IEHT - Electrotechnics - Hydraulic turbins

TAN - // IEC Corrigendum

2020-05-07: When amdt is published, add supersession link between PR=65214 and PR=21445

2020-05-07: When amdt is published, add supersession link between PR=64419 and PR=21139

This part of IEC 61400 specifies procedures for validation of electrical simulation models for
wind turbines and wind power plants, intended to be used in power system and grid stability
analyses. The validation procedures are based on the tests specified in IEC 61400-21 (all
parts). The validation procedures are applicable to the generic models specified in
IEC 61400-27-1 and to other fundamental frequency wind power plant models and wind
turbine models.
The validation procedures for wind turbine models focus on fault ride through capability and
control performance. The fault ride through capability includes response to balanced and
unbalanced voltage dips as well as voltage swells. The control performance includes active
power control, frequency control, synthetic inertia control and reactive power control. The
validation procedures for wind turbine models refer to the tests specified in IEC 61400-21-1.
The validation procedures for wind turbine models refer to the wind turbine terminals.
The validation procedures for wind power plant models is not specified in detail because
IEC 61400-21-2 which has the scope to specify tests of wind power plants is at an early
stage. The validation procedures for wind power plant models refer to the point of connection
of the wind power plant.
The validation procedures specified in IEC 61400-27-2 are based on comparisons between
measurements and simulations, but they are independent of the choice of software simulation
tool.

This part of IEC 61400 defines standard electrical simulation models for wind turbines and wind
power plants. The specified models are time domain positive sequence simulation models,
intended to be used in power system and grid stability analyses. The models are applicable for
dynamic simulations of short term stability in power systems.
This document defines the generic terms and parameters for the electrical simulation models.
This document specifies electrical simulation models for the generic wind power plant
topologies / configurations currently on the market. The wind power plant models include wind
turbines, wind power plant control and auxiliary equipment. The wind power plant models are
described in a modular way which can be applied for future wind power plant concepts and with
different wind turbine concepts.
This document specifies electrical simulation models for the generic wind turbine
topologies/concepts/configurations currently on the market. The purpose of the models is to
specify the electrical characteristics of a wind turbine at the wind turbine terminals. The wind
turbine models are described in a modular way which can be applied for future wind turbine
concepts. The specified wind turbine models can either be used in wind power plant models or
to represent wind turbines without wind power plant relationships.
The electrical simulation models specified in IEC 61400-27-1 are independent of any software
simulation tool.

This part of IEC 61400 specifies requirements to ensure the engineering integrity of wind
turbine blades as well as an appropriate level of operational safety throughout the design
lifetime. It includes requirements for:
• aerodynamic and structural design,
• material selection, evaluation and testing,
• manufacture (including associated quality management),
• transportation, installation, operation and maintenance of the blades.
The purpose of this document is to provide a technical reference for designers,
manufacturers, purchasers, operators, third party organizations and material suppliers, as
well as to define requirements for certification.
With respect to certification, this document provides the detailed basis for fulfilling the current
requirements of the IECRE system, as well as other IEC standards relevant to wind turbine
blades. When used for certification, the applicability of each portion of this document should
be determined based on the extent of certification, and associated certification modules per
the IECRE system.
The rotor blade is defined as all components integrated in the blade design, excluding
removable bolts in the blade root connection and support structures for installation.
This document is intended to be applied to rotor blades for all wind turbines. For rotor blades
used on small wind turbines according to IEC 61400-2, the requirements in that document are
applicable.
At the time this document was written, most blades were produced for horizontal axis wind
turbines. The blades were mostly made of fiber reinforced plastics. However, most principles
given in this document would be applicable to any rotor blade configuration, size and material.

The purpose of this this part of IEC 63132 is to establish, in a general way, suitable
procedures and tolerances for the installation of a vertical Kaplan or propeller turbine. This
document presents a typical assembly and whenever the word “turbine” is used in this
document, it refers to a vertical Kaplan or propeller turbine. There are many possible ways to
assemble a unit. The size of the machine, design of the machine, layout of the powerhouse or
delivery schedule of the components are some of the elements that could result in additional
steps, the elimination of some steps and/or assembly sequences.
It is understood that a publication of this type will be binding only if, and to the extent that,
both contracting parties have agreed upon it.
This document excludes matters of purely commercial interest, except those inextricably
bound up with the conduct of installation.
The tolerances in this document have been established upon best practices and experience,
although it is recognized that other standards specify different tolerances.
Wherever this document specifies that documents, drawings or information is supplied by a
manufacturer (or by manufacturers), each individual manufacturer will furnish the appropriate
information for their own supply only.

The purpose of this this part of IEC 63132 is to establish, in a general way, suitable procedures
and tolerances for the installation of a vertical Francis turbine or pump-turbine. This document
presents a typical assembly and whenever the word “turbine” is used in this document, it refers
to a vertical Francis turbine or a pump-turbine. There are many possible ways to assemble a
unit. The size of the machine, design of the machine, layout of the powerhouse or delivery
schedule of the components are some of the elements that could result in additional steps, the
elimination of some steps and/or assembly sequences.
It is understood that a publication of this type will be binding only if, and to the extent that, both
contracting parties have agreed upon it.
This document excludes matters of purely commercial interest, except those inextricably bound
up with the conduct of installation.
The tolerances in this document have been established upon best practices and experience,
although it is recognized that other standards specify different tolerances.
Wherever this document specifies that documents, drawings or information is supplied by a
manufacturer (or by manufacturers), each individual manufacturer will furnish the appropriate
information for their own supply only.

The purpose of this part of IEC 63132 is to establish, in a general way, suitable procedures and
tolerances for installation of generator. This document presents a typical assembly. There are
many possible ways to assemble a unit. The size of the machines, design of the machines,
layout of the powerhouse or delivery schedule of the components are some of the elements that
could result in additional steps, the elimination of some steps and/or assembly sequences.
It is understood that a publication of this type will be binding only if, and to the extent that, both
contracting parties have agreed upon it.
This document excludes matters of purely commercial interest, except those inextricably bound
up with the conduct of installation.
This document applies to vertical generators according to IEC 60034-7 1.
The tolerances in this document have been established upon best practices and experience,
although it is recognized that other standards specify different tolerances.
Brushless excitation system is not included in this document.
Wherever this document specifies that documents, drawings or information is supplied by a
manufacturer (or by manufacturers), each individual manufacturer will furnish the appropriate
information for their own supply only.

This part of IEC 61400 specifies requirements and general principles to be used in assessing
the structural integrity of onshore wind turbine support structures (including foundations). The
scope includes the geotechnical assessment of the soil for generic or site specific purposes.
The strength of any flange and connection system connected to the rotor nacelle assembly
(including connection to the yaw bearing) are designed and documented according to this
document or according to IEC 61400-1. The scope includes all life cycle issues that may affect
the structural integrity such as assembly and maintenance.
The assessment assumes that load data has been derived as defined in IEC 61400-1 or
IEC 61400-2 and using the implicit reliability level and partial safety factors for loads.

The purpose of this part of IEC 63132 is to establish, in a general way, suitable procedures and
tolerances for the installation of hydroelectric turbines and generators. This document presents
a typical assembly. There are many possible ways to assemble a unit. The size of the machines,
design of the machines, layout of the powerhouse and delivery schedule of the components are
some of the elements that could result in additional steps, the elimination of some steps and/or
assembly sequences.
It is understood that a publication of this type will be binding only if, and to the extent that, both
contracting parties have agreed upon it.
Installations for refurbishment projects or for small hydro projects are not in the scope of this
document. An agreement between all parties is necessary.
This document excludes matters of purely commercial interest, except those inextricably bound
up with the conduct of installation.
The tolerances in this document have been established upon best practices and experience,
although it is recognized that other standards specify different tolerances.
Wherever this document specifies that documents, drawings or information is supplied by a
manufacturer (or manufacturers), each individual manufacturer will furnish the appropriate
information for their own supply only.

2020-03-23: corrigendum created to confirm EN 61400-22:2011 and is not the result of a mistake (see BT decision D165/C016)

TAN - // IEC Corrigendum

This document presents measurement procedures that enable noise emissions of a wind turbine to be characterised. This involves using measurement methods appropriate to noise emission assessment at locations close to the machine, in order to avoid errors due to sound propagation, but far away enough to allow for the finite source size. The procedures described are different in some respects from those that would be adopted for noise assessment in community noise studies. They are intended to facilitate characterisation of wind turbine noise with respect to a range of wind speeds and directions. Standardisation of measurement procedures will also facilitate comparisons between different wind turbines. The procedures present methodologies that will enable the noise emissions of a single wind turbine to be characterised in a consistent and accurate manner. These procedures include the following: - location of acoustic measurement positions; - requirements for the acquisition of acoustic, meteorological, and associated wind turbine operational data; - analysis of the data obtained and the content for the data report; and - definition of specific acoustic emission parameters, and associated descriptors which are used for making environmental assessments. This International Standard is not restricted to wind turbines of a particular size or type. The procedures described in this standard allow for the thorough description of the noise emission from a wind turbine. A method for small wind turbines is described in Annex F.

This part of IEC 61400 deals with safety philosophy, quality assurance, and engineering
integrity and specifies requirements for the safety of small wind turbines (SWTs) including
design, installation, maintenance and operation under specified external conditions. Its
purpose is to provide the appropriate level of protection against damage from hazards from
these systems during their planned lifetime.
This standard is concerned with all subsystems of SWTs such as protection mechanisms,
internal electrical systems, mechanical systems, support structures, foundations and the
electrical interconnection with the load. A small wind turbine system includes the wind turbine
itself including support structures, the turbine controller, the charge controller / inverter (if
required), wiring and disconnects, the installation and operation manual(s) and other
documentation.
While this standard is similar to IEC 61400-1, it does simplify and make significant changes in
order to be applicable to small wind turbines. Any of the requirements of this standard may be
altered if it can be suitably demonstrated that the safety of the turbine system is not
compromised. This provision, however, does not apply to the classification and the associated
definitions of external conditions in Clause 6. Compliance with this standard does not relieve
any person, organisation, or corporation from the responsibility of observing other applicable
regulations.
This standard applies to wind turbines with a rotor swept area smaller than or equal to
200 m2, generating electricity at a voltage below 1 000 V a.c. or 1 500 V d.c. for both on-grid
and off-grid applications.
This standard should be used together with the appropriate IEC and ISO standards (see
Clause 2).

This part of IEC 61400 specifies essential design requirements to ensure the structural
integrity of wind turbines. Its purpose is to provide an appropriate level of protection against
damage from all hazards during the planned lifetime.
This document is concerned with all subsystems of wind turbines such as control and
protection functions, internal electrical systems, mechanical systems and support structures.
This document applies to wind turbines of all sizes. For small wind turbines, IEC 61400-2 can
be applied. IEC 61400-3-1 provides additional requirements to offshore wind turbine
installations.
This document is intended to be used together with the appropriate IEC and ISO standards
mentioned in Clause 2.

This document specifies additional requirements for assessment of the external conditions at an offshore wind turbine site and specifies essential design requirements to ensure the engineering integrity of fixed offshore wind turbines. Its purpose is to provide an appropriate level of protection against damage from all hazards during the planned lifetime. This document focuses on the engineering integrity of the structural components of an offshore wind turbine but is also concerned with subsystems such as control and protection mechanisms, internal electrical systems and mechanical systems. A wind turbine shall be considered as a fixed offshore wind turbine if the support structure is subject to hydrodynamic loading and it is founded on the seabed. The design requirements specified in this document are not sufficient to ensure the engineering integrity of floating offshore wind turbines. For floating installations, reference is made to IEC 61400-3-2. In the remainder of this document, the term “offshore wind turbine” is assumed to refer to those that are fixed to the seabed. This document should be used together with the appropriate IEC and ISO standards mentioned in Clause 2. In particular, this document is fully consistent with the requirements of IEC 61400-1. The safety level of the offshore wind turbine designed according to this document shall be at or exceed the level inherent in IEC 61400-1. In some clauses, where a comprehensive statement of requirements aids clarity, replication of text from IEC 61400-1 is included.

This Standard  applies to lightning protection of wind turbine generators and wind power systems. Refer to Annex M guidelines for small wind turbines. This document defines the lightning environment for wind turbines and risk assessment for wind turbines in that environment. It defines requirements for protection of blades, other structural components and electrical and control systems against both direct and indirect effects of lightning. Test methods to validate compliance are included. Guidance on the use of applicable lightning protection, industrial electrical and EMC standards including earthing is provided. Guidance regarding personal safety is provided. Guidelines for damage statistics and reporting are provided. Normative references are made to generic standards for lightning protection, low-voltage systems and high-voltage systems for machinery and installations and electromagnetic compatibility (EMC).

This part of IEC 61400 includes:
• definition and specification of the quantities to be determined for characterizing the
electrical characteristics of a grid-connected wind turbine;
• measurement procedures for quantifying the electrical characteristics;
• procedures for assessing compliance with electrical connection requirements, including
estimation of the power quality expected from the wind turbine type when deployed at a
specific site.
The measurement procedures are valid for single wind turbines with a three-phase grid
connection. The measurement procedures are valid for any size of wind turbine, though this
part of IEC 61400 only requires wind turbine types intended for connection to an electricity
supply network to be tested and characterized as specified in this part of IEC 61400.
The measured characteristics are valid for the specific configuration and operational mode of
the assessed wind turbine product platform. If a measured property is based on control
parameters and the behavior of the wind turbine can be changed for this property, it is stated
in the test report. Example: Grid protection, where the disconnect level is based on a
parameter and the test only verifies the proper functioning of the protection, not the specific
level.
The measurement procedures are designed to be as non-site-specific as possible, so that
electrical characteristics measured at for example a test site can be considered
representative for other sites.
This document is for the testing of wind turbines; all procedures, measurements and tests
related to wind power plants are covered by IEC 61400-21-2.
The procedures for assessing electrical characteristics are valid for wind turbines with the
connection to the PCC in power systems with stable grid frequency.
NOTE
For the purposes of this document, the following terms for system voltage apply:
– Low voltage (LV) refers to Un ≤ 1 kV;
– Medium voltage (MV) refers to 1 kV < Un ≤ 35 kV;
– High voltage (HV) refers to 35 kV < Un ≤ 220 kV;
– Extra high voltage (EHV) refers to Un > 220 kV.

This part of IEC 61400 defines an information model from which time-based, and productionbased
availability indicators for services can be derived and reported.
The purpose is to provide standardised metrics that can be used to create and organise
methods for availability calculation and reporting according to the user’s needs.
The document provides information categories, which unambiguously describe how data is
used to characterise and categorise the operation. The information model specifies category
priority for discrimination between possible concurrent categories. Further, the model defines
entry and exit criteria to allocate fractions of time and production values to the proper
information category. A full overview of all information categories, exit and entry criteria is
given in Annex A, see Figure A.1.
The document can be applied to any number of WTGSs, whether represented by an individual
turbine, a fleet of wind turbines, a wind power station or a portfolio of wind power stations. A
wind power station is typically made up of all WTGSs, functional services and balance of plant
elements as seen from the point of common coupling.
Examples are provided in informative annexes which provide guidelines for calculation of
availability indicators:
• examples of optional information categories, Annex B;
• examples of application of the information categories for determination of availability,
Annex C;
• examples of application scenarios, Annex D;
• examples on methods for determination of potential production, Annex E;
• examples of how to expand the model to balance of plant elements, Annex F.
This document does not prescribe how availability indicators shall be calculated. The standard
does not specify the method of information acquisition, how to estimate the production terms
or to form the basis for power curve performance measurements – which is the objective of
IEC 61400-12.
A degree of uncertainty is inherent in both the measurement of a power curve and the
calculation of potential energy production. The stakeholders should agree upon acceptable
uncertainty parameters.

This document applies to laboratory models of any type of impulse or reaction hydraulic turbine,
storage pump or pump-turbine.
This document applies to models of prototype machines either with unit power greater than
5 MW or with reference diameter greater than 3 m. Full application of the procedures herein
prescribed is not generally justified for machines with smaller power and size. Nevertheless,
this document may be used for such machines by agreement between the purchaser and the
supplier.
In this document, the term "turbine" includes a pump-turbine operating as a turbine and the
term "pump" includes a pump-turbine operating as a pump.
This document excludes all matters of purely commercial interest, except those inextricably
bound up with the conduct of the tests.
This document is concerned with neither the structural details of the machines nor the
mechanical properties of their components, so long as these do not affect model performance
or the relationship between model and prototype performances.
This document covers the arrangements for model acceptance tests to be performed on
hydraulic turbines, storage pumps and pump-turbines to determine if the main hydraulic
performance contract guarantees (see 4.2) have been satisfied.
It contains the rules governing test conduct and prescribes measures to be taken if any phase
of the tests is disputed.
The main objectives of this document are:
– to define the terms and quantities used;
– to specify methods of testing and of measuring the quantities involved, in order to ascertain
the hydraulic performance of the model;
– to specify the methods of computation of results and of comparison with guarantees;
– to determine if the contract guarantees that fall within the scope of this document have been
fulfilled;
– to define the extent, content and structure of the final report.
The guarantees can be given in one of the following ways:
– guarantees for prototype hydraulic performance, computed from model test results
considering scale effects;
– guarantees for model hydraulic performance.
Moreover, additional performance data (see 4.4) can be needed for the design or the operation
of the prototype of the hydraulic machine. Contrary to the requirements of Clauses 4 to 6 related
to main hydraulic performance, the information of these additional data given in Clause 7 is
considered only as recommendation or guidance to the user (see 7.1).
It is particularly recommended that model acceptance tests be performed if the expected field
conditions for acceptance tests (see IEC 60041:1991) would not allow the verification of
guarantees given for the prototype machine.
A transposition method taking into account the model and prototype wall surface roughness for
the performance conversion on pump-turbines, Francis turbines, and axial machines is
described in IEC 62097. This method requires model and prototype surface roughness data and
is takes into account the shift in nED, QED and PED factors for determining the transposition of
efficiency between model and prototype. However, in the case of Francis machines with semispiral
casing and axial machines, the transposition method has not been fully validated due to
a lack of data. In addition, IEC 62097 does not apply to storage pumps, Pelton turbines, and
Dériaz. Therefore, for these and otherwise specifically agreed upon cases where hydraulically
smooth flow conditions are assumed on the model and the prototype, the transposition formula
and procedure given in Annex D and Annex I can be applied. Applications and limitations of
both this document and IEC 62097 transposition methods are discussed in Annex E.
The method for performance conversion from model to prototype needs to be clearly defined in
the main hydraulic performance contract.

This International Standard establishes the prototype hydraulic machine efficiency from model
test results, with consideration of scale effect including the effect of surface roughness.
This document is intended to be used for the assessment of the results of contractual model
tests of hydraulic machines.

This part of IEC 61400 specifies essential design requirements to ensure the structural
integrity of wind turbines. Its purpose is to provide an appropriate level of protection against
damage from all hazards during the planned lifetime.
This document is concerned with all subsystems of wind turbines such as control and
protection functions, internal electrical systems, mechanical systems and support structures.
This document applies to wind turbines of all sizes. For small wind turbines, IEC 61400-2 can
be applied. IEC 61400-3-1 provides additional requirements to offshore wind turbine
installations.
This document is intended to be used together with the appropriate IEC and ISO standards
mentioned in Clause 2.

This document gives guidelines for:
a) presenting data on hydro-abrasive erosion rates on several combinations of water quality, operating conditions, component materials, and component properties collected from a variety of hydro sites;
b) developing guidelines for the methods of minimizing hydro-abrasive erosion by modifications to hydraulic design for clean water. These guidelines do not include details such as hydraulic profile shapes which are determined by the hydraulic design experts for a given site;
c) developing guidelines based on “experience data” concerning the relative resistance of materials faced with hydro-abrasive erosion problems;
d) developing guidelines concerning the maintainability of materials with high resistance to hydro-abrasive erosion and hardcoatings;
e) developing guidelines on a recommended approach, which owners could and should take to ensure that specifications communicate the need for particular attention to this aspect of hydraulic design at their sites without establishing criteria which cannot be satisfied because the means are beyond the control of the manufacturers;
f) developing guidelines concerning operation mode of the hydro turbines in water with particle materials to increase the operation life.
It is assumed in this document that the water is not chemically aggressive. Since chemical aggressiveness is dependent upon so many possible chemical compositions, and the materials of the machine, it is beyond the scope of this document to address these issues.
It is assumed in this document that cavitation is not present in the turbine. Cavitation and hydro-abrasive erosion can reinforce each other so that the resulting erosion is larger than the sum of cavitation erosion plus hydro-abrasive erosion. The quantitative relationship of the resulting hydro-abrasive erosion is not known and it is beyond the scope of this document to assess it, except to suggest that special efforts be made in the turbine design phase to minimize cavitation.
Large solids (e.g. stones, wood, ice, metal objects, etc.) traveling with the water can impact turbine components and produce damage. This damage can in turn increase the flow turbulence thereby accelerating wear by both cavitation and hydro-abrasive erosion. Hydroabrasive erosion resistant coatings can also be damaged locally by impact of large solids. It isbeyond the scope of this document  to address these issues.
This document focuses mainly on hydroelectric powerplant equipment. Certain portions can
also be applicable to other hydraulic machines.

This document presents measurement procedures that enable noise emissions of a wind turbine to be characterised. This involves using measurement methods appropriate to noise emission assessment at locations close to the machine, in order to avoid errors due to sound propagation, but far away enough to allow for the finite source size. The procedures described are different in some respects from those that would be adopted for noise assessment in community noise studies. They are intended to facilitate characterisation of wind turbine noise with respect to a range of wind speeds and directions. Standardisation of measurement procedures will also facilitate comparisons between different wind turbines. The procedures present methodologies that will enable the noise emissions of a single wind turbine to be characterised in a consistent and accurate manner. These procedures include the following: - location of acoustic measurement positions; - requirements for the acquisition of acoustic, meteorological, and associated wind turbine operational data; - analysis of the data obtained and the content for the data report; and - definition of specific acoustic emission parameters, and associated descriptors which are used for making environmental assessments. This International Standard is not restricted to wind turbines of a particular size or type. The procedures described in this standard allow for the thorough description of the noise emission from a wind turbine. A method for small wind turbines is described in Annex F.

This part of IEC 61400-25 specifies standard techniques for testing of compliance of
implementations, as well as specific measurement techniques to be applied when declaring
performance parameters. The use of these techniques will enhance the ability of users to
purchase systems that integrate easily, operate correctly, and support the applications as
intended.
This part of IEC 61400-25 defines:
• the methods and abstract test cases for compliance testing of server and client devices
used in wind power plants,
• the metrics to be measured in said devices according to the communication requirements
specified in IEC 61400-25 (all parts).
NOTE The role of the test facilities for compliance testing and certifying the results are outside of the scope of
IEC 61400-25-5.

The focus of IEC 61400-25 (all parts) is on the communications between wind power plant
components such as wind turbines and actors such as SCADA systems. Internal
communication within wind power plant components is beyond the scope of
IEC 6140025
(all parts).
IEC 61400-25 (all parts) is designed for a communication environment supported by a clientserver
model. Three areas are defined, that are modelled separately to ensure the scalability
of implementations:
1) wind power plant information models,
2) information exchange model, and
3) mapping of these two models to a standard communication profile.
The wind power plant information model and the information exchange model, viewed
together, constitute an interface between client and server. In this conjunction, the wind
power plant information model serves as an interpretation frame for accessible wind power
plant data. The wind power plant information model is used by the server to offer the client a
uniform, component-oriented view of the wind power plant data. The information exchange
model reflects the whole active functionality of the server. IEC 61400-25 (all parts) enables
connectivity between a heterogeneous combination of client and servers from different
manufacturers and suppliers.
As depicted in Figure 1, IEC 61400-25 (all parts) defines a server with the following aspects:
– information provided by a wind power plant component, for example, ‘wind turbine rotor
speed’ or ‘total power production of a certain time interval’ is modelled and made available
for access. The information modelled in IEC 61400-25 (all parts) is defined in
IEC 61400252
and IEC 61400-25-6,
– services to exchange values of the modelled information defined in IEC 61400-25-3,
– mapping to a communication profile, providing a protocol stack to carry the exchanged
values from the modelled information (IEC 61400-25-4).
IEC 61400-25 (all parts) only defines how to model the information, information exchange and
mapping to specific communication protocols. IEC 61400-25 (all parts) excludes a definition of
how and where to implement the communication interface, the application program interface
and implementation recommendations. However, the objective of IEC 6140025
(all parts) is
that the information associated with a single wind power plant component (such as a wind
turbine) is accessible through a corresponding logical device.
This part of IEC 61400-25 gives an overall description of the principles and models used in
IEC 6140025
(all parts).
NOTE IEC 61400-25 (all parts) focuses on the common, non-vendor-specific information. Those information items
that tend to vary greatly between vendor-specific implementations can for example be specified in bilateral
agreements, in user groups, or in amendments to IEC 61400-25 (all parts).

2021-04-13 FM: BT approved request to permanently remove link to LVD
2018-10-23 PeC: Citation under the LVD is pending on EN 62838:2016, which cannot be cited at the moment

This part of IEC 61400 provides a framework from which production-based performance
indicators of a WTGS (wind turbine generator system) can be derived. It unambiguously
describes how data is categorised and provides examples of how the data can be used to
derive performance indicators.
The approach of this part of IEC 61400 is to expand the time allocation model, introduced in
IEC TS 61400-26-1, with two additional layers for recording of the actual energy production
and potential energy production associated with the concurrent time allocation.
It is not the intention of this Technical Specification to define how production-based
availability shall be calculated. Nor is it the intention to form the basis for power curve
performance measurements, which is the objective of IEC 61400-12.
This document also includes informative annexes with:
• examples of determination of lost production,
• examples of algorithms for production-based indicators,
• examples of other performance indicators,
• examples of application scenarios.

This part of IEC 61400, which is a technical specification, provides a framework from which
time-based and production-based availability indicators of a wind power station can be
derived. It unambiguously describes how data is categorised and provides examples of how
the data can be used to derive availability indicators.
The approach is to apply the terms and definitions for the applied information models
introduced in IEC TS 61400-26-1 and IEC TS 61400-26-2 to a wind power station.
The basic approach is based on the assumption that a wind power station may be modelled
as one 'WTGS' representing a complete wind power station. The wind power station is made
up of all WTGSs, functional services and balance of plant elements as seen from the point of
common coupling.
It is not the intention of this specification to define how time-based and production-based
availability shall be calculated. Nor is it the intention to form the basis for power curve
performance measurements – which is the objective of IEC 61400-12. However, the annexes
should be regarded as examples and guidelines for developing methods for calculation of
availability indicators.
This document also includes informative annexes with:
• examples of how to expand the model to more services,
• examples of how to determine the information category for the wind power station,
• examples of how to expand the model to balance of plant elements,
• examples of determination of lost production,
• examples of availability algorithms for production based indicators,
• examples of other availability indicators,
• examples of application scenarios.

This document covers turbines, storage pumps and pump-turbines of all sizes and of the
following types:
• Francis;
• Kaplan;
• propeller;
• Pelton (turbines only);
• bulb turbines.
This document also identifies without detailed discussion, other powerhouse equipment that
could affect or be affected by a turbine, storage pump, or pump-turbine rehabilitation.
The object of this document is to assist in identifying, evaluating and executing rehabilitation
and performance improvement projects for hydraulic turbines, storage pumps and pumpturbines.
This document can be used by owners, consultants, and suppliers to define:
• needs and economics for rehabilitation and performance improvement;
• scope of work;
• specifications;
• evaluation of results.
This document is intended to be:
• an aid in the decision process;
• an extensive source of information on rehabilitation;
• an identification of the key milestones in the rehabilitation process;
• an identification of the points to be addressed in the decision processes.
This document is not intended to be a detailed engineering manual nor a maintenance
document.

This part of IEC 61400 gives guidelines for declaring the apparent sound power level and
tonality of a batch of wind turbines. The measurement procedures for apparent sound power
level and tonality are defined in IEC 61400-11.

This part of IEC 61400 defines generic information categories to which fractions of time can
be assigned for a wind turbine generating system (WTGS) considering internal and external
conditions based on fraction of time and specifying the following:
• generic information categories of a WTGS considering availability and other performance
indicators;
• information category priority in order to discriminate between concurrent categories;
• entry and exit point for each information category in order to allocate designation of time
• informative annexes including:
– examples of optional information categories,
– examples of algorithms for reporting availability and performance indicators,
– examples of application scenarios.

This part of IEC 61400 specifies a procedure for measuring the power performance
characteristics of a single wind turbine and applies to the testing of wind turbines of all types
and sizes connected to the electrical power network. In addition, this standard describes a
procedure to be used to determine the power performance characteristics of small wind
turbines (as defined in IEC 61400-2) when connected to either the electric power network or a
battery bank. The procedure can be used for performance evaluation of specific wind turbines
at specific locations, but equally the methodology can be used to make generic comparisons
between different wind turbine models or different wind turbine settings when site-specific
conditions and data filtering influences are taken into account.
The wind turbine power performance characteristics are determined by the measured power
curve and the estimated annual energy production (AEP). The measured power curve, defined
as the relationship between the wind speed and the wind turbine power output, is determined
by collecting simultaneous measurements of meteorological variables (including wind speed),
as well as wind turbine signals (including power output) at the test site for a period that is long
enough to establish a statistically significant database over a range of wind speeds and under
varying wind and atmospheric conditions. The AEP is calculated by applying the measured
power curve to reference wind speed frequency distributions, assuming 100 % availability.
This document describes a measurement methodology that requires the measured power
curve and derived energy production figures to be supplemented by an assessment of
uncertainty sources and their combined effects.

This part of IEC 61400-25 specifies the information models related to condition monitoring for
wind power plants and the information exchange of data values related to these models.
NOTE Conformance to IEC 61400-25-6 presupposes in principle conformance to IEC 61400-25-2, IEC 61400-25-3
and IEC 61400-25-4.
Figure 2 illustrates the information flow of a system using condition monitoring to perform
condition based maintenance. The figure illustrates how data values are refined and
concentrated through the information flow, ending up with the ultimate goal of condition based
maintenance; actions to be performed via issuing work orders to maintenance teams in order
to prevent the wind power plant device to stop providing its intended service.

IEC 61400-25-4:2008(E) specifies the specific mappings to protocol stacks encoding the messages required for the information exchange between a client and a remote server for data access and retrieval, device control, event reporting and logging, publisher/subscriber, self-description of devices (device data dictionary), data typing and discovery of data types. Covers several mappings, one of which shall be selected in order to be compliant with this part of IEC 61400-25. The IEC 61400-25 series is designed for a communication environment supported by a client-server model. Three areas are defined, that are modelled separately to ensure the scalability of implementations: wind power plant information model, information exchange model, and mapping of these two models to a standard communication profile.
This publication is of high relevance for Smart Grid.

IEC Corrigendum

This part of the IEC 61400 describes the measurement of fundamental structural loads on
wind turbines for the purpose of the load simulation model validation. The standard prescribes
the requirements and recommendations for site selection, signal selection, data acquisition,
calibration, data verification, measurement load cases, capture matrix, post-processing,
uncertainty determination and reporting. Informative annexes are also provided to improve
understanding of testing methods.
The methods described in this document can also be used for mechanical loads
measurements for other purposes such as obtaining a measured statistical representation of
loads, direct measurements of the design loads, safety and function testing, or measurement
of component loads. If these methods are used for an alternative objective or used for an
unconventional wind turbine design, the required signals, measurement load cases, capture
matrix, and post processing methods should be evaluated and if needed adjusted to fit the
objective.
These methods are intended for onshore electricity-generating, horizontal-axis wind turbines
(HAWTs) with rotor swept areas of larger than 200 m2. However, the methods described may
be applicable to other wind turbines (for example, small wind turbines, ducted wind turbines,
vertical axis wind turbines).

The focus of the IEC 61400-25 series is on the communications between wind power plant
components such as wind turbines and actors such as SCADA systems. Internal
communication within wind power plant components is outside the scope of the IEC 61400-25
series.
The IEC 61400-25 series is designed for a communication environment supported by a clientserver
model. Three areas are defined, that are modelled separately to ensure the scalability
of implementations:
1) wind power plant information models,
2) information exchange model, and
3) mapping of these two models to a standard communication profile.
The wind power plant information model and the information exchange model, viewed
together, constitute an interface between client and server. In this conjunction, the wind power
plant information model serves as an interpretation frame for accessible wind power plant
data. The wind power plant information model is used by the server to offer the client a
uniform, component-oriented view of the wind power plant data. The information exchange
model reflects the whole active functionality of the server. The IEC 61400-25 series enables
connectivity between a heterogeneous combination of client and servers from different
manufacturers and suppliers.
As depicted in Figure 1, the IEC 61400-25 series defines a server with the following aspects:
– information provided by a wind power plant component, for example “wind turbine rotor
speed” or “total power production of a certain time interval”, is modelled and made
available for access;
– services to exchange values of the modelled information defined in IEC 61400-25-3;
– mapping to a communication profile, providing a protocol stack, to carry the exchanged
values from the modelled information (IEC 61400-25-4).
The IEC 61400-25 series only defines how to model the information, information exchange
and mapping to specific communication protocols. The standard excludes a definition of how
and where to implement the communication interface, the application program interface and
implementation recommendations. However, the objective of the standard is that the
information associated with a single wind power plant component (such as a wind turbine) is
accessible through a corresponding logical device.
IEC 61400-25-2 specifies the information model of devices and functions related to wind
power plant applications. In particular, it specifies the compatible logical node names, and
data names for communication between wind power plant components. This includes the
relationship between logical devices, logical nodes and data. The names defined in the
IEC 61400-25 series are used to build the hierarchical object references applied for
communicating with components in wind power plants.
This part of IEC 61400-25 specifies common attribute types and common data classes related
to wind turbine applications. In particular it specifies common data classes for:
• setpoint value,
• status value,
• alarm,
• command,
• event counting,
• state timing,
• alarm set status.
Devices implementing the information model of this part choose one or more logical nodes as
required by the application.
NOTE 1 The IEC 61400-25 series focuses on the common, non-vendor-specific information. Those information
items that tend to vary greatly between vendor-specific implementations can for example be specified in bilateral
agreements or by user groups.
NOTE 2 This part does not provide tutorial material.

The focus of the IEC 61400-25 series is on the communications between wind power plant components such as wind turbines and actors such as SCADA systems. Internal communication within wind power plant components is outside the scope of the IEC 61400-25 series.
The IEC 61400-25 series is designed for a communication environment supported by a clientserver model. Three areas are defined, that are modelled separately to ensure the scalability of implementations: (1) wind power plant information models, (2) information exchange model, and (3) mapping of these two models to a standard communication profile. The wind power plant information model and the information exchange model, viewed together, constitute an interface between client and server. In this conjunction, the wind power plant information model serves as an interpretation frame for accessible wind power plant data. The wind power plant information model is used by the server to offer the client a uniform, component-oriented view of the wind power plant data. The information exchange model reflects the whole active functionality of the server. The IEC 61400-25 series enables connectivity between a heterogeneous combination of client and servers from different manufacturers and suppliers.
As depicted in Figure 1, the IEC 61400-25 series defines a server with the following aspects:
– information provided by a wind power plant component, e. g., “wind turbine rotor speed” or “total power production of a certain time interval” is modelled and made available for access. The information modelled in the IEC 61400-25 series is defined in IEC 61400-25-2;
– services to exchange values of the modelled information defined in IEC 61400-25-3;
– mapping to a communication profile, providing a protocol stack to carry the exchanged values from the modelled information (IEC 61400-25-4).
The IEC 61400-25 series only defines how to model the information, information exchange and mapping to specific communication protocols. The IEC 61400-25 series excludes a definition of how and where to implement the communication interface, the application program interface and implementation recommendations. However, the objective of the IEC 61400-25 series is that the information associated with a single wind power plant component (such as a wind turbine) is accessible through a corresponding logical device.
This part of IEC 61400-25 specifies an abstract communication service interface describing the information exchange between a client and a server for:
– data access and retrieval,
– device control,
– event reporting and logging,
– self-description of devices (device data dictionary),
– data typing and discovery of data types.

IEC 61400-27 defines standard electrical simulation models for wind turbines and wind power
plants. The specified models are time domain positive sequence simulation models, intended
to be used in power system and grid stability analyses. The models are applicable for dynamic
simulations of short term stability in power systems. IEC 61400-27 includes procedures for
validation of the specified electrical simulation models. The validation procedure for
IEC 61400-27 is based on tests specified in IEC 61400-21.
IEC 61400-27 consists of two parts with the following scope:
– IEC 61400-27-1 specifies dynamic simulation models for generic wind turbine topologies/
concepts / configurations on the market. IEC 61400-27-1 defines the generic terms and
parameters with the purpose of specifying the electrical characteristics of a wind turbine at
the connection terminals. The models are described in a modular way which can be
applied for future wind turbine concepts. The dynamic simulation models refer to the wind
turbine terminals. The validation procedure specified in IEC 61400-27-1 focuses on the
IEC 61400-21 tests for response to voltage dips, reference point changes and grid
protection.
– IEC 61400-27-2 specifies dynamic simulation models for the generic wind power plant
topologies / configurations on the market including wind power plant control and auxiliary
equipment. In addition IEC 61400-27-2 specifies a method to create models for future wind
power plant configurations. The wind power plant models are based on the wind turbine
models specified in IEC 61400-27-1.
The electrical simulation models specified in IEC 61400-27 are independent of any software
simulation tool.

This part of IEC 61400 deals with safety philosophy, quality assurance, and engineering
integrity and specifies requirements for the safety of small wind turbines (SWTs) including
design, installation, maintenance and operation under specified external conditions. Its
purpose is to provide the appropriate level of protection against damage from hazards from
these systems during their planned lifetime.
This standard is concerned with all subsystems of SWTs such as protection mechanisms,
internal electrical systems, mechanical systems, support structures, foundations and the
electrical interconnection with the load. A small wind turbine system includes the wind turbine
itself including support structures, the turbine controller, the charge controller / inverter (if
required), wiring and disconnects, the installation and operation manual(s) and other
documentation.
While this standard is similar to IEC 61400-1, it does simplify and make significant changes in
order to be applicable to small wind turbines. Any of the requirements of this standard may be
altered if it can be suitably demonstrated that the safety of the turbine system is not
compromised. This provision, however, does not apply to the classification and the associated
definitions of external conditions in Clause 6. Compliance with this standard does not relieve
any person, organisation, or corporation from the responsibility of observing other applicable
regulations.
This standard applies to wind turbines with a rotor swept area smaller than or equal to
200 m2, generating electricity at a voltage below 1 000 V a.c. or 1 500 V d.c. for both on-grid
and off-grid applications.
This standard should be used together with the appropriate IEC and ISO standards (see
Clause 2).

EN IEC 61400-23 defines the requirements for full-scale structural testing of wind turbine blades and for the interpretation and evaluation of achieved test results. The standard focuses on aspects of testing related to an evaluation of the integrity of the blade, for use by manufacturers and third party investigators. The following tests are considered in this standard: - static load tests; - fatigue tests; - static load tests after fatigue tests; - tests determining other blade properties. The purpose of the tests is to confirm to an acceptable level of probability that the whole population of a blade type fulfils the design assumptions. It is assumed that the data required to define the parameters of the tests are available and based on the standard for design requirements for wind turbines such as IEC 61400-1 or equivalent. Design loads and blade material data are considered starting points for establishing and evaluating the test loads. The evaluation of the design loads with respect to the actual loads on the wind turbines is outside the scope of this standard. At the time this standard was written, full-scale tests were carried out on blades of horizontal axis wind turbines. The blades were mostly made of fibre reinforced plastics and wood/epoxy. However, most principles would be applicable to any wind turbine configuration, size and material.

This Guide serves to:
a) present data on particle abrasion rates on several combinations of water quality, operating conditions, component materials, and component properties collected from a variety of hydro sites;
b) develop guidelines for the methods of minimizing particle abrasion by modifications to hydraulic design for clean water. These guidelines do not include details such as hydraulic profile shapes which should be determined by the hydraulic design experts for a given site;
c) develop guidelines based on “experience data” concerning the relative resistance of materials faced with particle abrasion problems;
d) develop guidelines concerning the maintainability of abrasion resistant materials and hard facing coatings;
e) develop guidelines on a recommended approach, which owners could and should take to ensure that specifications communicate the need for particular attention to this aspect of hydraulic design at their sites without establishing criteria which cannot be satisfied because the means are beyond the control of the manufacturers;
f) develop guidelines concerning operation mode of the hydro turbines in water with particle materials to increase the operation life; It is assumed in this Guide that the water is not chemically aggressive. Since chemical
aggressiveness is dependent upon so many possible chemical compositions, and the materials of the machine, it is beyond the scope of this Guide to address these issues. It is assumed in this Guide that cavitation is not present in the turbine. Cavitation and abrasion may reinforce each other so that the resulting erosion is larger than the sum of cavitation erosion plus abrasion erosion. The quantitative relationship of the resulting
abrasion is not known and it is beyond the scope of this guide to assess it, except to recommend that special efforts be made in the turbine design phase to minimize cavitation. Large solids (e.g. stones, wood, ice, metal objects, etc.) traveling with the water may impact turbine components and produce damage. This damage may in turn increase the flow turbulence thereby accelerating wear by both cavitation and abrasion. Abrasion resistant coatings can also be damaged locally by impact of large solids. It is beyond the scope of this Guide to address these issues. This guide focuses mainly on hydroelectric powerplant equipment. Certain portions may also be applicable to other hydraulic machines.

This part of IEC 61400-12 specifies a procedure for verifying the power performance characteristics of a single electricity-producing, horizontal axis wind turbine, which is not considered to be a small wind turbine per IEC 61400-2. It is expected that this standard will be used when the specific operational or contractual specifications may not comply with the
requirements set forth in IEC 61400-12-1:2005. The procedure can be used for power performance evaluation of specific turbines at specific locations, but equally the methodology can be used to make generic comparisons between different turbine models or different turbine settings.
The wind turbine power performance characterised by the measured power curve and the estimated AEP based on nacelle-measured wind speed will be affected by the turbine rotor (i.e. speeded up or slowed down wind speed). The nacelle-measured wind speed shall be corrected for this flow distortion effect. Procedures for determining that correction will be included in the methodology. In IEC 61400-12-1:2005, an anemometer is located on a meteorological tower that is located between two and four rotor diameters upwind of the test turbine. This location allows direct measurement of the ‘free’ wind with minimum interference from the test turbine’s rotor. In this IEC 61400-12-2 procedure, the anemometer is located on or near the test turbine’s nacelle. In this location, the anemometer is measuring wind speed that is strongly affected by the test turbine’s rotor and the nacelle. This procedure includes methods for determining and applying appropriate corrections for this interference. However, it should be noted that these corrections inherently increase the measurement uncertainty compared to a properly-configured test conducted in accordance with IEC 61400-12-1:2005. This IEC 61400-12-2 standard describes how to characterise a wind turbine’s power performance in terms of a measured power curve and the estimated AEP. The measured power curve is determined by collecting simultaneous measurements of nacelle-measured wind speed and power output for a period that is long enough to establish a statistically significant database over a range of wind speeds and under varying wind and atmospheric
conditions. In order to accurately measure the power curve, the nacelle-measured wind speed is adjusted using a transfer function to estimate the free stream wind speed. The procedure to measure and validate such a transfer function is presented herein. The AEP is calculated by applying the measured power curve to the reference wind speed frequency distributions, assuming 100 % availability. The procedure also provides guidance on determination of measurement uncertainty including assessment of uncertainty sources and recommendations for combining them into uncertainties in reported power and AEP.

This part of the IEC 61400 series is applicable to enclosed speed increasing gearboxes for horizontal axis wind turbine drivetrains with a power rating in excess of 500 kW. This standard applies to wind turbines installed onshore or offshore. This International Standard provides guidance on the analysis of the wind turbine loads in relation to the design of the gear and gearbox elements. The gearing elements covered by this standard include such gears as spur, helical or double helical and their combinations in parallel and epicyclic arrangements in the main power path. This standard does not apply to power take off gears (PTO). The standard is based on gearbox designs using rolling element bearings. Use of plain bearings is permissible under this standard, but the use and rating of them is not covered. Also included is guidance on the engineering of shafts, shaft hub interfaces, bearings and the gear case structure in the development of a fully integrated design that meets the rigours of the operating conditions. Lubrication of the transmission is covered along with prototype and production testing. Finally, guidance is provided on the operation and maintenance of the gearbox.

This part of IEC 61400 presents measurement procedures that enable noise emissions of a wind turbine to be characterised. This involves using measurement methods appropriate to noise emission assessment at locations close to the machine, in order to avoid errors due to sound propagation, but far away enough to allow for the finite source size. The procedures described are different in some respects from those that would be adopted for noise assessment in community noise studies. They are intended to facilitate characterisation of wind turbine noise with respect to a range of wind speeds and directions. Standardisation of measurement procedures will also facilitate comparisons between different wind turbines. The procedures present methodologies that will enable the noise emissions of a single wind turbine to be characterised in a consistent and accurate manner. These procedures include the following:
• location of acoustic measurement positions;
• requirements for the acquisition of acoustic, meteorological, and associated wind turbine operational data;
• analysis of the data obtained and the content for the data report; and
• definition of specific acoustic emission parameters, and associated descriptors which are used for making environmental assessments.
This International Standard is not restricted to wind turbines of a particular size or type. The procedures described in this standard allow for the thorough description of the noise emission from a wind turbine. A method for small wind turbines is described in Annex F.