 62477-1:2022 applies to power electronic converter systems (PECS), any specified accessories, and their components for electronic power conversion and electronic power switching, including the means for their control, protection, monitoring and measurement, such as with the main purpose of converting electric power, with rated system voltages not exceeding 1 000 V AC or 1 500 V DC.
This document also applies to PECS which intentionally emit or receive radio waves for the purpose of radio communication.
This document can also be used as a reference standard for product committees producing product standards for:
• adjustable speed electric power drive systems (PDS);
• standalone uninterruptible power systems (UPS);
• low voltage stabilized DC power supplies;
• bidirectional power converters.
For PECS and their specified accessories for which no product standard exists, this document provides minimum requirements for safety aspects.
This document has the status of a group safety publication in accordance with IEC Guide 104 for power electronic converter systems for solar, wind, tidal, wave, fuel cell or similar energy sources.
According to IEC Guide 104, one of the responsibilities of technical committees is, wherever applicable, to make use of basic safety publications and/or group safety publications in the preparation of their product standards.
Guidance for use of this group safety publication for product committees is given in Annex S.
This document
• establishes a common terminology for safety aspects relating to PECS,
• establishes minimum requirements for the coordination of safety aspects of interrelated parts within a PECS,
• establishes a common basis for minimum safety requirements for the PECS portion of products that contain PECS,
• specifies requirements to reduce risks of fire, electric shock, thermal, energy and mechanical hazards, during use and operation and, where specifically stated, during service and maintenance, and
• specifies minimum requirements to reduce risks with respect to PECS designed as pluggable and permanently connected equipment, whether it consists of a system of interconnected units or independent units, subject to installing, operating and maintaining the PECS in the manner prescribed by the manufacturer.
This document does not cover
• telecommunications apparatus other than power supplies to such apparatus,
• functional safety aspects as covered by, for example, IEC 61508 (all parts), and
• electrical equipment and systems for railways applications and electric vehicles.
The contents of the corrigendum of April 2024 have been included in this copy.

IEC TR 62543:2022 is available as IEC TR 62543:2022 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.
IEC TR 62543:2022 gives general guidance on the subject of voltage sourced converters (VSC) used for transmission of power by high voltage direct current (HVDC). It describes converters that are not only voltage sourced (containing a capacitive energy storage medium and where the polarity of DC voltage remains fixed) but also self-commutated, using semiconductor devices which can both be turned on and turned off by control action. The scope includes 2‑level and 3-level converters with pulse-width modulation (PWM), along with multi-level converters, modular multi-level converters and cascaded two-level converters, but excludes 2‑level and 3-level converters operated without PWM, in square-wave output mode. HVDC power transmission using voltage sourced converters is known as "VSC transmission". The various types of circuit that can be used for VSC transmission are described in this document, along with their principal operational characteristics and typical applications. The overall aim is to provide a guide for purchasers to assist with the task of specifying a VSC transmission scheme. Line-commutated and current-sourced converters are specifically excluded from this document. This edition includes the following significant technical changes with respect to the previous edition:
- in Clause 3, some redundant definitions which were identical to those listed in IEC 62747 have been deleted;
- in 4.3.4, description and diagrams have been added for the cases of a bipole with dedicated metallic return and a rigid bipole;
- in 4.4, mention is made of the bi-mode insulated gate transistor (BiGT) and injection enhanced gate transistor (IEGT) as possible alternatives to the IGBT;
- in 5.6, the reference to common-mode blocking reactors has been deleted since these are very rarely used nowadays.

IEC TR 63259:2022(E) provides guidelines for the application of water cooling systems for power electronics used in electrical transmission and distribution systems.
This document describes a kind of water cooling system, in which de-ionized water or de-ionized water mixed with other solutes is used as the heat transfer agent for the removal of heat from power electronic equipment. Water cooling system can be separated into main circuit, and control and protection system. Other cooling systems, in which de-ionized water is not the heat transfer agent, are excluded in this document.
This document provides guidance and supporting information for both purchaser(s) and potential supplier(s). It can be used as the basis for drafting a procurement specification and as a guide during project implementation.

IEC 61954:2021 is available as IEC 61954:2021 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.
IEC 61954:2021 defines type, production and optional tests on thyristor valves used in thyristor controlled reactors (TCR), thyristor switched reactors (TSR) and thyristor switched capacitors (TSC) forming part of static VAR compensators (SVC) for power system applications. The requirements of the document apply both to single valve units (one phase) and to multiple valve units (several phases). Clauses 4 to 7 detail the type tests, i.e. tests which are carried out to verify that the valve design meets the requirements specified. Clause 8 covers the production tests, i.e. tests which are carried out to verify proper manufacturing. Clauses 9 and 10 detail optional tests, i.e. tests additional to the type and production tests. This edition includes the following significant technical changes with respect to the previous edition: important clarifications were made in 4.4.1.2, 5.1.2.2, 5.1.3.2, 5.2.3.2, 6.1.2.2, 6.1.2.4, 6.1.3.2, 6.2.2.2, 6.2.2.4, 6.3.2.2 and 9.3.2.

IEC TR 62001-4:2021 is available as IEC TR 62001-4:2021 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC TR 62001:2021, which is a Technical Report, provides guidance on the basic data of AC side filters for high-voltage direct current (HVDC) systems and their components such as ratings, power losses, design issues and special applications, protection, seismic requirements, equipment design and test parameters.
This document covers AC side filtering for the frequency range of interest in terms of harmonic distortion and audible frequency disturbances. It excludes filters designed to be effective in the power line carrier (PLC) and radio interference spectra. It concerns the conventional AC filter technology and LCC (line-commutated converter) HVDC but much of this applies to any filter equipment for VSC (voltage sourced converter) HVDC. This edition includes the following significant technical change with respect to the previous edition:
- general updating of the document to reflect changes in practice;
- Annex A deleted as its content is covered by IEC 61803.

IEC TR 62001:2021(E), which is a Technical Report, provides guidance on the state-of-the art of VSC technology in relation to harmonics and predicted future developments, on the harmonic profile of present and predicted future VSC architectures and how they are characterised and modelled – as voltage sources, current sources, or otherwise. It also assesses the harmonic impedance of VSC and the possible impact on pre-existing background harmonics emanating from loads or generation units in the supply network and considers how VSC harmonics are assessed under current IEC standards and national regulations, and identify areas where improvements could be made, research can be needed, or other bodies consulted, for example when considering interharmonics. This document can be a reference source on the subject, which will also contain recommendations for use by those charged with modifying existing standards to adapt to VSC HVDC systems.

IEC TR 62001-1:2021 is available as IEC TR 62001-1:2021 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC TR 62001-1:2021 deals with the specification and design evaluation of AC side harmonic performance and AC side filters for HVDC schemes. It is intended to be primarily for the use of the utilities and consultants who are responsible for issuing the specifications for new HVDC projects and evaluating designs proposed by prospective suppliers. This document provides guidance on the specifications of AC filters for high-voltage direct current (HVDC) systems with line-commutated converters and filter performance calculation. The scope of this document covers AC side filtering for the frequency range of interest in terms of harmonic distortion and audible frequency disturbances. Where the term "HVDC converter" or "HVDC station" is referred to without qualification, in this document, it is understood to refer to LCC technology. It excludes filters designed to be effective in the power line carrier (PLC) and radio interference spectra. This edition includes the following significant technical changes with respect to the previous edition:
- general updating of the document to reflect changes in practice;
- 10.2.4 on fuseless capacitors has been transferred to IEC TR 62001-4;
- Clause 11 on future developments has been expanded;
- 10.3.3 and Annex F on voltage sourced converters have been deleted as their content is covered by IEC TR 62543.

IEC 62040-3:2021 establishes the performance and test requirements applied to movable, stationary and fixed electronic uninterruptible power systems (UPS) that
- are supplied from AC voltage not exceeding 1 000 V,
- deliver AC output voltage not exceeding 1 000 V,
- incorporate an energy storage device not exceeding 1 500 V DC, and
- have a primary function to ensure continuity of load power.
This document specifies performance and test requirements of a complete UPS and, where applicable, of individual UPS functional units. This document also includes UPS performance and test requirements related to UPS switches that interact with UPS functional units to maintain continuity of load power.
This document does not cover
- conventional AC and DC distribution boards and their associated switches,
- stand-alone static transfer systems covered by IEC 62310-3,
- rotary UPS covered by IEC 88528-11, and
- DC UPS covered by IEC 62040-5-3.
This edition includes the following significant technical changes with respect to the previous edition:
1) environmental conditions aligned with IEC 62040-1:2017 (UPS safety requirements);
2) compliance requirements included in all sub-clauses referenced in Table 5 UPS test schedule;
3) non-linear step load is no longer a type test and was removed from 6.4 in consistency with requirements for switch mode power supplies incorporating inrush current controls; this resulted in the performance classification coding being shortened from 8 to 7 characters (see 5.3.4);
4) free-fall test aligned with ISO 4180 (see 6.5.1.3);
5) multiple normal mode UPS test requirements introduced;
6) non-linear load requirements relaxed in Annex E in consistency with requirements for switch mode power supplies complying with the applicable limits for harmonic current in IEC 61000-3-2 and IEC 61000-3-12;
7) minimum UPS efficiency values referenced in Annex I became normative and are based on active output power rating and utilisation of weighting factors rather than on allowances related to isolation transformers, input harmonic current filters and input voltages.

IEC 61800-2:2021 applies to adjustable speed electric AC power drive systems, which include semiconductor power conversion and the means for their control, protection, monitoring, measurement and the AC motors.
It applies to adjustable speed electric power drive systems intended to feed AC motors from a BDM or CDM connected to line-to-line voltages up to and including 35 kV AC 50 Hz or 60 Hz and/or voltages up to and including 1,5 kV DC input side.
NOTE Adjustable speed electric DC power drive systems intended to feed DC motors are covered by IEC 61800-1.
This documents defines and describes a non-exhaustive list of criteria for the selection of BDM/CDM/PDS performance and functional attributes. This list is reviewed by the responsible parties to determine considerations for the design of device(s), equipment or system(s) with related testing specification. It also suggests a selection of performance and functional attributes for driven equipment and extended products. The performance and functional attributes focus on the following categories:
principal parts topology and classification of the PDS;
ratings, performance and functionality;
specifications for the environment in which the PDS is intended to be installed and operated;
other specifications which might be applicable when specifying a complete PDS.  Traction applications and electric vehicles are excluded from the scope of this document.
This document provides a non-exhaustive list from which minimum requirements can be used for the development of a specification between customer and manufacturer based on the application requirements. This same non-exhaustive list can be used by a manufacturer to determine the minimum requirements for a commoditised BDM/CDM/PDS without customer interaction based on the specified application of that BDM/CDM/PDS.
This third edition cancels and replaces the second edition published in 2015. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
a. the requirements from IEC 61800-4 for high-voltage PDS are now merged with requirements from IEC 61800-2:2015;
b. Clause 1 has been updated to introduce the new concept of Clause 4;
c. terms and definitions in Table 1 to Table 4 have been classified in logical order; classification in low voltage and high voltage has been considered in Table 5, and Figure 3 clarifies boundaries within BDM/CDM/PDS.
d. Clause 4 is new and creates the methods for evaluating a product to this document;
e. Clause 5 has been updated with respect to:  
specific content for high-voltage BDM/CDM/PDS;
description of the basic topology for BDM/CDM/PDS (5.2);
ratings and performance (5.3 and 5.4);
reference to applicable standards within the IEC 61800 series with respect to EMC (IEC 61800-3), electrical safety (IEC 61800-5-1), functional safety (IEC 61800-5-2), load duty aspects (IEC TR 61800-6), communication profiles (IEC 61800-7 series), power interface voltage (IEC TS 61800-8), and ecodesign (IEC 61800-9 series) to avoid conflicting requirements (5.5, 5.6, 5.7, 5.10, 5.11, 5.12);
update of requirement for ecodesign (5.8);
update of requirement for environmental evaluation (5.9);
implementation of requirement for explosive atmosphere (5.14);  f) Clause  REF _Ref51162898 \w \h 6 08D0C9EA79F9BACE118C8200AA004BA90B02000000080000000D0000005F00520065006600350031003100360032003800390038000000  has been updated with test requirement in order to provide a clear link between design requirement and test requirement;
g) Clause  REF _Ref336520009 \w \h 7 08D0C9EA79F9BACE118C8200AA004BA90B02000000080000000E0000005F005200650066003300330036003500320030003000300039000000  has been updated to harmonize the marking and documentation requirement within IEC 61800 (all parts);
h) existing  REF _Ref51162926 \w \h Annex A 08D0C9EA79F9BACE118C8200AA004BA90B02000000080000000D0000005F0052006500660035003100310036003200390032003

IEC 61800-5-3:2021, which is a product standard, specifies requirements and makes recommendations for the design and development, integration and validation of safety-related encoder (Encoder(SR)) in terms of their functional safety considerations, electrical safety and environmental conditions. It applies to Encoder(SR), being sensors as part of a PDS(SR). This document can also be referred to and used for Encoder(SR) in any other safety-related application, for example safety-related position monitoring.
This document is applicable where functional safety of an encoder is claimed and the Encoder(SR) is operating mainly in the high demand or continuous mode. The requirements of IEC 61800-5-2:2016 for PDS(SR) apply to Encoder(SR) as applicable.
This document includes additional or different requirements for Encoder(SR). It sets out safety-related considerations of Encoder(SR) in terms of the framework of IEC 61508 (all parts), and introduces requirements for Encoder(SR) as subsystems of a safety-related system. It is intended to facilitate the realisation of the electrical/electronic/programmable electronic (E/E/PE) and mechanical parts of an Encoder(SR) in relation to the safety performance of safety sub-function(s) of an Encoder(SR).

IEC 61800-1:2021 applies to adjustable speed electric DC power drive systems, which include semiconductor power conversion and the means for their control, protection, monitoring, measurement and the DC motors.
It applies to adjustable speed electric power drive systems intended to feed DC motors from a BDM/CDM connected to line-to-line voltages up to and including 1 kV AC 50 Hz or 60 Hz and/or voltages up to and including 1,5 kV DC input side.
NOTE 1 Adjustable speed electric AC power drive systems intended to feed AC motors are covered by
IEC 61800-2.
NOTE 2 This document can be used as a reference for adjustable speed electric power drive systems, intended to feed DC motors from a BDM/CDM connected to line-to-line voltages up to and including 1,5 kV AC, 50 Hz or 60 Hz and/or voltages up to and including 2,25 kV DC input side.
This edition includes the following significant technical changes with respect to the previous edition:
a) the clause structure has been harmonized with IEC 61800-2;
b) Clause 2 has been updated;
c) Clause 3 has been updated including fundamental definitions to be used across IEC 61800 (all parts);
d) Clause 4 has been updated with respect to:
1) description of the basic topology for BDM/CDM/PDS (4.2);
2) ratings and performance (4.3 and 4.4);
3) reference to applicable standards within the IEC 61800 series with respect to EMC (IEC 61800-3), general safety (IEC 61800-5-1), functional safety (IEC 61800-5-2), load duty aspects (IEC TR 61800-6), communication profiles (IEC 61800-7 series),power interface voltage (IEC TS 61800-8), and ecodesign energy efficiency standards (IEC 61800-9) to avoid conflicting requirements (4.5, 4.6, 4.7, 4.10, 4.11, 4.12);
4) update of requirement for ecodesign (4.8);
5) update of requirement for environmental evaluation (4.9);
6) implementation of requirement for explosive atmosphere (4.13);
e) Clause 5 has been updated with test requirement in order to provide a clear link between design requirement and test requirement;
f) Clause 6 has been updated to harmonize the marking and documentation requirement within IEC 61800 (all parts);
g) the Annexes have been updated.

IEC 61803:2020 is available as IEC 61803:2020 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.
IEC 61803:2020 applies to all line-commutated high-voltage direct current (HVDC) converter stations used for power exchange (power transmission or back-to-back installation) in utility systems. This document presumes the use of 12-pulse thyristor converters but can, with due care, also be used for 6-pulse thyristor converters. In some applications, synchronous compensators or static var compensators (SVC) may be connected to the AC bus of the HVDC converter station. The loss determination procedures for such equipment are not included in this document. This document presents a set of standard procedures for determining the total losses of an HVDC converter station. The procedures cover all parts, except as noted above, and address no-load operation and operating losses together with their methods of calculation which use, wherever possible, measured parameters. Converter station designs employing novel components or circuit configurations compared to the typical design assumed in this document, or designs equipped with unusual auxiliary circuits that could affect the losses, are assessed on their own merits. This edition includes the following significant technical changes with respect to the previous edition:
- to facilitate the application of this document and to ensure its quality remains consistent, 5.1.8 and 5.8 have been reviewed, taking into consideration that the present thyristor production technology provides considerably less thyristor parameters dispersion comparing with the situation in 1999 when the first edition of IEC 61803 was developed, and therefore the production records of thyristors can be used for the power losses calculation;
- the calculation of the total station load losses (cases D1 and D2 in Annex C) has been corrected.

IEC TR 60919-1:2020 is available as IEC TR 60919-1:2020 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.
IEC TR 60919-1:2020(E) provides general guidance on the steady-state performance requirements of high-voltage direct current (HVDC) systems. It concerns the steady-state performance of two-terminal HVDC systems utilizing 12-pulse converter units comprised of three-phase bridge (double-way) connections, but it does not cover multi­terminal HVDC transmission systems. Both terminals are assumed to use thyristor valves as the main semiconductor valves and to have power flow capability in both directions. Diode valves are not considered in this document. This edition includes the following significant technical changes with respect to the previous edition:
- Figure 8 and Figure 20 have been updated, a new Figure 18 "LCC/VSC hybrid bipolar system" has been added;
- the HVDC system control objectives have been supplemented;
- additional explanations regarding the HVDC system control structure have been given;
- a new subclause 13.6 on HVDC system protection has been added.

IEC 62823:2015 defines routine and type tests on thyristor valves used in thyristor controlled series capacitor (TCSC) installations for a.c. power transmission. The tests specified in this standard are based on air insulated valves operating in capacitive boost mode or bypass mode.

IEC TR 60146-1-2:2019 is available as IEC TR 60146-1-2:2019 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.
IEC TR 60146-1-2:2019 gives guidance on variations to the specifications given in IEC 60146-1-1:2009 to enable the specification to be extended in a controlled form for special cases. Background information is also given on technical points, which facilitates the use of IEC 60146-1-1:2009. This technical report primarily covers line commutated converters and is not in itself a specification, except as regards certain auxiliary components, in so far as existing standards may not provide the necessary data. This fifth edition includes the following significant technical changes with respect to the previous edition:
a) addition of annexes concerning the applications of converter transformers and of fuses for overcurrent protection;
b) changes of calculation methods related the inductive voltage regulation and changes of description on transformer losses to be consistent with the latest transformer standards;
c) addition and updates of references based on the latest information.

IEC TR 63262:2019(E) provides guidelines for applying unified power flow controllers (UPFC) in power systems. It includes letter symbols, terms and definitions, principles and configurations, design rules, performance requirements for key equipment control and protection, insulation co-ordination, system performance and tests. This technical report applies to the UPFC based on modular multi-level converter (MMC) technology, as well as UPFC based on three-level converter technology.

IEC 62751-2:2014 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 sources 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 "cascaded two-level converter"). The main formulae are given for the two-level "half-bridge" configuration but guidance is also given as to how to extend the results to certain other types of MMC building block configuration.

IEC TR 62757:2015(E), which is a technical report, deals with fire prevention measures on converters and their valve halls for high voltage direct current (HVDC) systems, static VAR compensators (SVC) and flexible AC transmission systems (FACTS). It is intended to be primarily for the use of the utilities and consultants who are responsible for issuing technical specifications for new converter valves and valve halls. It concerns fire incidents in HVDC projects using line commutated converters (LCC) or voltage sourced converter (VSC) technology and it is from these projects that most examples of fires and fire incidents are taken. This technical report also addresses converter valves and valve halls for SVC and FACTS. This technical report provides general recommendations to be considered while preparing specifications for these systems. Specific requirements for a particular project need to be clearly specified and mutually agreed upon between the supplier and the purchaser.

IEC 60633:2019 is available as IEC 60633:2019 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.
IEC 6033:2019 defines terms for high-voltage direct current (HVDC) power transmission systems and for HVDC substations using electronic power converters for the conversion from AC to DC or vice versa. This document is applicable to HVDC substations with line commutated converters, most commonly based on three-phase bridge (double way) connections (see Figure 2) in which unidirectional electronic valves, for example semiconductor valves, are used. For the thyristor valves, only the most important definitions are included in this document. A more comprehensive list of HVDC valve terminology is given in IEC 60700-2. This edition includes the following significant technical changes with respect to the previous edition:
- 40 terms and definitions have been amended and 31 new terms and definitions have been added mainly on converter units and valves, converter operating conditions, HVDC systems and substations and HVDC substation equipment;
- a new Figure 13 on capacitor commutated converter configurations has been added.
The contents of the corrigendum of February 2020 have been included in this copy.

IEC 62909-2:2019 specifies GCPC interface requirements for particular distributed energy resources, namely electric vehicle (EV), battery, and photovoltaic (PV) systems. These requirements are in addition to the general requirements given in IEC 62909-1.
This International Standard is to be used in conjunction with IEC 62909-1:2017.
The clauses of particular requirements in this document supplement or modify the corresponding clauses in IEC 62909-1:2017. Where the text of subsequent clauses indicates an "addition" to or a "replacement" of the relevant requirement, test specification or explanation of IEC 62909-1:2017, these changes are made to the relevant text of IEC 62909­1:2017. Where no change is necessary and the clause is applicable, the words "The provisions of IEC 62909-1:2017, Clause XX shall apply" are used. Additional clauses, tables, figures and notes which are not included in IEC 62909-1:2017, are numbered starting from 101.

IEC 62747:2014 defines terms for the subject of self-commutated voltage-sourced converters used for transmission of power by high voltage direct current (HVDC). The standard is written mainly for the case of application of insulated gate bipolar transistors (IGBTs) in voltage sourced converters (VSC) but may also be used for guidance in the event that other types of semiconductor devices which can both be turned on and turned off by control action are used. Line-commutated and current-sourced converters for high-voltage direct current (HVDC) power transmission systems are specifically excluded from this standard. The contents of the corrigendum of February 2015 have been included in this copy.

IEC 62477-2:2018 applies to power electronic converter systems (PECS) and equipment, their components for electronic power conversion and electronic power switching, including the means for their control, protection, monitoring and measurement, such as with the main purpose of converting electric power, with rated system voltages from 1 000 V AC or 1 500 V DC up to 36 kV AC or 54 kV DC.
This document can also be used as a reference standard for product committees producing product standards for adjustable speed electric power drive systems (PDS),
standalone uninterruptible power systems (UPS), and
stabilized DC power supplies.
For PECS for which no product standard exists, this document provides minimum requirements for safety aspects.  
This document has the status of a group safety publication in accordance with IEC Guide 104 for power electronic converter systems and equipment for solar, wind, tidal, wave, fuel cell or similar energy sources.
According to IEC Guide 104, one of the responsibilities of technical committees is, wherever applicable, to make use of basic safety publications and/or group safety publications in the preparation of their product standards.
This document establishes a common terminology for safety aspects relating to PECS and equipment,
establishes minimum requirements for the coordination of safety aspects of interrelated parts within a PECS,
establishes a common basis for minimum safety requirements for the PEC portion of products that contain PEC,
specifies requirements to reduce risks of fire, electric shock, thermal, energy and mechanical hazards, during use and operation and, where specifically stated, during service and maintenance,
specifies minimum requirements to reduce risks with respect to pluggable and permanently connected equipment, whether it consists of a system of interconnected units or independent units, subject to installing, operating and maintaining the equipment in the manner prescribed by the manufacturer,
establishes an arc fault rating label requirement with testing instructions for PEC and PECS, and
covers power electronic converters and systems in open type design, which are catalog (pre-defined commercially available) power electronic converters and systems or engineered solutions from same.
This document does not cover telecommunications apparatus other than power supplies to such apparatus,
functional safety aspects as covered by, for example, IEC 61508 (all parts),
electrical equipment and systems for railways applications and electric vehicles, and
power electronic converters and systems in open type design, which are – in their major part – dimensioned, designed and constructed according to the user’s individual requirements and specifications and follow power installation standards, for example IEC 61936-1.

Specifies end-to-end dimensions for given nominal sizes and pressure ratings of buttweld, two-way, global-type, straigth pattern control valves for nominal sizes DN 15 through DN 450. Aids users in their piping design by providing normalized dimensions of buttweld end control valves.

IEC 62751-1:2014 sets out the general principles for calculating the power losses in the converter valves of a voltage sourced converter (VSC) for high-voltage direct current (HVDC) applications, independent of the converter topology. Several clauses in the standard can also be used for calculating the power losses in the dynamic braking valves (where used) and as guidance for calculating the power losses of the valves for a STATCOM installation.

Specifies the content, format and recording method of the data blocks forming the helical records on the tape. Describes the common specifications for cassettes, modulation method, magnetization  and basic system data, for helical-scan digital video cassette recording system using 6,35 mm (1/4 inch) magnetic tape. Defines the electrical and mechanical characteristics of equipment which will provide for the interchangeability of recorded cassettes.

IEC 62927:2017 applies to self-commutated valves, for use in voltage sourced converter (VSC) for static synchronous compensator (STATCOM). It is restricted to electrical type and production tests.
The tests specified in this document are based on air insulated valves. For other types of valves, the test requirements and acceptance criteria are agreed between the purchaser and the supplier.
The contents of the corrigendum of December 2017 have been included in this copy.

IEC 62040-1:2017 applies to movable, stationary, fixed or built-in UPS for use in low-voltage distribution systems and that are intended to be installed in an area accessible by an ordinary person or in a restricted access area as applicable, that deliver fixed frequency AC output voltage with port voltages not exceeding 1 000 V AC or 1 500 V DC and that include an energy storage device. It applies to pluggable and to permanently connected UPS, whether consisting of a system of interconnected units or of independent units, subject to installing, operating and maintaining the UPS in the manner prescribed by the manufacturer.
This document specifies requirements to ensure safety for the ordinary person who comes into contact with the UPS and, where specifically stated, for the skilled person. The objective is to reduce risks of fire, electric shock, thermal, energy and mechanical hazards during use and operation and, where specifically stated, during service and maintenance.
This product standard is harmonized with the applicable parts of group safety publication IEC 62477-1:2012 for power electronic converter systems and contains additional requirements relevant to UPS.
This edition includes the following significant technical change with respect to the previous edition: the reference document has been changed from IEC 60950-1:2005 (safety for IT equipment) to IEC 62477-1 (group safety standard for power electronic converters).
The contents of the corrigendum of October 2019 have been included in this copy.

Specifies the character information system which is applicable to the whole recording system of the helical-scan digital video cassette using 6,35 mm magnetic tape. Provides the method of recording characters in many languages and moreover provides easy operation for users.

IEC 62909-1:2017 specifies general aspects of bi-directional grid-connected power converters (GCPC), consisting of a grid-side inverter with two or more types of DC-port interfaces on the application side with system voltages not exceeding 1 000 V AC or 1 500 V DC. In special cases, a GCPC will have only one DC-port interface, which is connected to a bidirectional energy-storage device. This document includes terminology, specifications, performance, safety, system architecture, and test-case definitions. The "system architecture" defines interaction between the inverter and converters. Requirements which are common, general, and independent of special characteristics of individual generators and bi-directional storages are defined.
This document does not cover uninterruptible power supply (UPS) systems, which fall under the scope of IEC 62040 (all parts). Requirements for internal and external digital communication might be necessary; the interface requirements including communication with distributed energy resources are provided in a future part of IEC 62909. All EMC requirements are defined by reference to existing IEC standards. External communication requirements are out of scope of this document.