IEC 61850-7-1:2003

Communication networks and systems in substations - Part 7-1: Basic communication structure for substation and feeder equipment - Principles and models

Provides an overview of the architecture for communication and interactions between substation devices such as protection devices, breakers, transformers, substation hosts, etc. Uses simple examples of functions to describe the concepts and methods applied in the IEC 61850 series. Also describes the relationships between other parts of the IEC 61850 series and defines how inter-operability is reached.
This publication is of core relevance for Smart Grid.

General Information

• Status: Published
• Publication Date: 22-Jul-2003
• ICS: 33.200 - Telecontrol. Telemetering
• Technical Committee: TC 57 - Power systems management and associated information exchange
• Drafting Committee: WG 10 - TC 57/WG 10
• Current Stage: DELPUB - Deleted Publication
• Completion Date: 15-Jul-2011

Relations

• Revised: IEC 61850-7-1:2011 - Communication networks and systems for power utility automation - Part 7-1: Basic communication structure - Principles and models
• Effective Date: 05-Sep-2023

Standards Content (Sample)

INTERNATIONAL IEC
STANDARD
61850-7-1
First edition
2003-07
Communication networks and systems
in substations –
Part 7-1:
Basic communication structure
for substation and feeder equipment –
Principles and models
Reference number
Publication numbering
As from 1 January 1997 all IEC publications are issued with a designation in the
60000 series. For example, IEC 34-1 is now referred to as IEC 60034-1.
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edition numbers 1.0, 1.1 and 1.2 refer, respectively, to the base publication, the
base publication incorporating amendment 1 and the base publication incorporating
amendments 1 and 2.
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INTERNATIONAL IEC
STANDARD
61850-7-1
First edition
2003-07
Communication networks and systems
in substations –
Part 7-1:
Basic communication structure
for substation and feeder equipment –
Principles and models
 IEC 2003  Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: [phone] Telefax: [phone] E-mail: [e-mail]  Web: www.iec.ch
PRICE CODE
Commission Electrotechnique Internationale
XE
International Electrotechnical Commission
Международная Электротехническая Комиссия
For price, see current catalogue

– 2 – 61850-7-1  IEC:2003(E)
CONTENTS
FOREWORD . 7
INTRODUCTION .9
1 Scope .11
2 Normative references.12
3 Terms and definitions .12
4 Abbreviated terms.13
5 Overview of concepts the IEC 61850 series .13
5.1 Objective .13
5.2 Topology and communication functions of substation automation systems.14
5.3 The information models of substation automation systems.15
5.4 Applications modelled by logical nodes defined in IEC 61850-7-4 .16
5.5 The semantic is attached to data .19
5.6 The services to exchange information.21
5.7 Services mapped to concrete communication protocols .22
5.8 The configuration of a substation .23
5.9 Summary .23
6 Modelling approach of the IEC 61850 series .24
6.1 Decomposition of application functions and information .24
6.2 Creating information models by stepwise composition .26
6.3 Example of an IED composition .29
6.4 Information exchange models .29
7 Application view.42
7.1 Introduction .42
7.2 First modelling step – Logical nodes and data .44
8 Device view .47
8.1 Introduction .47
8.2 Second modelling step – logical device model .47
9 Communication view.49
9.1 The service models of the IEC 61850 series .49
9.2 The virtualisation .52
9.3 Basic information exchange mechanisms.53
9.4 The client-server building blocks.54
9.5 Interfaces inside and between devices.57
10 Where physical devices, application models and communication meet.58
11 Relationships between IEC 61850-7-2, IEC 61850-7-3 and IEC 61850-7-4.59
11.1 Refinements of class definitions .59
11.2 Example 1 – Logical node and data class .60
11.3 Example 2 – Relationship of IEC 61850-7-2, IEC 61850-7-3, and
IEC 61850-7-4 .62
12 Mapping the ACSI to real communication systems .64
12.1 Introduction .64
12.2 Mapping example (IEC 61850-8-1).66

61850-7-1  IEC:2003(E) – 3 –
13 Formal specification method .71
13.1 Notation of ACSI classes .71
13.2 Class modelling .72
13.3 Service tables.77
13.4 Referencing instances .78
14 Name spaces.80
14.1 General .80
14.2 Name spaces defined in IEC 61850-7-x .82
14.3 Specification of name spaces .85
14.4 Attributes for references to name spaces.87
14.5 Common rules for extensions of name spaces .89
15 Approaches for the definition of a new semantic .91
15.1 General .91
15.2 Semantic for new definition.92
15.3 Approach 1 (fixed semantic) .92
15.4 Approach 2 (flexible semantic).92
15.5 Approach 3 (reusable flexible semantic) .93
Annex A (informative) Overview of IEC 61850-7-x, IEC 61850-8-x, and IEC 61850-9-x .94
Annex B (informative) Allocation of data to logical nodes .97
Annex C (informative) Use of the substation configuration language (SCL) .100
Annex D (informative) Applying the LN concept to options for future extensions.102
Annex E (informative) Relation between logical nodes and PICOMs.107 ®
Annex F (informative) Relation between IEC 61850-7-x (IEC 61850-8-x) and UCA 2.0 .108
Bibliography.109
Index.111
Figure 1 – Sample substation automation topology.14
Figure 2 – Modelling approach (conceptual) .15
Figure 3 – Logical node information categories .18
Figure 4 – Build up of devices (principle).18
Figure 5 – Position information depicted as a tree (conceptual).19
Figure 6 – Service excerpt .21
Figure 7 – Example of communication mapping.22
Figure 8 – Summary.24
Figure 9 – Decomposition and composition process (conceptual).25
Figure 10 – XCBR1 information depicted as a tree .28
Figure 11 – Example of IED composition.29
Figure 12 – Output and Input model (principle).30
Figure 13 – Output model (step 1) (conceptual).31
Figure 14 – Output model (step 2) (conceptual).31
Figure 15 – GSE output model (conceptual) .32
Figure 16 – Setting data (conceptual).33

– 4 – 61850-7-1  IEC:2003(E)
Figure 17 – Input model for analogue values (step 1) (conceptual).34
Figure 18 – Deadbanded value (conceptual) .35
Figure 19 – Input model for analogue values (step 2) (conceptual).35
Figure 20 – Range values .36
Figure 21 – Reporting and logging model (conceptual).36
Figure 22 – Data set members and reporting.37
Figure 23 – Buffered report control block (conceptual) .38
Figure 24 – Buffer time.39
Figure 25 – Data set members and inclusion-bitstring .40
Figure 26 – Log control block - conceptual .40
Figure 27 – Peer-to-peer data value publishing model (conceptual).41
Figure 28 – Real world devices .43
Figure 29 – Logical nodes and data (IEC 61850-7-2).44
Figure 30 – Simple example of modelling .45
Figure 31 – Basic building blocks .45
Figure 32 – Logical nodes and PICOM .46
Figure 33 – Logical nodes connected (outside view in IEC 61850-7-x) .
...

This PDF file has been prepared by TC 57 experts and is made
available to assist the users of the IEC 61850-7 series.

Please note:
ƒ There was no IEC vote on these files, and IEC Central Office does
therefore not take any responsibility as to their contents.

ƒ Adobe Acrobat 6.0 is required to navigate through this file.

Any comments on these files are to be communicated to the following
address:
Karlheinz Schwarz
([e-mail])
IEC 61850 - Communication networks and systems in substations
Informative tutorial on the object models
NOTE 1 These pdf files (html pages) are intended to provide a hypertext version of an excerpt of the main
concepts and definitions of Parts IEC 61850-7-4, IEC 61850-7-3, and IEC 61850-7-2.
NOTE 2 The content of these files is informative only. They do in no way replace the normative definitions
contained in the above referenced documents.
There are the following pages to browse and study the object models:
1. Modeling approach of logical nodes (one page - pdf)
2. IEC 61850-7-2 Overview of ACSI models
3. Logical nodes of 61850-7-4
4. Common data classes in a single window
The xml files containg the models are (not available in the pdf format):
- Logical Nodes from IEC 61850-7-4:2003 LN.xml
- DATA Semantics from IEC 61850-7-4:2003 Data-Sematic.xml
- DATA-Attributes from IEC 61850-7-3:2003 CDC.xml
- DATA-Attribute Semantics from IEC 61850-7-3:2003 DA-Semantic.xml
- Common Data Attributes from IEC 61850-7-3:2003 CDA.xml
These xml files can be used to produce any other presentation. They should not be used as normative
xml documents.
Parts of the standard
�   IEC 61850-1, Part 1: Introduction and overview
�   IEC 61850-2, Part 2: Glossary
�   IEC 61850-3, Part 3: General requirements
�   IEC 61850-4, Part 4: System and project management
�   IEC 61850-5, Part 5: Communication requirements for functions and devices models
�   IEC 61850-6, Part 6: Configuration description language for communication in electrical
substations related to IEDs
�   IEC 61850-7-1, Part 7-1: Basic communication structure for substation and feeder equipment -
Principles and models
�   IEC 61850-7-2, Part 7-2: Basic communication structure for substation and feeder equipment -
Abstract communication service interface (ACSI)
�   IEC 61850-7-3, Part 7-3: Basic communication structure for substation and feeder equipment -
Common data classes
�   IEC 61850-7-4, Part 7-4: Basic communication structure for substation and feeder equipment -
Compatible logical node classes and data classes
�   IEC 61850-8-1, Part 8-1: Specific communication service mapping (SCSM) - Mappings to MMS

(ISO/IEC 9506-1 and ISO/IEC 9506-2) and to ISO/IEC 8802-3
�   IEC 61850-9-1, Part 9-1: Specific communication service mapping (SCSM) - Sampled values
over serial unidirectional multidrop point to point link
�   IEC 61850-9-2, Part 9-2: Specific communication service mapping (SCSM) - Sampled values
over ISO/IEC 8802-3
�   IEC 61850-10, Part 10: Conformance testing
The web pages and the corresponding xml files have been created by
Karlheinz Schwarz, SCC. ([e-mail])
SCC does not take any responsibility as to the content of the files contained in the ZIP file
"IEC61850_HTML.zip" (html, xml and jpg) or the "browsable" pdf file and linked on this page
respectively.
Karlheinz Schwarz, based in Karlsruhe, Germany, is a consultant for the power systems control
industry. He is involved in several Working Groups within IEC TC 57, TC 65, and TC 88. He is a well-
known authority on the standardization and application of advanced information and communication
technologies.
© IEC 2004
Version 1.1  2004-03-22
SV
SV
SV
SV
What is a Logical Node?
By Karlheinz Schwarz, SCC, [e-mail]
Motivation
The standard IEC 61850 „Communication networks and systems in substations“ and the
coming standard IEC 61400-25 „Communications for monitoring and control of wind power
plants“ use the concept of Logical Nodes (LN) as a key element to define the information of
a device to be communicated. This paper introduces the concept of LNs.
Modeling
A key issue are the LNs representing functions or equipment used in power systems. Each
oncept
LN provides a list of well organized and named information. The LN “XCBR5” represents
the “circuit breaker” number 5 with the data “Pos” (Position) and “Mode”. Services defined
in IEC 61850-7-2 allow the exchange of this information.
logical device (Bay)
IEC 61850-7-2
(Virtual World) virtualisation
Services
IEC 61850
models substation
equipment and func-
LN
TCP/IP
tions (focus is on
LNLN
MMS
LN
Network
protection)
IEC 61400-25 XCBR5
models components
Pos
SCSM
of wind power plants
IEC 61850-8-1
Mode
like rotor, generator,
...
Real
gear box, nacelle etc. devices in a
substation
IEC 61850-7-4 logical
(focus is on SCADA)
IEC 61850-7-4
node (circuit breaker)
data (Position)
IEC 61850-6
configuration file, XML
The substation configuration language in part 6 supports the engineering process.
Example LN
The measurement LN “MMXU” represents power, voltages, currents, and impedances in a
“MMXU”
three-phase system. The values can be communicated by various services

Logical Node „MMXU“
Read
deadbanded value
Read
TotW Total Active Power (Total P)
angle
TotVAr Total Reactive Power (Total Q)

TotVA phsA.cVTotal Appareal nt Power (Total S)
Report
Report RCB
IEC 61850-7-4 RCB
TotPF phsB.cVAverage alPower factor (Total PF)
defines some
Hz phsCFrequency.cVal
90 LNs
PPV Phase to phase voltages (VL1VL2, …)
QueryLog
QueryLog
Log
Log
500 Data PhV Phase to ground voltages (VL1ER, …)
100 Attributes A Phase currents (IL1, IL2, IL3)
10 Service models W Phase active power (P)
Configure
Configure
VAr Phase reactive power (Q)
IEC 61400-25
VA Phase apparent power (S)
Retrieve
adds some
Retrieve
PF Phase power factor
Model
Model
10 LNs
Z Phase Impedance
200 Data
IEC 61850-7-2
100 Attributes
current / voltage samples from instrument
IEC 61850-7-2
transformers represented by LN “PhsBTCTR” for
current transformer of phase B (e.g. by sampled LN PhsBTCTR LN PhsBTVTR
LN PhsBTCTR LN PhsBTVTR
Amp Vol
value exchange services of IEC 61850-7-2 SV) Amp Vol

The “MMXU” LN offers hundreds of values: measured (process) values, configuration val-
ues, description, and substitution values. These values can be communicated by various
services like read (polling), notification (publish/subscribe), logging and query.
© SCC Draft 0-2 2004-01-03
Mapping
ACSI overview and basic concepts
General
The models of the ACSI provide
�   the specification of a basic model for the definition of the substation-specific information models contained
in IEC 61850-7-3 (common DATA classes) and IEC 61850-7-4 (compatible LOGICAL-NODE classes and
compatible DATA classes) and
�   the specification of information exchange service models.
The information models and information exchange services are interwoven. From a descriptive point of view, the
two aspects are separated to some degree (see the excerpt shown in Figure 1). The common models (for
example, LOGICAL-NODE and DATA classes including their services) are applied in IEC 61850-7-3 and IEC
61850-7-4 to define many specialized information models - the substation automation models.
Figure 1 - Excerpt of conceptual model
Other service models required for substation automation systems (for example, DATA-SET and reporting provide
specific information exchange services) are also defined in this part of the standard; these models are linked to
LOGICAL-NODEs and DATA. The information exchange services are completely defined in the ACSI. The
information models defined in IEC 61850-7-4 reference the services defined in the various models of the ACSI.
Overview of basic information models
The conceptual models to build the domain-specific information models are:
�   SERVER - represents the external visible behaviour of a device. All other ACSI models are part of the
server.
NOTE 1 A server has two roles: to communicate with a client (most service models in IEC 61850 provide
communication with client devices) and to send information to peer devices (for example, for sampled
values).
�   LOGICAL-DEVICE (LD) - contains the information produced and consumed by a group of domain-specific
application functions; functions are defined as LOGICAL-NODEs.
�   LOGICAL-NODE (LN) - contains the information produced and consumed by a domain-specific application
function, for example, overvoltage protection or circuit-breaker.
�   DATA - provide means to specify typed information, for example, position of a switch with quality
information and timestamp, contained in LOGICAL-NODEs.

Each of these information models is defined as a class. The classes comprise attributes and services. The
conceptual class diagram of the ACSI is depicted in Figure 2.
NOTE 2 The classes are major building blocks that provide the framework for substation automation device
models. Additional details on the modelling and relations between IEC 61850-7-4, IEC 61850-7-3, and this part of
IEC 61850 can be found in IEC 61850-7-1.
Click on boxes to get the definitions!
Figure 2 - Basic conceptual class model of the ACSI
Click on boxes to get the definitions!
NOTE 3 The numbers in the circles indicate the respective clauses in this part of IEC 61850.
The Name class is inherited by the classes LOGICAL-DEVICE, LOGICAL-NODE, DATA, and DataAttribute.
EXAMPLE In an implementation the logical device, logical node, data, and data attribute have each an object
name (instance name) which is a unique name among classes of the same container to which they belong. In
addition, each of the four has an ObjectReference (path name) which is a concatenation of all object names from
each container. The four object names (one per column) can be concatenated.
Logical device Logical node Data Data attribute
Object name "Atlanta_HV5" "XCBR1" "Pos" "stVal"

Description
High-voltage station 5 Circuit-breaker 1 Position Status value
Overview of the other service models
In addition to the models listed above, the ACSI comprises the following models that provide services operating
on data, data attributes, and data sets.
�   DATA-SET - permits the grouping of data and data attributes. Used for direct access and for reporting and
logging.
�   Substitution - supports replacement of a process value by another value.
�   SETTING-GROUP-CONTROL-BLOCK - defines how to switch from one set of setting values to another
one and how to edit setting groups.
�   REPORT-CONTROL-BLOCK and LOG-CONTROL-BLOCK - describe the conditions for generating
reports and logs based on parameters set by the client. Reports may be triggered by changes of process
data values (for example, state change or dead band) or by quality changes. Logs can be queried for later
retrieval. Reports may be sent immediately or deferred. Reports provide change-of-state and sequence-of-
events information exchange.
�   control blocks for generic substation event (GSE) - supports a fast and reliable system-wide distribution of
input and output data values; peer-to-peer exchange of IED binary status information, for example, a trip
signal.
�   control blocks for transmission of sampled values - fast and cyclic transfer of samples, for example, of
instrument transformers.
�   control - describes the services to control, for example, devices.
�   time and time synchronization - provides the time base for the device and system.
�   file transfer - defines the exchange of large data blocks such as programs.
An overview of the conceptual service model of the ACSI is shown in Figure 3.
Click on boxes to get the definitions!

Figure 3 - Conceptual service model of the ACSI
Click on boxes to get the definitions!
NOTE 1 The numbers in the circles indicate the respective clauses in this part of IEC 61850.
NOTE 2 The class diagrams are conceptual. Details are defined in the respective clauses. Comprehensive
diagrams are contained in IEC 61850-7-1. The DATA class may be defined recursively. The operations for
substitution and control are restricted to the lowest level in the DATA class. The DataAttributes may be defined
recursively as well.
The logical node is one of the major building blocks that has associations to most of the other information
exchange models, for example, report control, log control, and setting control.
Any other information exchange service model, for example, report control, log control, and setting control shall
inherit the ObjectName and ObjectReference as depicted in Figure 2.
NOTE 3 The class models and services are defined using an object-oriented approach allowing for the mapping

of class models and services to different application layer and middle ware solutions.
Overview of ACSI services
The complete list of ACSI classes and their services is shown in Table 1.
Table 1 - ACSI classes
SERVER model (Clause 6) LOG-CONTROL-BLOCK model:
GetServerDirectory GetLCBValues
SetLCBValues
QueryLogByTime
ASSOCIATION model (Clause 7)
QueryLogAfter
Associate
GetLogStatusValues
Abort
Release
Generic substation event model —
GSE (Clause 15)
LOGICAL-DEVICE model (Clause 8)
GOOSE
GetLogicalDeviceDirectory
SendGOOSEMessage
GetGoReference
LOGICAL-NODE model (Clause 9)
GetGOOSEElementNumber
GetLogicalNodeDirectory
GetGoCBValues
GetAllDataValues
SetGoCBValues
GSSE
DATA model (Clause 10)
SendGSSEMessage
GetDataValues
GetGsReference
SetDataValues
GetGSSEDataOffset
GetDataDirectory
GetGsCBValues
GetDataDefinition
SetGsCBValues
DATA-SET model (Clause 11)
Transmission of sampled values model
GetDataSetValues
(Clause 16)
SetDataSetValues
MULTICAST-SAMPLE-VALUE-CONTROL-BLOCK:
CreateDataSet
SendMSVMessage
DeleteDataSet
GetMSVCBValues
GetDataSetDirectory
SetMSVCBValues
UNICAST-SAMPLE-VALUE-CONTROL-BLOCK:
Substitution model (Clause 12)
SetDataValues SendUSVMessage
GetUSVCBValues
GetDataValues
SetUSVCBValues
SETTING-GROUP-CONTROL-BLOCK model
Control model (Clause 17)
(Clause 13)
Select
SelectActiveSG
SelectWithValue
SelectEditSG
Cancel
SetSGValues
Operate
ConfirmEditSGValues
CommandTermination
GetSGValues
TimeActivatedOperate
GetSGCBValues
Time and time synchronization (Clause 18)
TimeSynchronization
REPORT-CONTROL-BLOCK and LOG-
CONTROL-BLOCK model (Clause 14) FILE transfer model (Clause 20)
BUFFERED-REPORT-CONTROL-BLOCK: GetFile
SetFile
Report
DeleteFile
GetBRCBValues
GetFileAttributeValues
SetBRCBValues
UNBUFF
...