WIND TURBINE GENERATOR SYSTEMS

88(Schwarz)01r04_2001-08-15 – Personal draft for 61400-25 WD � IEC:2001 – 1 –

Version 88(Schwarz)01r04_2001-08-15 – 15 August 2001Draft for IEC TC 88 WG 25 internal comments only.

Personal draft for: WD IEC 61400-25

WIND TURBINE GENERATOR SYSTEMSPart 25: Communications for monitoring and control of wind power

plants

This personal draft of the first official working document (WD) is forthe review by the members of IEC TC 88 WG 25 and for discussion at

the next meeting 5./6. September 2001 only

Version: 88(Schwarz)01r04_2001-08-15 – 15 August 2001



FOREWORD TO VERSION 88(Schwarz)01r04_2001-08-15

dated 15 August 2001

This foreword gives an overview of the major modifications that have been included in revi-sion 88(Schwarz)01r04_2001-08-15, for easier navigation:

1. This is the initial version of the Working Draft (WD) for discussion of the WG 25 meetingscheduled for September 5-6, 2001 in Copenhagen.

2. [Editor's Notes ...] are used to provide background information or to ask questions for themembers of WG 25. These editor notes and this FOREWORD will be removed in officialversions of this document.

3. Clauses 6 Wind power plant information requirements, 7 Functional requirements, and 8Communication requirements are based mainly on the "Functional Requirements onCommunication system for Wind Turbine Applications, Version 0.X, Preliminary version,31 March, 2001"

4. To provide some wind power plant specific content I have used the wind power plantmodel from a project with Vattenfall. This should be understood as an example. Basedon the approach we have to revise this model, e.g., to incorporate the information from the"Functional requirements on communication system for wind turbine applications" dated31 March, 2001, ...

5. This version 88(Schwarz)01r04_2001-08-15 takes into account the input from GordonSmith (88PT25(GSMITH)01r01.doc – 2001-08-06) and Anders Johnsson(WD1_v1_Anders.doc – 2001-08-12).

6. Note that this version of the document – intended to become the first official working draft(WD) – is still a personal draft.

7. The models, structure, base definitions, classes defined in IEC 61850-7-4 and in IEC61850-7-3, and the communication services in IEC 61850-7-2 are referenced in thisdocument to maximise the re-use of existing definitions. The result of this "re-use" has tobe discussed at our next meeting in Copenhagen. The text is written under the assump-tion that WG 25 agrees on the re-use of IEC 61850.

8. The relevant IEC 61850 documents that are re-used in this draft are: 61850-7-4 (-7-3, -7-2, -7-1, and -8-1). The current status of the first four of these documents is CDV (com-mittee draft for vote), the last one has the status CD. The author will give an introduc-tion to the concepts and contents of these documents during the next meeting inCopenhagen. And he will also introduce this draft and explain the "re-use" of IEC 61850.A comparison with concepts like IEC 60870-5-101/-103/-104 will be presented as well.

9. Added a reference to 61400-11: Acoustic noise measurement techniques. This part de-fines a list of information to be exchanged.

10. This version 88(Schwarz)01r04_2001-08-15 takes also into account the comments fromAnders Johnsson provided 2001-08-15 (88(Schwarz)01r03_2001-08-14_AJs_Comments.doc).



CONTENTS Page

FOREWORD TO VERSION 88(Schwarz)01r04_2001-08-15 ....................................................2dated 15 August 2001 .............................................................................................................2FOREWORD...........................................................................................................................8INTRODUCTION.....................................................................................................................91 Scope.............................................................................................................................102 Normative references .....................................................................................................113 Terms and definitions .....................................................................................................124 Abbreviated terms ..........................................................................................................145 Application Overview ......................................................................................................15

5.1 General .................................................................................................................155.2 Wind power plant components ...............................................................................155.3 Actors....................................................................................................................18

5.3.1 Owners ......................................................................................................185.3.2 WTGS suppliers ........................................................................................185.3.3 Operators ..................................................................................................185.3.4 Wind power plant developers .....................................................................185.3.5 External network operators ........................................................................185.3.6 Energy purchasers ....................................................................................185.3.7 Power exchange ........................................................................................185.3.8 External information source .......................................................................185.3.9 External network owners............................................................................185.3.10 Network system operator ...........................................................................185.3.11 Authorities .................................................................................................18

6 Wind power plant information requirements ....................................................................196.1 General .................................................................................................................196.2 Naming convention................................................................................................196.3 Data class requirements ........................................................................................19

6.3.1 Analogue Signals.......................................................................................196.3.2 Set point commands ..................................................................................206.3.3 Binary Signals ...........................................................................................206.3.4 Binary control commands ..........................................................................206.3.5 Alarms.......................................................................................................206.3.6 Events .......................................................................................................206.3.7 Counters....................................................................................................206.3.8 Timers .......................................................................................................206.3.9 Grouped data ............................................................................................20

7 Functional requirements .................................................................................................227.1 General .................................................................................................................227.2 Information exchange for secondary systems ........................................................227.3 Functions ..............................................................................................................22

7.3.1 Operational functions.................................................................................237.3.2 System management functions ..................................................................24



7.4 Functions ..............................................................................................................257.4.1 General .....................................................................................................257.4.2 Wind power plant functions........................................................................257.4.3 WTGS functions ........................................................................................267.4.4 Electrical system functions ........................................................................267.4.5 Meteorological system functions ................................................................27

8 Communication requirements .........................................................................................288.1 General .................................................................................................................288.2 Basic Services.......................................................................................................288.3 Data Transfer Principles ........................................................................................298.4 Different classes of data ........................................................................................29

9 Modelling approach ........................................................................................................309.1 General .................................................................................................................309.2 Reuse of definitions of IEC 61850 .........................................................................319.3 Introduction to the wind power plant information models ........................................34

9.3.1 General .....................................................................................................349.3.2 Logical node classes .................................................................................349.3.3 Data classes..............................................................................................359.3.4 Common data classes ...............................................................................35

9.4 Introduction to the information exchange ...............................................................3610 Wind power plant information model ...............................................................................37

10.1 General .................................................................................................................3710.2 Wind power plant logical node classes ..................................................................38

10.2.1 Wind power plant specific logical node classes..........................................3810.2.2 Specialised logical node classes inherited from IEC 61850-7-4..................4110.2.3 Logical node classes inherited from IEC 61850-7-4 ...................................41

10.3 Wind power plant data classes ..............................................................................4210.3.1 Wind power plant specific data classes......................................................4210.3.2 Specialised data classes inherited from IEC 61850-7-4 .............................4210.3.3 Data classes inherited from IEC 61850-7-4................................................42

10.4 Wind power plant common data classes ................................................................4310.4.1 Wind power plant specific common data classes........................................4310.4.2 Specialised common data classes inherited from IEC 61850-7-3 ...............4310.4.3 Common data classes inherited from IEC 61850-7-3 .................................43

11 Information exchange models and services ....................................................................4512 Specific mappings to communication protocols ...............................................................4613 Conformance testing ......................................................................................................47Annex A (normative) Wind power plant specific logical node classes ..................................48

A.1 General .................................................................................................................48A.2 Logical node "WTur" representing general wind turbine information.......................49A.3 Logical node "WGen" representing wind generator information ..............................49A.4 Logical node "WGrd" representing wind grid information........................................50A.5 Logical node "WNac" representing wind nacelle information ..................................51A.6 Logical node "WGer" representing wind gear information ......................................51A.7 Logical node "WBrk" representing wind brake information .....................................52A.8 Logical node "WRot" representing wind brake information .....................................52A.9 Logical node "WYaw" representing wind yaw information ......................................53



A.10 Logical node "WEnv" representing wind environment information ..........................53A.11 Logical node zero (LLN0) ......................................................................................54A.12 Logical node physical device information (LPHD) ..................................................54

Annex B (normative) Specialised logical node classes inherited from IEC 61850-7-4 ...........55B.1 General .................................................................................................................55B.2 Logical node "WXxx" representing xxx information ................................................55

Annex C (normative) Wind power plant specific data classes ..............................................56C.1 General .................................................................................................................56

Annex D (normative) Specialised data classes inherited from IEC 61850-7-4 ......................57D.1 General .................................................................................................................57

Annex E (normative) Wind power plant specific common data classes .................................58E.1 General .................................................................................................................58E.2 Common data class "NEW" ...................................................................................58

Annex F (normative) Specialised common data classes inherited from IEC 61850-7-3 .........59F.1 General .................................................................................................................59F.2 Common data class "XXX".....................................................................................59

Annex G (informative) Examples ..........................................................................................60G.1 Example 1 .............................................................................................................60

Annex H (informative) Implementation considerations ..........................................................61H.1 General .................................................................................................................61H.2 Example interfaces of a real system ......................................................................61

Index ....................................................................................................................................64



Figures Page

Figure 1 – Application model.................................................................................................15Figure 2 – System overview for wind power communication ..................................................16Figure 3 – Logical interfaces for wind power information exchange .......................................17Figure 4 – Communication between control units and SCADA...............................................28Figure 5 – Wind power plant model .......................................................................................30Figure 6 – General layering...................................................................................................31Figure 7 – Class diagram of IEC 61400-25............................................................................31Figure 8 – WPP domain profile definition ..............................................................................32Figure 9 – Application profile definition .................................................................................33Figure 10 – Profiles used for IEC 61400-25...........................................................................33Figure 11 – Class diagram of the IEC 61400-25 logical node class .......................................34Figure 12 – Class diagram of the IEC 61400-25 data classes................................................35Figure 13 – Class diagram of the IEC 61400-25 common data classes .................................36Figure H-1 – Implementation issues (example) .....................................................................62



Tables Page

Table 1 – Application area (component): Wind power plant ...................................................25Table 2 – Application area (component): WTGS....................................................................26Table 3 – Application area (component): electrical system ....................................................26Table 4 – Application area (component): Meteorological system ...........................................27Table 5 – Wind power plant specific logical node classes .....................................................38Table 6 – LN WTur ...............................................................................................................38Table 7 – LN WGen ..............................................................................................................39Table 8 – LN WGrd ...............................................................................................................39Table 9 – LN WNac...............................................................................................................39Table 10 – LN WGer .............................................................................................................40Table 11 – LN WBrk..............................................................................................................40Table 12 – LN WRot .............................................................................................................40Table 13 – LN WYaw ............................................................................................................41Table 14 – LN WEnv .............................................................................................................41Table 15 – Logical nodes specialisations ..............................................................................41Table 16 – Logical nodes inherited .......................................................................................42Table 17 – Wind power plant specific data classes ...............................................................42Table 18 – Data classes inherited and specialised ................................................................42Table 19 – Wind power plant specific common data classes .................................................43Table 20 – Common data classes inherited and specialised..................................................43Table 21 – Common data classes inherited...........................................................................43Table 22 – Profile of ACSI models and services....................................................................45Table A-1 – LN: Wind turbine (Name: WTur) .........................................................................49Table A-2 – LN: Wind generator (Name: WGen)....................................................................49Table A-3 – LN: Wind grid (Name: WGrd) .............................................................................50Table A-4 – LN: Wind nacelle (Name: WNac) ........................................................................51Table A-5 – LN: Wind gear (Name: WGer) ............................................................................51Table A-6 – LN: Wind brake (Name: WBrk) ...........................................................................52Table A-7 – LN: Wind rotor (Name: WRot) ............................................................................52Table A-8 – LN: Wind yaw (Name: WYaw) ............................................................................53Table A-9 – LN: Wind environment (Name: WEnv) ................................................................53Table A-10 – LN: Logical node node zero (Name: LLN0).......................................................54Table A-11 – LN: Physical device information (Name: LPHD)................................................54Table B-1 – LN: Wind xxx (Name: WXxx) ..............................................................................55Table C-1 – Wind power plant specific data classes..............................................................56Table D-1 – Data classes inherited and specialised ..............................................................57Table E-1 – NEW ..................................................................................................................58Table F-1 – XXX ...................................................................................................................59



INTERNATIONAL ELECTROTECHNICAL COMMISSION____________

WIND TURBINE GENERATOR SYSTEMS –

Part 25: Communications for monitoring and control of wind power plants

FOREWORD1) The IEC (International Electrotechnical Commission) is a world-wide organization for standardization compris-

ing all national electrotechnical committees (IEC National Committees). The object of the IEC is to promote in-ternational co-operation on all questions concerning standardization in the electrical and electronic fields. Tothis end and in addition to other activities, the IEC publishes International Standards. Their preparation is en-trusted to technical committees; any IEC National Committee interested in the subject dealt with may partici-pate in this preparatory work. International, governmental and non-governmental organizations liaising with theIEC also participate in this preparation. The IEC collaborates closely with the International Organization forStandardization (ISO) in accordance with conditions determined by agreement between the two organizations.

2) The formal decisions or agreements of the IEC on technical matters express, as nearly as possible, an interna-tional consensus of opinion on the relevant subjects since each technical committee has representation from allinterested National Committees.

3) The documents produced have the form of recommendations for international use and are published in the formof standards, technical reports or guides and they are accepted by the National Committees in that sense.

4) In order to promote international unification, IEC National Committees undertake to apply IEC InternationalStandards transparently to the maximum extent possible in their national and regional standards. Any diver-gence between the IEC Standard and the corresponding national or regional standard shall be clearly indicatedin the latter.

5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for anyequipment declared to be in conformity with one of its standards.

6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subjectof patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.

Recipients of this document are invited to submit, with their comments, notification ofany relevant patent rights of which they are aware and to provide supporting documen-tation.

This working draft of the International Standard IEC 61400-25 has been prepared by IECtechnical committee 88: Wind turbine systems working group 25.

The structure and content follows the results of the first meeting of WG 25.

The text of this standard is based on the approach and content of IEC 61850 (Communicationnetworks and systems in substations).



INTRODUCTION

This document provides a standard for interconnection of monitoring and control systemsfor wind power plants. It provides requirements relevant to the specification, engineering,use, testing, diagnosis, and maintenance of the information to be shared in wind powersystems.

The standard has been prepared with the anticipation that it would be applied by:

— the wind power plant manufacturer striving to reuse the information models defined in thisstandard and to meet interoperability between devices;

— the wind power plant purchaser in specifying such interoperability requirements;

— the wind power plant planner for the system integration, and

— the wind power plant testing process.

This standard re-uses the definitions specified in IEC 61850-7-4, IEC 61850-7-3, IEC 61850-7-2, IEC 61850-7-1, and IEC 61850-8-1.

Note The information models, information exchange services, and mappings to specific communication stacksfound in the referenced IEC 61850 documents are not repeated in this standard.



WIND TURBINE GENERATOR SYSTEMS –

Part 25: Communications for monitoring and control of wind power plants

1 Scope

This standard defines information, information description methods, and information ex-change for monitoring and control systems for wind power plants.

The information defined in this standard comprises mainly wind power plant specific informa-tion like status, counters, measurands, and control information of various parts of a windpower plant, e.g., turbine, generator, gear, rotor, and grid. This standard defines also a profileof generic information specified in IEC 61850-7-4 and 61850-7-3.

The information description methods are object oriented. They rely on a table notation.

The information exchange defines a client-server relation that provides:

— real-time data access and retrieval,

— controlling devices,

— event/alarm reporting and logging (publisher/subscriber),

— self-description of devices (device data dictionary),

— data typing and discovery of data types, and

— file transfer

Communication profiles are selected as appropriate.

NOTE This part does not provide implementation recommendations.



2 Normative references

The following normative documents contain provisions which, through reference in this text,constitute provisions of this International Standard. At the time of publication, the editions in-dicated were valid. All normative documents are subject to revision, and parties to agree-ments based on this International Standard are encouraged to investigate the possibility ofapplying the most recent editions of the normative documents indicated below. Members ofIEC and ISO maintain registers of currently valid International Standards.

[Editor's Note 1 – I have checked IEC 61400-11 and 61400-24 for common references forinclusion in part 25. No references seemed to be appropriate. Please provide additionalreferences you think we should add.]

IEC ... ...

IEC 61400-11 Wind turbine generator systems – Part 11: Acoustic noise measurement tech-niques

IEC 61850-6 Communication networks and systems in substations – Part 6: Substationautomation system configuration language

IEC 61850-7-1 Communication networks and systems in substations – Part 7-1: Basic com-munication structure for substations and feeder equipment – Principles andmodels

IEC 61850-7-2 Communication networks and systems in substations – Part 7-2: Basic com-munication structure for substations and feeder equipment – Abstract com-munication service interface (ACSI)

IEC 61850-7-3 Communication networks and systems in substations – Part 7-3: Basic com-munication structure for substations and feeder equipment – Common dataclasses

IEC 61850-7-4 Communication networks and systems in substations – Part 7-4: Basic com-munication structure for substations and feeder equipment – Compatible logi-cal node classes and data classes

IEC 61850-8-1 Communication networks and systems in substations – Part 8-1: SpecificCommunication Service Mapping (SCSM) – Mapping to MMS (ISO/IEC 9506Part 1 and Part 2) over ISO 8802-3



3 Terms and definitions

Fur the purposes of this International Standard, the following terms and definitions apply.

[Editor's Note 2 – Additional terms and definitions will be added as required and appro-priate.]

3.1 DeviceA mechanism or piece of equipment designed to serve a purpose or perform a function, e.g.circuit breaker, relay or power plant computer.

3.2 Event informationMonitored information on the change of state of operational equipment.

3.3 External Electrical NetworkAn electrical network to which a wind power plant is connected. A wind power plant will haveone or more connections to an external network.

3.4 FunctionFunctions are tasks that are performed in the control centre or the wind power plant by thesystem. Generally, a function consists of subfunctions that exchange data which each other.Depending on the function definition functions itself exchange data with other functions. Thereis no unique allocation of functions or subfunctions to devices. One ore more functions mayreside in a single device or be distributed among several devices at the same or at differentcontrol levels. In minimum, the most functions consist of three subfunctions, i.e. the subfunc-tions with the core functionality itself, the process interface function and the HMI (human-machine interface) function meaning human access to the function.

3.5 IEDIntelligent Electronic Device - e.g. numeric Protection relay, or Bay controller, or multi-function electronic Meter. An IED may have connections as a client, or as a server, or both,with other IEDs. An IED is, therefore, any device incorporating one or more processors, withthe capability to receive, or send, data / control from, or to, an external source.

3.6 InterfaceA shared boundary between two functional units, defined by functional characteristics, e.g.common physical interconnection characteristics, signal characteristics or other characteris-tics as appropriate, and the provision of a declared collection of services.

3.7 Periodic data transmissionTransmission of sets of data that is repeated in equal time intervals.

3.8 Point of Common ConnectionThe point at which a wind power plant is connected to the external network.

3.9 Spontaneous data transferData transfer initiated by an application process upon events or change of data.



3.10 Wind farmA Wind farm is characterised by the size and the location of the wind power plant, i.e. the ef-fects on the power network. Furthermore, the properties and functions of the wind farm aremore advanced than of a smaller wind power plant. A wind farm generally has a main con-troller for co-ordinated control of the individual wind turbines. The wind farm will typically haveits own high voltage feeder network with a number of small substations. The electrical proper-ties and behaviour of the wind farm is of such a nature, that it typically will be met with spe-cific requirements regarding power quality and reactive power compensation. In some loca-tions, the wind farm must participate actively in the regulation of the network stability.

3.11 Wind power plantA logical collection of 1 or more wind turbine systems together with associated equipmentwhich convert kinetic energy of the wind into electrical energy within a geographically con-fined area and feeds this energy into an external power network. Only those aspects aremodelled that provides or consumes information from the associated network.Note Wind power plant is the general name for a model of a single wind turbine or a wind farm

3.12 Wind turbineSystem that converts kinetic energy of the wind into electrical energy.



4 Abbreviated terms

ACSI Abstract communication service interface (defined e.g. in 61850-7-2)

CMS Control and monitoring system

O&M Operations and maintenance

SCAM Specific communication service mapping (defined e.g. in 61850-8-1)

WPP Wind power plant

WTGS Wind turbine generator system

[Editor's Note 3 – Additional abbreviations will be added as required and appropriate.]



5 Application Overview

5.1 General

The components that provide information to be described and be made available forinformation exchange for monitoring and control systems for wind power plants are listed inthe following subclauses. The application model is as depicted in Figure 1.

Component(providing

information)

Component(contains

information)

Actorinformationexchangeinformationexchange

Actor

informationexchangeinformationexchange

informationexchange

(Actor)(Actor)

Figure 1 – Application model

The standard shall provide provisions for the following:

— Components that contain information, see clause 5.2 (e.g., Control and monitoring sys-tem),

— Actors that exchange information to perform a communication function, see clause 5.3(e.g., operator),

— Information that carries specific semantic (e.g., Phase voltage),

— Information exchange services (e.g., report status, stop),

— Communication network to transport the exchanged information (e.g., Ethernet, TCP/IP).

5.2 Wind power plant components

Through the definition of information and information exchange this standard defines a windpower plant communications interface (see Figure 2). No distinction shall be made as towhether this interface is accessed locally or remotely. The standard also leaves open to putthe interface either at the wind power plant level or at a single wind turbine. Thus the standardsupports interoperability not only between the wind turbine system and SCADA but also be-tween wind turbine systems from different vendors and wind farm controllers, e.g. equipmentin the wind farm that controls and optimises the production of several wind turbines.

For the special case of a wind power plant containing a single WTGS, the single WTGS wouldhave to implement the wind power plant communications interface. This could be done by theWTGS control unit or by an additional server.



Interface Description Covered by Standard

WPP IF Wind Power Plant Communications Interface Yes

WTGS IF WTGS Communications Interface Yes

MM IF Meteorological Mast Communications Interface No?

ELEC IF Site Electrical System Communications Interface No?

[Editor's Note 4 – From an external communication point of view there may/should beno difference between the WPP IF and WTGS IF, except that the WPP IF could act as asingle entry point to the whole plant (access restriction, security, ...). The information"seen" from the external communication is the same, independent where it is made"visible". What you see is what you communicate (WYSIWYC). If a certain information isvisible, we have to define it (!) – if we retrieve it's values from the "Gateway" or "Proxy"at the edge of the WPP or through a router (at the edge) directly from the WTGS is thesame.]

CMS

Site CommsNetwork

MetMast

SubStation

Wind Power Plant

WP

P IF

WTGS IF WTGS IFWTGS IF

MM IFELEC IF

Ext

erna

lC

omm

unic

atio

ns

Figure 2 – System overview for wind power communication

[Editor's Note 5 – More details need to be included describing the WTGS.]

A wind power plant is considered to be a collection of 1 or more WTGSs. In addition to theWTGS, a wind power plant will typically contain some or all of the following components:

— External network connections.

— Site electrical system.

— External communications network.

— Site communications network.

— Meteorological masts.

— Noise monitoring equipment.



[Editor's Note 6 – IEC 61400-11 Wind turbine generator systems – Part 11:Acoustic noise measurement techniques provides a list of information. We haveto contact the MT 11 of TC 88 to get more details and background information.]

— Condition monitoring systems.

— Control and monitoring system (CMS).

— Safety and access control equipment.

The WTGSs are assumed to be autonomous units. They have a control unit which carries outall necessary sequencing, control and health monitoring for the turbine to operate. It also pro-vides a communication interface.

The WTGSs within a wind power plant are usually, but not necessarily, of the same type.

A wind power plant may, conceptually, be a collection of single WTGSs in different locationsor a collection of smaller wind power plants.

Each turbine is assumed to be connected to an electrical circuit. The site electrical system isassumed to consist of one or more electrical circuits. Each electrical circuit may be connectedeither directly to the external electrical network or may be a sub circuit of another electricalcircuit.

The site communications network allows communication between the components of a windpower plant and a central control and monitoring system within the wind power plant.

The external communications network allows communication between external devices andthe wind power plant.

The CMS system allows for control and monitoring of individual elements within a wind powerplant and implements any collective control functions of the wind power plant.

Safety and access control equipment may include any of the following:

— Access control (gates etc.)

— Fire detection systems

— Voice communication systems

— Intruder alert systems

The logical interfaces for information exchange provided by this standard are as depicted inFigure 3.

WTGS WTGS

Elec syst Met mast

WPPIF ? ?

Figure 3 – Logical interfaces for wind power information exchange



5.3 Actors

5.3.1 Owners

The wind power plant will be owned by one or more organisations. Each organisation couldown more than one wind power plant.

5.3.2 WTGS suppliers

The suppliers of the WTGSs.

5.3.3 Operators

A Wind Power Plant will be operated and maintained by an operations and maintenance(O&M) organisation. One O&M organisation may look after more than one Wind Power Plant.The O&M organisation is not necessarily the owners of the wind farm. The O&M organisationis not necessarily the suppliers of the WTGSs. Different components of the wind power plantmay be operated by different operators.

5.3.4 Wind power plant developers

The developers of the wind power plant. This may or may not be the final owners of the windpower plant. The developers may involve a number of organisations in the construction of thewind power plant.

5.3.5 External network operators

Operators of the external network to which the wind power plant is connected.

[Editor's Note 7 – Original draft lists Electrical System Operator and Electrical NetworkOperator – is there a need to distinguish?]5.3.6 Energy purchasers

Organisations which contract to purchase some or all of the energy output of a wind powerplant.

5.3.7 Power exchange

To buy/sell surplus/deficit of power.

5.3.8 External information source

Weather forecasts etc.

5.3.9 External network owners

tbd

5.3.10 Network system operator

tbd

5.3.11 Authorities

Supervises emissions etc.



6 Wind power plant information requirements

6.1 General

The different operational functions of a wind power plant need access to data in the powerplant and the sending and receiving devices must be able to encode, decode, interpret, andhandle the data as intended. Therefore, the information exchanged must be defined togetherwith the syntax, semantics and other characteristics.

Data is represented by a number of attributes. The number of attributes for a specific datamay vary. The number and formats of the attributes sent at configuration time is different thanthe number and formats of the attributes that is transmitted in any message (data transmis-sion).

Each wind power plant shall have defined the total set of data, the naming, the type and de-fault value of the data according to this specification. The information shall be standardisedaccording to the following principles:

— Each device or object shall be self-descriptive (generic part) and the system has to have afunction to extract the information contained in the wind power plants objects. It shall bepossible to issue an identify request and get a list of all objects in a wind power plant,their names and possibly a short description for each object. It should be possible to getthe attributes and services for each object. The list should at minimum include: Name,Type/Kind, Unit, Time requirements, and possibly a short Description.

— For the HMI such information shall be contained in the device using standard readabletext, such as ASCII or Unicode (UTF16) (at least optional in the language of the operator).The presentation of the information itself is out of the scope of this specification.

— At least for default naming a hierarchical name structure and an object data dictionaryspecialised for wind power plants should be used.

— During data transmission the message should at least include the following parts: Name orunique Identification, Value(s), Time tag, and Quality information.

6.2 Naming convention

The communication models and services and the information to be exchanged shall be mod-elled applying an object oriented approach. Gear and generator, for instance, could be sepa-rate objects. Each may include measurements, calculated data, and control services. Thecommunication system shall provide naming of objects (measurements, etc) in a hierarchicalnaming convention with several levels.

6.3 Data class requirements

6.3.1 Analogue Signals

All analogue process values shall be accessible in standard SI-units. Analogue values “at thesource” shall be available as real-time on-line instant data as well as time averaged values.The values shall be available for display on operator HMI as well as for storage (databases).Updating of analogue on-line values shall be selectable down to an interval of 1 sec. All aver-aged values must be stored in the plant controller for retransmission on demand. For aver-aged values the accuracy of the start time of the period shall be better than 10 ms.



Some process values are not required as measurements directly at the source. The valuesshall be accessible as processed data in a condensed and analysed format. This for instanceis the case for condition monitoring of components such as gearbox bearings.

6.3.2 Set point commands

Values for local functions shall be sent as set points. A confirmation of the set point update isrequired.

6.3.3 Binary Signals

All binary process values shall be accessible as appropriate. Binary values shall be availableas real-time on-line instant data. The values shall be available for display on operator HMI aswell as for storage (databases). The values shall be stored and displayed at level shift withthe corresponding date and time tag. Updating of binary on-line values shall be selectabledown to an interval of 1 sec.

6.3.4 Binary control commands

A handshake procedure is required for all commands that start or stop a mechanical compo-nent, influence the status or operation mode of the wind turbine or change the software. Allother control commands shall give a response with the result of the command.

Commands shall be provided for activation and deactivation of programs and parameterchanges.

6.3.5 Alarms

Operational alarms must be transmitted immediately after a triggering. A triggering is typicallyinitiated at any event that results in an automatic stop of the wind turbine, any event thatcauses an emergency stop or any other alarm-causing event. The alarms shall be availablefor display on operator HMI as well as for storage (databases).

6.3.6 Events

Operational events must be stored in an event log in the plant controller for transmission ondemand.

6.3.7 Counters

Counters shall be understood as any value accumulated in time originating in the processsuch as hour counters, production counters, counters for operational modes, timer’s etc.Counters shall be available for display on operator HMI as well as for storage (databases).The values shall be stored with a corresponding date and time tag. Updating of counters shallbe selectable down to an interval of 1 sec. All values must be stored in the plant controller fortransmission on demand.

6.3.8 Timers

Timers shall be provided to determine the time for the important states in the wind turbine,e.g. Generator on-time, Yawing time and Free to operate time. It should be possible to resetall the timers and the ‘Reset date’ shall be stored as a separate item.

6.3.9 Grouped data

Data values can be grouped based on logical relationships between the data, as chronologi-cally ordered data, as text etc. This section includes a description of different ways to put to-gether sets of data:



— Data structuresData structures typically include several kinds of related data, for example the data value,the tie stamp, the quality information, or the description of an object.

— Time series dataTime series data are time based data values for a specific object attribute, for examplesampled data, metering data, etc.

— Short text messagesIt should be possible to exchange text messages between the wind power plant and thecontrol centre using standard readable text, such as ASCII or Unicode (UTF16).

— FilesTypically files will be used for upload and download of programs etc.



7 Functional requirements

7.1 General

Basically the communication system must assist the operators, users and other interestedparties in performing their tasks by provision of services. The system should be flexible andopen in supporting future requirements and future main stream technologies. The communi-cation system must be open in the sense that in principle “anyone shall be able to get infor-mation on anything from anywhere”, once they have authorisation to the communication sys-tem. The communication system thus shall be adapted to individual users and services pro-vided accordingly by means of configurations, set-ups etc.

The communication system shall be based on open and widely accepted methods with a highdegree of interface possibilities. The system shall be robust and reliable, but the system shallnot be used for the safe and secure operation of the plant. Faults in the communication sys-tem shall not cause malfunction of an individual wind turbine. The system shall be designed ina way that faults of a sub-system interferes as little as possible with functions of the commu-nication system as a whole.

In designing the system it shall be taken into account, that the physical environment at theplant typically has a wide span of temperature, moisture, salinity and vibration levels.

7.2 Information exchange for secondary systems

Secondary systems may be for example Beacons (sea and air), Fire protection, Emergencyalarm, Intruder alarm, Power supplies and emergency power systems, Meteorological sta-tions, Safety systems for personnel, Data logger systems and Condition monitoring. Conditionmonitoring will be very important for offshore wind farms and it will be a standard function inall larger wind turbines.

The condition monitoring system provides status and analysis reports for components. Theanalysis may be in the form of spectres, trends, statistic figures, time tracking etc.

The values shall be available for display on operator HMI as well as for storage (databases).Updating of values shall be selectable down to an interval of 1 sec. All data must be stored inthe plant controller for transmission on demand. Transfer of data from the buffers may be car-ried out off-line without synchronism with real-time.

7.3 Functions

7.3.1 Overview

The functions provided in each application area shall be:

— Control

— Monitor status

— Data collection and retrieval

— Alarm and event management

— Configuration

— Software updates



These basic functions of the communication system can be grouped in two main categories:

— Operational or control functions and

— System management functions.

A third group is Process automation functions, which involve functions that operate with proc-ess data directly without the involvement of an operator. However this group is outside thescope of this standard.

7.3.2 Operational functions

The operational functions are needed for the normal daily operation of the wind power plant.In these functions an HMI, either local or remote, is included. The operational functions are

used to present process or system information to an operator or to provide him the controle.g. by commands. The operational functions include the following:

— Access security managementAccess to operational functions has to be controlled by a set of rules. Access control is toallow the capability to restrict an authenticated client to a pre-determined set of servicesand objects.

— Supervision/monitoring (Wind power plant operation and Network operation)Local or remote monitoring of the status and changes of states (indications) for opera-tional devices.

— ControlControl function allows an operator or an automatic function to operate equipment likeswitch gear or transformer, a protection, etc. Control is subject to miscellaneous filtersthat check that there will be no damage if the control is issued.

— Parameter changes (parameter set switching, subset of setting, or single parameter)In addition to single parameters, an application may have several possible pre-defined pa-rameter sets (but only one active set).

— Alarm managementAlarm is generated when a data of the system takes a value that shall be specially con-sidered by the operator, i.e. there is a need for attracting attention to some abnormalstate. Alarm management functions allow an operator to visualise, acknowledge and clearalarms.

— Event and Log managementFunctions for continuous scanning of devices for alarms, operator control actions andchanges in state, and for recording the events chronologically with date and time informa-tion.

— Data collection and retrievalFunctions for local collection of data values should include services to retrieve all or se-lected data (names, values and units).

— Data retrieval of configuration data and settingsFunctions for a follow-up of parameter settings should include services to retrieve all pa-rameters (names, values and units for all setpoints) or to retrieve only those that differfrom the default values.



— Disturbance / fault record retrievalData retrieval for the purpose if display and bulk data storage of fault data.

7.3.3 System management functions

System management functions include both functions for system support and for system con-figuration and maintenance. System support functions are used to manage the system itself(e.g. Network management, Time synchronisation, and Self-checking of communicationequipment). The functions support the total system and have no direct impact on the process.

System configuration or maintenance functions are used to set-up or evolve (maintain) thesystem. The system configuration and maintenance functions include the setting and chang-ing of configuration data and the retrieval of configuration information from the system. Themost important examples of System Management functions are:

System support

— Network managementFunctions needed to configure and maintain the communication network. The basic task isthe identification of communication objects/devices.

— Time synchronisationSynchronisation of devices within a communication system.

— Self-checkingThe self-check detects if an object or device is fully operational, partially operational ornot operational.

System configuration and maintenance

— Software managementThe software management include version control, download, activation and retrieval ofsoftware.

— Configuration managementThe function is used to download, activate and retrieve configuration data.

— Operative mode controlAllows an authorised operator to start and stop functions or objects within the system, in-cluding manual activation or reset of subsystems.

— Setting (parameter set)The setting function allows an operator read and to change on or more parameters af-fecting the behaviour of the object/device.

— Test modePossibility to check a function but avoiding impact on the process (blocking of processoutputs).

— System security managementFunction to allow control and supervision of the security of the system against unauthor-ised access or loss of activity.



7.4 Functions[Editor's Note 8 – Basic list of required functionality. Intended to be a reasonably highlevel list of requirements. The following lists comprise functions as well as data – needto differentiate these two categories. Please add to this….]7.4.1 General

The application areas covered shall be:

— Wind power plant

— WTGS functions

— Electrical system

— Meteorological data

— ?

The following subclauses provide details for each area.

7.4.2 Wind power plant functions

The wind power plant shall provide the functions, services and data as listed in Table 1.

Table 1 – Application area (component): Wind power plant

Function Service and Data

Control Shutdown wind power plant

Release power plant to run

Set power demand

Set power factor

Monitoring / Supervision Real power

Reactive power

Average wind speed

Average wind direction

Pressure

Temperature

Number of WTGS available

Number of WTGS on line

Number of turbines stopped (operator)

Number of turbines stopped (owner)

Number of turbines unknown

Data collection and retrieval Storing 10 minute statistics

Storing timers/counters

Access to historical data

Retrieve condition monitoring data

Retrieve time series data




Performance and reporting Availability

Production

Forecast output

Get wind power plant configuration information

Alarm and event management Remote alert of plant level faults

Storing of alarms and events

Configuration Change set points

Software updates Software updates to wind power plant components

7.4.3 WTGS functions

The WTGS shall provide the functions, services and data as listed in Table 2.

Table 2 – Application area (component): WTGS


Control Release to run

Stop (operator)

Stop (owner)

Reset (clear outstanding alarms but not release to run)

Set power demand (active control only)

Set power factor demand

Monitoring / Supervision Real power

Reactive power

RMS voltages (3 phases)

Rotor speed

Crew present

Data collection and retrieval Create and temporarily store 10 minute statistics

Allow transfer of stored data

Performance and reporting

Alarm and event management Remote alert of plant level faults


Configuration Change set points

Software updates Deploy software updates.

7.4.4 Electrical system functions

The electrical system shall provide the functions, services and data as listed in Table 3.

Table 3 – Application area (component): electrical system


Control Open/close breakers?




Monitoring / Supervision Phase voltages

Phase currents

Frequency

Power

Reactive power



Collection of condition monitoring data.


Alarm and event management Remote alert of faults


Triggering and retrieval of time series data at an event.

Configuration Set point changes

Software updates

7.4.5 Meteorological system functions

The 7.4.5 Meteorological system shall provide the functions, services and data as listed inTable 4.

Table 4 – Application area (component): Meteorological system

Function Service & Data

Control

Monitoring / Supervision Wind speed

Wind direction

Temperature

Pressure

Rain sensors

Icing Sensors




Alarm and event management

Configuration

Software updates



8 Communication requirements

8.1 General

In this Specification “communication system” shall be understood as a system for:

— Exchanging information from a process/plant level to a level, where information is acces-sible for an application with a standardised semantic using a standardised format

— Exchanging information to a process/plant level for distribution of commands, operationalsettings etc.

This section contains the requirements on the communication between the different units inthe system.

SCADA WFMCSWPU

Cy

SWPUCy

SWPUCU

SWPUCU

COMMUNICATION

DATADATA

COMMUNICATION(services,function)

WFMC: Wind Farm Main ControllerCU: Control UnitSWPU: Single Wind Power Unit

Figure 4 – Communication between control units and SCADA

In wind farms a local communication system might be the link between overall control unitsand the individual wind turbine controller. An overall control unit may be a “wind farm maincontroller” conducting an overall governing of the plant output and the grid compatibility.

8.2 Basic Services

The main objective for the communication system is to transfer data to and from the proc-ess/plant level. The overall purpose is to support the functions in clause 7. In order to accom-plish this the basic services of the communication system shall include the following:

— Connection establishment and release

— Authentication

— Identification of functional object and devices

— Data access and transfer

— Reliable communication over a network



8.3 Data Transfer Principles

Data can be transferred according to one of the following principles:

— Periodic data transfer (all data or only data that has changed since last transfer)

— Data transfer on demand

— Event driven (spontaneous) data transfer

— Event logging

— Command transfer

— Set point transfer

8.4 Different classes of data

The following classes of data need to be supported:

— Measurements/analogue data (signals) from the wind power plant

— Set points sent to the wind power plant

— Binary Signals/Status data from the wind power plant.

— Binary control commands to the wind power plant

— Alarms

— Events

— Counters

— Timers

— Data structures

— Time series data

— Short text messages

— Flat files

The different kinds of data can be grouped and named real time/on-line data, historical dataor forecasts/schedules. On-line data include measurements/analogue data, binary sig-nals/status data (but might also include counters). Historical data include measurement data(calculated values), counters and timers. Schedules could be start/stop schedules for individ-ual wind turbines.



9 Modelling approach

[Editor's Note 9 – If the project team reaches consensus to re-use parts of the stan-dards IEC 61850-7-x and 61850-8-1 the following is what our standard would include andlook like. This is one way of modelling the WPP information. Other options may be dis-cussed, e.g., in Copenhagen. For the time being I "re-used" the modelling approach inclause 9 (of 61400-25) and part of the content of IEC 61850 in clause 10 (of 61400-25) forlogical nodes, data, common data classes, data attributes, and services.]

9.1 General

The wind power plant shall represent a single wind turbine or a wind farm. The aspects of awind power plant defined in this standard shall cover the information and information ex-change for monitoring and control systems for wind power plants. Other aspects of the windpower plant shall be outside the scope of this standard.

The modelling approach applied in this standard relays on the definitions provided by anddefined in IEC 61850-7-1, -7-4, -7-3, and -7-2.

NOTE A comprehensive description of the approach can be found in IEC 61850-7-1. This part does not providetutorial material. It is recommended to read IEC 61850-7-1 first in conjunction with part 61850-7-4, -7-3, and -7-2.

The basic information modelling concept is shown in Figure 5. The wind power plant shall bedescribed as an information model comprising logical node classes (e.g. the informationmodel for a turbine or a generator) and data classes (e.g. a status or a measurement).

Monitored and Controlled with

IEC IEC 61400-25compliant Services and communication

Engineered and modelled

with IEC 61400-25methods

Informationmodel of

wind power

plant basedon LN and

Data classes

Figure 5 – Wind power plant model

The information shall be monitored and controlled by services provided by this standard.

The hierarchy of the models used in this standard is depicted in Figure 6. The information(e.g. status and measurements for the wind turbine) to be exchanged for monitoring and con-trol systems for wind power plants is shown at the top.



Communication profiles

Informationexchange

me

ssa

ge

s

Logical node and dataclasses, and commondata classes

Abstract communicationservice interface (ACSI)

publ./subscr., get,

set, control, ...

reporting, loggingpubl./subscr., get,

set, control, ...

reporting, logging

Ethernet, TCP/IP, OSI

Ethernet, TCP/IP, OSI

Mapping to e.g. MMS

Informationname tagged information

name tagged information

me

ssa

ge

s

Figure 6 – General layering

The main objective of this layering is to keep the (application) information free from any in-formation exchange method and communication network. This information (e.g. status of aswitch accompanied by a timestamp and a quality indication) shall be independent of any kindof information exchange methods.

The information exchange methods (e.g. reports of status information) shall be independent ofthe information to be exchanged and independent of the network used to carry the messages(e.g. TCP/IP).

The definitions of this standard are separated in these three aspects.

9.2 Reuse of definitions of IEC 61850

The class diagram in Figure 7 shows the aggregation of the wind power plant. The standardcomprises specifications inherited from IEC 61850, specialised definitions, and wind powerplant specifics.

WPP standard61400-25

Definitions in-herited from

61850

Wind powerplant specific

definitions

Specialisationsof 61850

Figure 7 – Class diagram of IEC 61400-25



This diagram is applied to all three layers covered in this standard:

— Information describing the content

— Information exchange methods

— Communication systems.

All three layer specify many classes, services, or other definitions as shown in Figure 8. Alldefinitions of all layers together shall form the wind power plant domain profile (WPP pro-file).

Layer I I1 I2 I3 I4 I5

C1 C2 C3 Cn

IE1 IE2 IE3 IE4 IEnLayer IE

Layer C

In

WPP domain profile = Layer I + Layer IE + Layer C= IEC 61400-25

...

...

...

Figure 8 – WPP domain profile definition

For specific applications just a subset of all the definitions of this standard are required. Asshown in Figure 9 a specific application profile shall be a selection of the definitions of eachlayer.

Note An application profile will be implemented in real devices.

[Editor's Note 10 – We should discuss in WG 25 if there is a requirement for a formalprofile taxonomy. The taxonomy is a classification scheme for distinguishing profiles interms of unique identifiers. Profiles may be classified as either standardized or private.]



I1 I2 I3 I4 I5

C1 C2 C3 Cn

IE1 IE2 IE3 IE4 IEn

In

Application profile = (Layer I + Layer IE + Layer C) profiles

...

...

...

Layer I profileLayer IE profile

Layer C profile

Layer I

Layer IE

Layer C

Figure 9 – Application profile definition

The relation between various parts of IEC 61850 and this standard is exposed in Figure 10.

specificLN & D(Wxxx)Profile of

IEC 61850-7-4

61850-8-1 Mapping to MMS

Abstract communication service interface (ACSI)

Common data classes and attributes

specificLN & D(Pxxx)

Common compatible logical node (BasicLN, Lxxx)and data classes

specificLN & D(Mxxx)

specificLN & D(Rxxx)

specificLN & D(Xxxx)

add. specificLN & D(Wxxx)

add. LN& D

additional mapping for WPP applications

?Profile of IEC 61850-7-3

Profile of IEC 61850-7-2

Figure 10 – Profiles used for IEC 61400-25

The specification of IEC 61850 used for this standard are shown in white boxes. The WPPspecific additions are depicted as blue shadowed boxes on the right hand side.

[Editor's Note 11 – The box with the "?" at the level of common data classes may beremoved in case we do not require additional common data classes.]



9.3 Introduction to the wind power plant information models

9.3.1 General

The information model (defined in clause 10) shall comprise:

— Logical node classes,

— Data classes, and

— Common data classes

Several classes are inherited directly from IEC 61850-7-4, -7-3, -7-2, and 8-1, other classesare specialised, or defined especially for wind power plant applications.

9.3.2 Logical node classes

The following groups of logical node classes are defined:

— wind power plant specific logical node classes (defined in clause 10.2),

— common logical node and data information inherited from IEC 61850-7-4 (the selectedprofile is defined in clause 10.2.2),

— specialised common logical node and data information inherited from IEC 61850-7-4(the selected profile is defined in clause 10.2.2),

The logical node class diagram in Figure 11 shows the logical node aggregation of the windpower plant specific logical nodes, the logical nodes inherited from IEC 61850-7-4, and thespecialisations of logical nodes of IEC 61850-7-4.

Logical nodesof 61400-25

Logical nodesof 61850-7-4clause 10.2.2

Wind powerplant specificlogical nodes

clause 10.2

Specialisationsof logical nodes

of 61850-7-4clause 10.2.2

Figure 11 – Class diagram of the IEC 61400-25 logical node class



9.3.3 Data classes

The following data classes are defined:

— data classes (types) inherited from IEC 61850-7-4 (the selected profile is defined inclause 10.3).

— specialised data classes (types) inherited from IEC 61850-7-4 (the selected profile isdefined in clause 10.3.2).

— wind power plant specific data classes (types) inherited from IEC 61850-7-3 (defined inclause 10.3.1).

The data class diagram in Figure 12 shows the common data class aggregation of the windpower plant specific common data classes, the common data classes inherited from IEC61850-7-3, and the specialisations of common data classes of IEC 61850-7-3.

Data classes of61400-25

Data classes of61850-7-3

clause 10.3

Wind powerplant specificdata classesclause 10.3.1

Specialisationsof data classes

of 61850-7-4clause 10.3.2

Figure 12 – Class diagram of the IEC 61400-25 data classes

9.3.4 Common data classes

The following common data classes are defined:

— common data classes (types) inherited from IEC 61850-7-3 (the selected profile is de-fined in clause 10.3.3).

— specialised common data classes (types) inherited from IEC 61850-7-3 (the selectedprofile is defined in clause 10.4.2).

— wind power plant specific common data classes (types) inherited from IEC 61850-7-3(defined in clause 10.4.1).

The common data class diagram in Figure 13 shows the common data class aggregation ofthe wind power plant specific common data classes, the common data classes inherited fromIEC 61850-7-3, and the specialisations of common data classes of IEC 61850-7-3.



Common dataclasses of61400-25

Common dataclasses of61850-7-3

clause 10.3.3

Wind powerplant specificcommon dataclasses clause

10.4.1

Specialisationsof common data

classes of61850-7-4

clause 10.4.2

Figure 13 – Class diagram of the IEC 61400-25 common data classes

9.4 Introduction to the information exchange

The information exchange shown in the middle of Figure 6 is defined in an abstract way.The specification shall be as defined in IEC 61850-7-2. The profile of the information ex-change models and services defined in IEC 61850-7-2 (Abstract communication service in-terface – ACSI) and referenced in this standard shall be as specified in clause 11.

The profiles of the specific communication service mappings (SCSM) of the ACSI models andservices to specific communication stacks appropriate for use in wind power plants shall be asspecified in clause 12.



10 Wind power plant information model

10.1 General

The information model applies the approach defined in IEC 61850-7-4 (logical node and dataclasses) and IEC 61850-7-3 (common data classes) to specify the wind power plant informa-tion model.

The modelling method uses tables to specify the names and detailed structures of the infor-mation. The wind power plant information model uses the table notation of IEC 61850-7. Thetables for logical nodes comprise the following rows and columns:

LN: Logical Node short description Name: Abbreviation (e.g. WTur)

Description Data Class Name CDC M/OPosition Pos DPC M... .. ... ...

Each row references one data class (data class name), a short description, the commondata class (type) of the data class, and an indication if the data class is mandatory or op-tional for this logical node class.

Data class semantic

Data class name DefinitionPos Position or status of a switch.... ...

The semantic of the data class is defined in a separate list (see IEC 61850-7-4 clause 6 "Dataclasses").

A common data classes is defined with the following rows and columns:

Common data class (CDC): (e.g. Controllable double point (DPC))

SPS Attribute Definition

Name Type FC TrgOp Value / Value Range M/O

stVal ENUMERATED sv dchg,fchg

intermediate-state (0) | off (1) | on (2) | bad-state (3)

M

... ... ... ... ... ...

A common data class comprises a list of data attributes. Each data attribute has a name, atype, an FC field (functional constraint), a Trgop field (trigger option field for reporting andlogging), a value and value range field, and an indication if the data attribute is mandatoryor optional for this common data class



10.2 Wind power plant logical node classes

10.2.1 Wind power plant specific logical node classes

10.2.1.1 List of wind power plant specific logical node classes

Table 5 lists the wind power plant specific logical node classes.

[Editor's Note 12 – The logical nodes are included as examples. The number and namesof the logical nodes to be published with this standard will be specified in the workinggroup 25]

Table 5 – Wind power plant specific logical node classes

Logical Node Description

WTur general wind turbine informationWGen wind generator informationWGrd wind grid informationWNac wind nacelle informationWGer wind gear informationWBrk wind brake informationWRot wind rotor informationWYaw wind yaw informationWEn wind turbine information

New logical nodes shall be defined according to the rules in 61870-7-4 Annex B "Rules forcreating extended private names".

These logical nodes shall contain the data classes as specified in the following sub-clauses.

[Editor's Note 13 – The measurands and status data classes are included as examples.The number and names of the data classes to be published with this standard will bespecified in the working group 25]

10.2.1.2 LN Wind turbine (LN WTur)

The LN WTur shall comprise the list of measurands and status information as defined in Table6.

Table 6 – LN WTur

Measurands Status informationEnergy G1 Free to yawEnergy G2 Free to operateEnergy consumption Free runTotal time Safety chainTime G1 ErrorTime G2 WarningTime with fault status Remote control from info possibleTime with grid ok Reset levelTime with wind for prod Status Code

Active fault codeActive fault code2Active fault code3Active fault code4

The logical node and data classes details shall be as defined in A.2.



10.2.1.3 LN Wind generator (LN WGen)

The LN WGen shall comprise the list of measurands and status information as defined in Ta-ble 7.

Table 7 – LN WGen

Measurands Status informationGenerator speed Thyristor openingDuty factor sent to generator Generator connectedSlip Heat generator (order)Gen current (Weier) Status word from WeierGen bearing tempGenerator tempGenerator 2 temp


10.2.1.4 LN Wind grid (LN WGrd)

The LN WGrd shall comprise the list of measurands and status information as defined in Ta-ble 8.

Table 8 – LN WGrd

Measurands Status informationPower Phase compensation (order)CosphiVoltage L1Voltage L2Voltage L3Current L1Current L2Current L3Reactive powerFrequency


10.2.1.5 LN Wind nacelle (LN WNac)

The LN WNac shall comprise the list of measurands and status information as defined in Ta-ble 9.

Table 9 – LN WNac

Measurands Status informationAcceleration X Water pump (order)Acceleration Y Ventilator nacelle (order)Vibration X maxVibration Y maxVibration X RMSVibration Y RMSNacelle tempPower panel tempWater to cooler tempWater from cooler temp




10.2.1.6 LN Wind gear (LN WGer)

The LN WGer shall comprise the list of measurands and status information as defined in Ta-ble 10.

Table 10 – LN WGer

Measurands Status informationGear oil temp Oil pump (order)Gear oil 2 temp


10.2.1.7 LN Wind brake (LN WBrk)

The LN WBrk shall comprise the list of measurands and status information as defined in Table11.

Table 11 – LN WBrk

Measurands Status informationCaliper 1 Brake proc. 50Caliper 2 Brake proc. 75

Brake proc. 199Brake proc. 200Disk brake 1 activated (order)Disk brake 2 activated (order)Soft brake (order)Hydraulic pump brake (order)


10.2.1.8 LN Wind rotor (LN WRot)

The LN WRot shall comprise the list of measurands and status information as defined in Table12.

Table 12 – LN WRot

Measurands Status informationRotor speed Hydraulic pump hub (order)Rotor position Hub hydraulic, pump (current feedback)

Hub hydraulic, solenoid (current feedback)




10.2.1.9 LN Wind yaw (LN WYaw)

The LN WYaw shall comprise the list of measurands and status information as defined in Ta-ble 13.

Table 13 – LN WYaw

Measurands Status informationYaw pressure Yaw CCWYaw missalignment Yaw CWYaw missalignment 2 Auto rewinding cablesCable twist Hydraulic pump yaw (order)Yaw speedYaw oil temp


10.2.1.10 LN Wind environment (LN WEnv)

The LN WEnv shall comprise the list of measurands and status information as defined in Ta-ble 14.

Table 14 – LN WEnv

Measurands Status informationWind speed Heat wind gauges (order)Wind speed 2Outdoor tempAir pressure


10.2.2 Specialised logical node classes inherited from IEC 61850-7-4

The specialisations of logical nodes of IEC 61850-7-4 listed in Table 15 and the data classesused in these logical nodes shall be part of this standard.

Table 15 – Logical nodes specialisations

generalized Logical Node Abbrev. IEC 61850-7-4 clause Description of specialization... ... ...

The detailed specialization shall be as defined in Annex B.

10.2.3 Logical node classes inherited from IEC 61850-7-4

The logical nodes of IEC 61850-7-4 listed in Table 16 and the data classes used in these logi-cal nodes shall be part of this standard.

Note The required data classes for the logical nodes in Table 16 are not repeated in this standard.



Table 16 – Logical nodes inherited

Logical Node Abbrev. IEC 61850-7-4 clause commentBasic logical node - 5.3.1Logical node zero LLN0 5.3.2Physical device information LPHD 5.3.3Measurement Unit MMXU 5.10.1Metering MMTR 5.10.2

For all substation related applications within a wind power plant the logical nodes and dataclasses of IEC 61850-7-4 and the associated common data classes shall be used.

[Editor's Note 14 – The above listed logical nodes may not be complete.]Specialisations of the referenced logical nodes and data classes of IEC 61850-7-4 shall be asdefined in 10.2.2.

10.3 Wind power plant data classes

10.3.1 Wind power plant specific data classes

The wind power plant specific data classes listed in Table 17, their common data class, andtheir semantic shall be part of this standard.

Table 17 – Wind power plant specific data classes

Data name......

For all substation related applications within a wind power plant the data classes of IEC61850-7-4 and the associated data attributes shall be used.

The detailed wind power plant specific data classes shall be as defined in Annex C.

10.3.2 Specialised data classes inherited from IEC 61850-7-4

The specialised data classes of IEC 61850-7-4 listed in Table 18, their common data class,and their semantic shall be part of this standard.

Table 18 – Data classes inherited and specialised

Data name......

For all substation related applications within a wind power plant the data classes of IEC61850-7-4 and the associated data attributes shall be used.

The detailed specialisations shall be as defined in Annex D.

10.3.3 Data classes inherited from IEC 61850-7-4

All data classes required by all logical node classes provided by the standard (to be used ininherited, specialised, and wind power specific logical nodes) are inherited from IEC 61850-7-4.



10.4 Wind power plant common data classes

10.4.1 Wind power plant specific common data classes

The wind power plant specific common data classes listed in Table 19 and the data attributesused in these common data classes shall be part of this standard.

Table 19 – Wind power plant specific common data classes

Common data classes Abbrev.... ...... ...

For all substation related applications within a wind power plant the common data classes ofIEC 61850-7-3 and the associated data attributes shall be used.

The detailed wind power plant specific common data classes shall be as defined in Annex E.

10.4.2 Specialised common data classes inherited from IEC 61850-7-3

The specialised common data classes of IEC 61850-7-3 listed in Table 20 and the data attrib-utes used in these common data classes shall be part of this standard.

Table 20 – Common data classes inherited and specialised

Common data classes Abbrev.... ...... ...


The detailed specialisations shall be as defined in Annex F.

10.4.3 Common data classes inherited from IEC 61850-7-3

The common data classes of IEC 61850-7-3 listed in Table 21 and the data attributes used inthese common data classes shall be part of this standard.

Table 21 – Common data classes inherited

Common data classes Abbrev. IEC 61850-7-3 clause comment

Single point status SPS 6.4.2

Integer status ISI 6.4.4

Name plate PLATE 6.4.7

Binary counter reading BCR 6.4.8

Measured value MV 6.5.2

Y three phase measurements WYE 6.5.3

Delta three phase measurements DEL 6.5.4

Harmonic value for WYE HVWYE 6.5.6

Harmonic value for DEL HVDEL 6.5.7

Controllable single point SPC 6.6.2

Controllable double point DPC 6.6.3

Controllable integer status ISC 6.6.4

Analogue set point ASP 6.7.2




[Editor's Note 15 – The above listed common data classes may not be complete.]



11 Information exchange models and services

The information exchange models and services shall be as specified in the profile of the ACSIservices of IEC 61850-7-2 shown in Table 22.

[Editor's Note 16 – As long as the ACSI provides sufficient exchange models and serv-ices no additional models and services are defined in this clause.]

Table 22 lists all ACSI service models and services selected.

Table 22 – Profile of ACSI models and services

Service model Description Services M/O

Server Represents the external visible behaviour of a device.All other ACSI models are part of the server.

ServerDirectory M

Application as-sociation

provision of how two or more devices can be con-nected. Provides different views to a device: re-stricted access to the server's information and func-tions.

AssociateAbortRelease

M

Logical device Represents a group of functions; each function isdefined as a logical node.

LogicalDeviceDirectory M

Logical node Represents a specific function of the substation sys-tem, e.g., wind turbine.

LogicalNodeDirectory M

Data Provides a means to specify typed information, e.g.,position of a switch with quality information, andtimestamp.

GetDataValuesSetDataValuesGetDataDefinitionGetDataDirectory

MOMM

Data set Allow to group various data together. GetDataSetValueSetDataSetValueCreateDataSetDeleteDataSetGetDataSetDirectory

MOOOM

Substitution Supports to replace a process value by a manuallyentered value.

SubstituteUnSubstitute

OO

Reporting andlogging

Describes the conditions for generating reports andlogs based on parameters set by the client. Reportsmay be triggered by changes of process data values(e.g., state change or deadband) or by qualitychanges. Logs can be queried for later retrieval.

Reports may be send immediately or deferred (buff-ered). Reports provide change-of-state and se-quence-of-events information exchange.

ReportGetNextBufReportControlGetReportControlAttributeValueSetReportControlAttributeValueGetLogControlValueSetLogControlValueQueryLogByTimeQueryLogByEntryGetLogStatusValue

MOMMOOOOO

Control Describes the services to control, e.g., devices orparameter setting groups.

SelectSelectWithValueCancelOperateCommandTerminationSynchrocheckTimeActivatedOperate

OOOOOOO

Time and timesynchronisation

Provides the time base for the device and system. O

File transfer defines the exchange of huge data blocks like pro-grams.

GetFileSetFileDeleteFileFileDirectory

OOOO

The conformance statement of the SCSM applied shall be used to describe the details of theservices selected.



12 Specific mappings to communication protocols

The mapping shall be as specified in IEC 61850-8-1 as required for the profile of servicemodels according to Table 22.

[Editor's Note 17 – Additional mappings will be added when required.]



13 Conformance testing

The conformance testing shall be as specified in IEC 61850-10.

[Editor's Note 18 – Additional requirements will be added when required.]



Annex A (normative)

Wind power plant specific logical node classes

A.1 General

This annex specifies the details of the wind power plant specific logical node classes.

The following rules shall apply to the use of data classes of the wind power plant specific logi-cal nodes:

— The data classes shall be as defined in 10.3.1 Wind power plant specific data classes ifdefined there, else

— The data classes shall be as defined in 10.3.2 Specialised data classes inherited from IEC61850-7-4 if defined there, else

— The data classes shall be as defined in 10.3.3 Data classes inherited from IEC 61850-7-4

The following rules shall apply to the use of common data classes of the wind power plantspecific logical nodes:

— The common data classes shall be as defined in 10.4.1 Wind power plant specific com-mon data classes if defined there, else

— The common data classes shall be as defined in 10.4.2 Specialised common data classesinherited from IEC 61850-7-3 if defined there, else

— The common data classes shall be as defined in 10.4.3 Common data classes inheritedfrom IEC 61850-7-3

Note The tables "Table 2 – Basic Logical Node information ", "Table 4 – Measurands", and "Table 8 – Statusinformation" refer to IEC 6850-7-4. Details of the data class structures of the data classes used can be found inIEC 61850-7-4 clause 6 "Data classes".



A.2 Logical node "WTur" representing general wind turbine information

This logical node shall comprise the data classes that represent the general wind turbine in-formation according to Table A-1.

Table A-1 – LN: Wind turbine (Name: WTur)

Data Description Data ClassName

CDC M/O Unit

Table 2 – Basic Logical Node informationMode Mode ISC MBehaviour Beh ISI MHealth Health ISI MName plate Name PLATE MResetable operation counter OperCntRs ISC O

Table 4 – MeasurandsEnergy G1 WhG1 MV M kWhEnergy G2 WhG2 MV M kWhEnergy consumption WhConspt MV M kWhTotal time TimeTotal MV M hTime G1 TimeG1 MV M hTime G2 TimeG2 MV M hTime with fault status TimeFltSt MV M hTime with grid ok TimeGridOk MV M hTime with wind for prod TimeWndProd MV M h

Table 8 – Status informationFree to yaw FreeToYaw SPS MFree to operate FreeToOp SPS MFree run FreeRun SPS MSafety chain SafeChn SPS MError Error SPS MWarning Warn SPS MRemote control from info possible RemCtlInf SPS MReset level RstLvl ISI MStatus Code StCod ISI MActive fault code ActvFltCod ISI MActive fault code2 ActvFltCod2 ISI MActive fault code3 ActvFltCod3 ISI MActive fault code4 ActvFltCod4 ISI M

A.3 Logical node "WGen" representing wind generator information

This logical node shall comprise the data classes that represent the general wind generatorinformation according to Table A-2.

Table A-2 – LN: Wind generator (Name: WGen)


CDC M/O Unit


Table 4 – Measurands




CDC M/O Unit

Generator speed GenSpeed MV M rpmDuty factor sent to generator DFacSToGen MV MSlip Slip MV M %Gen current (Weier) GenA MV M AGen bearing temp GenBeTemp MV M °CGenerator temp GenTemp MV M °CGenerator 2 temp Gen2Temp MV M °C

Table 8 – Status informationThyristor opening Tyropen SPS MGenerator connected GenCon SPS MHeat generator (order) HeatGen SPS MStatus word from Weier SWW ISI M

A.4 Logical node "WGrd" representing wind grid information

This logical node shall comprise the data classes that represent the general wind grid infor-mation according to Table A-3.

Table A-3 – LN: Wind grid (Name: WGrd)


CDC M/O Unit


Table 4 – MeasurandsPower Power MV M kWCurrent L1 APhsA MV M ACosphi CosPhi MV M -Voltage L1 VPhsA MV M VVoltage L2 VPhsB MV M VVoltage L3 VPhsC MV M VCurrent L1 APhsA MV M ACurrent L2 APhsB MV M ACurrent L3 APhsC MV M AReactive power VAr MV M kVArFrequency Hz MV M Hz

Table 8 – Status informationPhase compensation (order) PhCom SPS M



A.5 Logical node "WNac" representing wind nacelle information

This logical node shall comprise the data classes that represent the general wind nacelle in-formation according to Table A-4.

Table A-4 – LN: Wind nacelle (Name: WNac)

Data Description Data Class Name CDC M/O UnitTable 2 – Basic Logical Node information

Mode Mode ISC MBehaviour Beh ISI MHealth Health ISI MName plate Name PLATE MResetable operation counter OperCntRs ISC O

Table 4 – MeasurandsAcceleration X AccX MV M m/s2Acceleration Y AccY MV M m/s2Vibration X max VibXMax MV M mm/sVibration Y max VibYMax MV M mm/sVibration X RMS VibXRMS MV M mm/sVibration Y RMS VibYRMS MV M mm/sNacelle temp NaclTemp MV M °CPower panel temp PwrPnlTemp MV M °CWater to cooler temp WtrToClrTemp MV M °CWater from cooler temp WtrFrmClrTemp MV M °C

Table 8 – Status informationWater pump (order) WtrPump SPS MVentilator nacelle (order) VentNac SPS

A.6 Logical node "WGer" representing wind gear information

This logical node shall comprise the data classes that represent the general wind gear infor-mation according to Table A-5.

Table A-5 – LN: Wind gear (Name: WGer)



Table 4 – MeasurandsGear oil temp GeaOilTemp MV M °CGear oil 2 temp GeaOil2Temp MV M °C

Table 8 – Status informationOil pump (order) OilPump SPS M



A.7 Logical node "WBrk" representing wind brake information

This logical node shall comprise the data classes that represent the general wind brake infor-mation according to Table A-6.

Table A-6 – LN: Wind brake (Name: WBrk)



Table 4 – MeasurandsCaliper 1 Calip1 MV M mmCaliper 2 Calip2 MV M mm

Table 8 – Status informationBrake proc. 50 Brake50 SPS MBrake proc. 75 Brake75 SPS MBrake proc. 199 Brake199 SPS MBrake proc. 200 Brake200 SPS MDisk brake 1 activated (order) DiskBrk1 SPS MDisk brake 2 activated (order) DiskBrk2 SPS MSoft brake (order) SoftBrk SPS MHydraulic pump brake (order) HydPmpBrk SPS M

A.8 Logical node "WRot" representing wind brake information

This logical node shall comprise the data classes that represent the general wind rotor infor-mation according to Table A-7.

Table A-7 – LN: Wind rotor (Name: WRot)


CDC M/O Unit


Table 4 – MeasurandsRotor speed RotSpd MV M rpmRotor position RotPos MV M

Table 8 – Status informationHydraulic pump hub (order) HydPmpHub SPS MHub hydraulic, pump (current feedback) HubHydrPump SPS MHub hydraulic, solenoid (current feedback) HubHydrSole SPS M



A.9 Logical node "WYaw" representing wind yaw information

This logical node shall comprise the data classes that represent the general wind yaw infor-mation according to Table A-8.

Table A-8 – LN: Wind yaw (Name: WYaw)



Table 4 – MeasurandsYaw pressure YawP MV M MPaYaw missalignment YawMalgmt MV M °Yaw missalignment 2 YawMalgmt2 MV M °Cable twist CablTwst MV M °Yaw speed Yawspd MV M °/sYaw oil temp YawOilTemp MV M °C

Table 8 – Status informationYaw CCW YawCCW SPS MYaw CW YawCW SPS MAuto rewinding cables AuRewCab SPS MHydraulic pump yaw (order) HydPmpYaw SPS M

A.10 Logical node "WEnv" representing wind environment information

This logical node shall comprise the data classes that represent the general wind environmentinformation according to Table A-9.

Table A-9 – LN: Wind environment (Name: WEnv)



Table 4 – MeasurandsWind speed WindSpd MV M m/sWind speed 2 WindSpd2 MV M m/sOutdoor temp OutdrTemp MV M °CAir pressure AirPres MV M hPa

Table 8 – Status informationHeat wind gauges (order) HeatWndGau SPS M



A.11 Logical node zero (LLN0)

This logical node shall comprise all data classes that represent the common information of thelogical device and (may be) the external equipment (i.e. the power plant controller) ac-cording to Table A-10.

Table A-10 – LN: Logical node node zero (Name: LLN0)

Data Description Data Class Name CDC M/OTable 2 – Basic Logical Node information

Mode Mode ISC MBehaviour Beh ISI MHealth Health ISI MName plate Name PLATE MOperation hours Operh ISI ORun Diagnostics Diag SPC OLED reset LEDRs SPC OExternal equipment health (i.e. the power plant controller) EEHealth ISI OExternal equipment name plate (i.e. the power plant con-troller)

EEName PLATE O

A.12 Logical node physical device information (LPHD)

This logical node shall comprise all data classes that represent the common information of thephysical device that hosts the logical device according to Table A-11.

Table A-11 – LN: Physical device information (Name: LPHD)

Data Name Data Class Name CDC M/OTable 3 – Physical device information

Physical device name plate PhName PLATE MPhysical device health PhHealth ISI MOutput communications buffer overflow OutOvrFlw SPS OInput communications buffer overflow InOvrFlw SPS ONumber of Power ups NumPwrUp ISI ONumber of Warm Starts WrmStarts ISI ONumber of watchdog device resets detected WacTrg ISI OPower Up detected PwrUp SPS OPower Down detected PwrDn SPS OExternal power supply alarm PwrSupAlm SPS OReset device statistics RsStat SPC O



Annex B (normative)

Specialised logical node classes inherited from IEC 61850-7-4

B.1 General

This annex specifies the details of the wind power plant specific logical nodes.

B.2 Logical node "WXxx" representing xxx information

This logical node shall comprise the data classes that represent the general wind WXxx in-formation according to Table B-1.

Table B-1 – LN: Wind xxx (Name: WXxx)


CDC M/O Unit

Table 2 – Basic Logical Node information... ... ... ...

Table 4 – Measurands... ... ... ... ...

Table 8 – Status information... ... ... ......

Table yy – yxyx... ... ... ...



Annex C (normative)

Wind power plant specific data classes

C.1 General

This annex specifies the details of the wind power plant specific data classes.

Table C-1 – Wind power plant specific data classes

Data name Definition... ...... ...



Annex D (normative)

Specialised data classes inherited from IEC 61850-7-4

D.1 General

This annex specifies the details of the wind power plant specialised data classes inheritedfrom IEC 61850-7-4.

Table D-1 – Data classes inherited and specialised

Data name Definition/specialisation... ...... ...



Annex E (normative)

Wind power plant specific common data classes

E.1 General

This annex specifies the details of the wind power plant specific common data classes.

E.2 Common data class "NEW"

Table E-1 defines the common data class “NEW”.

Table E-1 – NEW

NEW Attribute Definition


... ... ... ... ... ...

... ... ... ... ... ...

...



Annex F (normative)

Specialised common data classes inherited from IEC 61850-7-3

F.1 General

This annex specifies the details of the specialised common data classes from IEC 61850-7-3..

F.2 Common data class "XXX"

Table E-1 defines the specialised common data class “XXX”.

Table F-1 – XXX

XXX Attribute Definition


... ... ... ... ... ...

... ... ... ... ... ...

...



Annex G (informative)

Examples

G.1 Example 1

This ...

[Editor's Note 19 – To help people to understand the general concept and details (tosome extent) a realistic example will included.]



Annex H (informative)

Implementation considerations

H.1 General

This standard does not constrain any implementation of the information, service models andcommunication stacks.

To give some guidance in the understanding of the standard, the following discussion of anexample is intended to show what the standard covers compared with to a real system.

Note – The example is not representative. Many other possible interfaces on both sides are possible.

H.2 Example interfaces of a real system

The co-operation of wind power plant (WPP) devices and supervisory and control systemsmainly comprises – according to Figure H-1 – interfaces and actions described from right toleft:

— The data value source is the real WPP. The exchange of data (raw) values between thereal WPP process and the WPP server is realised with Interface 1 (IF1) and (IF2) – thisinterface is implementation specific.

— The WPP server adds useful information to the (raw) process data (e.g., time stamp,quality, ...). This is defined as the action 1 (Act1) – this action is implementation spe-cific.

— The model of the information (as it is seem from the network point of view) is defined bythe standard – the model realisation is implementation specific. The model is virtual.

— Monitor value changes of process data values delivered from the real-time data sourcerepresented by (Act1) – implementation specific, but behaviour and services definedin the standard.

— Exchange data values between WPP server and supervisory and control systems via(IF3) – behaviour and services defined in the standard.

— Exchange model description located in the server with another system (IF3) – behaviourand services defined in the standard.

— Exchange of data values between (communication) client and client application (visualisa-tion, HMI) via (IF4) and (Act2) – implementation specific



WindPower Plantdata values

WPP Server, WPP device model,

ServicesWPP Client

SCADAVisualization

HMI

Network

IF2

IF3

IF4

Act1Act2

DLL

TCP/IP

RS 232

RealWPP

?

IF1

Model/behavior

Scope

Figure H-1 – Implementation issues (example)



Bibliography

[1] Functional Requirements on Communication system for Wind Turbine Applications,Version 0.X, Preliminary version, 31 March, 2001



Index

AACSI models and services ..................... 47Application association .......................... 47

Bbasic information modelling.................... 32

CCommon data classes...................... 36, 37Communication profiles.................... 11, 34Control................................................... 47control systems...................................... 10controlling devices ................................. 11

DData....................................................... 47Data classes .................................... 36, 37Data set ................................................. 47data typing............................................. 11diagnosis ............................................... 10

Eengineering............................................ 10event/alarm reporting ............................. 11

Iinformation....................................... 11, 16information description methods ...... 11, 16information exchange................. 11, 16, 38interoperability ....................................... 10

Llogging................................................... 11Logical device........................................ 47

Logical node...........................................47Logical node classes ..............................36

Mmaintenance...........................................10monitoring ..............................................10

Pprofiles of IEC 61850..............................35publisher/subscriber ...............................11

Rreal-time.................................................11Reporting and logging ............................47reuse......................................................10

Sself-description .......................................11Server ....................................................47Substitution ............................................47

TTime and time synchronisation ...............47

WWBrk ......................................................40WEn .......................................................40WGen.....................................................40WGer .....................................................40WGrd .....................................................40WNac .....................................................40WRot ......................................................40WTur ......................................................40WYaw.....................................................40

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