IEC 61968-13:2008

Application integration at electric utilities - System interfaces for distribution management - Part 13: CIM RDF Model exchange format for distribution

IEC 61968-13:2008 specifies the format and rules for exchanging modelling information based upon the Common Information Model ("CIM") and related to distribution network data. Allows the exchange of instance data in bulk. Thus, the imported network model data should be sufficient to allow performing network connectivity analysis, including network tracing, outage analysis, load flow calculations, etc. This standard could be used for synchronizing geographical information system databases with remote control system databases.

Intégration d'applications pour les services électriques - Interfaces systèmes pour la gestion de la distribution - Partie 13: Format d'échange du modèle CIM RDF pour la distribution

La CEI 61968-13:2008 spécifie le format et les règles pour l'échange d'informations de modélisation sur la base du CIM (Common Information Model) et en rapport avec des données de réseau de distribution. Permet l'échange de données d'instance en masse. Ainsi, il convient que les données de modèles de réseau importées soient suffisantes pour permettre d'accomplir l'analyse de connectivité de réseau, y compris le suivi de réseau, l'analyse d'interruptions de service, les calculs de flux de charge, etc. La présente partie pourrait être utilisée pour synchroniser des bases de données de systèmes d'informations géographiques avec des bases de données de systèmes de conduite à distance.

General Information

• Status: Published
• Publication Date: 23-Jun-2008
• ICS: 33.200 - Telecontrol. Telemetering
• Technical Committee: TC 57 - Power systems management and associated information exchange
• Drafting Committee: WG 14 - TC 57/WG 14
• Current Stage: DELPUB - Deleted Publication
• Start Date: 16-Mar-2021
• Completion Date: 26-Oct-2025

Relations

• Revised: IEC 61968-13:2021 - Application integration at electric utilities - System interfaces for distribution management - Part 13: Common distribution power system model profiles
• Effective Date: 05-Sep-2023

Overview

IEC 61968-13:2008 specifies the CIM RDF model exchange format for distribution. It defines the XML/RDF syntax and rules for exchanging bulk instance data based on the Common Information Model (CIM) to represent distribution network models. The exported CIM XML model contains enough detail to support network connectivity analysis (network tracing), outage analysis, load flow calculations and to synchronize Geographic Information Systems (GIS) with remote control/DMS databases. The standard is part of the IEC 61968 series for application integration at electric utilities and aligns with CIM model version 11 (CPSM 3.0 profile).

Key topics and requirements

• CIM RDF/CIM XML format: Uses the CIM RDF schema defined in IEC 61970-501 as the meta-model for constructing interoperable XML documents.
• Bulk instance exchange: Supports file-based model exchange to import/export complete distribution network models.
• Completeness for analysis: Exported data must enable connectivity and power system analyses (tracing, outage and load flow).
• Profiles/subsets: Defines CIM subsets (profiles) tailored for distribution use to address specific exchange needs.
• Device and topology modelling: Covers classes and mappings for distribution objects such as BaseVoltage, VoltageLevel, BusbarSection, PowerTransformer, ACLineSegment, WireArrangement, Switch, Compensator, StaticVarCompensator, EquivalentLoad, GeneratingUnit and SynchronousMachine.
• Partial-phase / unbalanced modelling: Addresses issues for partial-phase devices, impedances in unbalanced systems and switch/phase continuity semantics.
• Interoperability guidance: Style and serialization rules to ensure consistent RDF/XML documents across systems.
• Examples and annexes: Includes example European and North American distribution network datasets and comparisons with CIM XSD.

Applications and users

Who benefits:

• Utility integration architects implementing inter-application integration between DMS, SCADA, OMS and GIS.
• Systems integrators and software vendors exchanging full network models between heterogeneous systems.
• GIS and remote control/SCADA teams synchronizing network topology and asset data.
• Power system analysts who require consistent model imports for tracing, outage simulation and load flow.
• Smart grid and DER integrators modeling distributed energy resources with CIM-compatible tools.

Practical uses:

• Bulk import/export of distribution network models during system upgrades or vendor replacements.
• Synchronizing GIS with DMS/SCADA to maintain a single authoritative network model.
• Sharing network models between utilities, vendors and consultancy tools for studies and operational planning.

Related standards

• IEC 61968 series (system interfaces for distribution management)
• IEC 61970-452 (EMS-API CIM network model exchange specification)
• IEC 61970-501 (CIM RDF schema reference)
• RDF / XML / Common Information Model (CIM) concepts

Keywords: IEC 61968-13, CIM RDF, CIM XML, distribution model exchange, DMS integration, GIS synchronization, network connectivity analysis, load flow, outage analysis.

Standards Content (Sample)

IEC 61968-13
Edition 1.0 2008-06
INTERNATIONAL
STANDARD
Application integration at electric utilities – System interfaces for distribution
management –
Part 13: CIM RDF Model exchange format for distribution

All rights reserved. Unless otherwise specified, 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
either IEC or IEC's member National Committee in the country of the requester.
If you have any questions about IEC copyright or have an enquiry about obtaining additional rights to this publication,

please contact the address below or your local IEC member National Committee for further information.

IEC Central Office
3, rue de Varembé
CH-1211 Geneva 20
Switzerland
Email: [e-mail]
Web: www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.
ƒ Catalogue of IEC publications: www.iec.ch/searchpub
The IEC on-line Catalogue enables you to search by a variety of criteria (reference number, text, technical committee,…).
It also gives information on projects, withdrawn and replaced publications.
ƒ IEC Just Published: www.iec.ch/online_news/justpub
Stay up to date on all new IEC publications. Just Published details twice a month all new publications released. Available
on-line and also by email.
ƒ Electropedia: www.electropedia.org
The world's leading online dictionary of electronic and electrical terms containing more than 20 000 terms and definitions
in English and French, with equivalent terms in additional languages. Also known as the International Electrotechnical
Vocabulary online.
ƒ Customer Service Centre: www.iec.ch/webstore/custserv
If you wish to give us your feedback on this publication or need further assistance, please visit the Customer Service
Centre FAQ or contact us:
Email: [e-mail]
Tel.: [phone]
Fax: [phone]
IEC 61968-13
Edition 1.0 2008-06
INTERNATIONAL
STANDARD
Application integration at electric utilities – System interfaces for distribution
management –
Part 13: CIM RDF Model exchange format for distribution

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XA
ICS 33.200 ISBN 2-8318-9873-0
– 2 – 61968-13 © IEC:2008(E)
CONTENTS
FOREWORD.4

INTRODUCTION.6

1 Scope.7

2 Normative references .8

3 Future standards documents related to this part .9

4 CIM RDF describing distribution networks .9

5 Issues related to partial-phase devices modeling.10

5.1 General .10
5.2 Impedances of unbalanced and partial phase devices .10
5.3 Switches .10
5.4 Partial phase continuity in radial networks.10
6 CIM classes used and corresponding RDF .11
6.1 General .11
6.2 BaseVoltage and VoltageLevel .11
6.3 Containment hierarchy roots.12
6.4 HV/MV substation.12
6.5 MV/MV substation .12
6.6 MV/LV substation .13
6.7 Junction .13
)
6.8 Switch .14
6.9 Bay .14
6.10 BusbarSection.15
6.11 PowerTransformer.16
6.12 MV/MV transformer .17
6.13 Line.17
6.14 ACLineSegment .19
6.15 WireArrangement .19
6.16 Compensator.21
6.17 StaticVarCompensator.21
6.18 EquivalentLoad .22
6.19 Using CustomerLoad, GeneratingUnit and SynchronousMachine to model
Distributed Energy Resource .23

6.20 GeneratingUnit .24
6.21 SynchronousMachine .24
6.22 HostControlArea.25
6.23 SubControlArea.25
7 Adequation between IEC 61968-3 (CDPSM) and IEC 61968-4.25
8 Adequation between CDPSM and CPSM .26
Annex A (informative) CIM XML Document from Langdale .27
Annex B (informative) Comparison between CIM RDF and CIM XSD (ISO ITC
Working Group Architecture).30
Annex C (informative) Key discussion points on CIM RDF and CIM XSD (ISO ITC
Working Group Architecture).
Annex D (informative) Conclusions and recommendations (ISO ITC Working Group
Architecture) .33

61968-13 © IEC:2008(E) – 3 –
Annex E (informative) Example of a European distribution network described through

CIM RDF.34

Annex F (informative) Example of a North American distribution network .42

Annex G (informative) Comparison between CDPSM and CPSM.44

Bibliography.58

Figure 1 – XML-based DMS network data configuration .8

Figure 2 – Connectivity of BusbarSection.15

Figure E.1 – European distribution network example.35

Figure F.1 – North American distribution network example.43

Table 1 – Header of NetworkDataSet message type .25
Table 2 – Message Payload of NetworkDataSet message type .26

– 4 – 61968-13 © IEC:2008(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION

______________
APPLICATION INTEGRATION AT ELECTRIC UTILITIES –

SYSTEM INTERFACES FOR DISTRIBUTION MANAGEMENT –

Part 13: CIM RDF Model exchange format for distribution

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61968-13 has been prepared by IEC technical committee 57:
Power systems management and associated information exchange.
The text of this standard is based on the following documents:
FDIS Report on Voting
57/930/FDIS 57/955/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
A list of all parts of the IEC 61968 series, under the general title Application integration at
electric utilities – System interfaces for distribution management, can be found on the IEC
website.
61968-13 © IEC:2008(E) – 5 –
The committee has decided that the contents of this publication will remain unchanged until

the maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in

the data related to the specific publication. At this date, the publication will be

• reconfirmed;
• withdrawn;
• replaced by a revised edition, or

• amended.
A bilingual version of this publication may be issued at a later date.

– 6 – 61968-13 © IEC:2008(E)
INTRODUCTION
The IEC 61968 series of standards is intended to facilitate inter-application integration as

opposed to intra-application integration. Intra-application integration is aimed at programs in

the same application system, usually communicating with each other using middleware that is

embedded in their underlying runtime environment, and tends to be optimized for close, real-

time, synchronous connections and interactive request/reply or conversation communication

models. IEC 61968, by contrast, is intended to support the inter-application integration of a

utility enterprise that needs to connect disparate applications that are already built or new

(legacy or purchased applications), each supported by dissimilar runtime environments.

Therefore, these interface standards are relevant to loosely coupled applications with more

heterogeneity in languages, operating systems, protocols and management tools. This series
of standards is intended to support applications that need to exchange data every few
seconds, minutes, or hours rather than waiting for a nightly batch run. This series of
standards, which are intended to be implemented with middleware services that exchange
messages among applications, will complement, not replace utility data warehouses,
database gateways, and operational stores.
As used in IEC 61968, a DMS consists of various distributed application components for the
utility to manage electrical distribution networks. These capabilities include monitoring and
control of equipment for power delivery, management processes to ensure system reliability,
voltage management, demand-side management, outage management, work management,
automated mapping and facilities management. Standards interfaces are defined for each
class of applications identified in the Interface Reference Model (IRM), which is described in
IEC 61968-1.
61968-13 © IEC:2008(E) – 7 –
APPLICATION INTEGRATION AT ELECTRIC UTILITIES –

SYSTEM INTERFACES FOR DISTRIBUTION MANAGEMENT –

Part 13: CIM RDF Model exchange format for distribution

1 Scope
This part of IEC 61968 specifies the format and rules for exchanging modeling information
based upon the CIM (Common Information Model) and related to distribution network data.
The intention of this part of IEC 61968 is to allow the exchange of instance data in bulk. Thus,
the imported network model data should be sufficient to allow performing network connectivity
analysis, including network tracing, outage analysis, load flow calculations, etc. This part
could be used for synchronizing geographical information system databases with remote
control system databases.
This part is closely linked to IEC 61970-452 Energy Management System Application Program
Interface (EMS-API) CIM Network applications model exchange specification. Thus, this
document has been written in order to reduce its maintenance. It describes only differences
with IEC 61970-452. Nevertheless, as IEC 61970-452 is a future international standard, this
part still has duplicate information with IEC 61970-452, in order to be more understandable.
)
It uses the CIM RDF Schema presented in IEC 61970-501 as the meta-model framework for
)
constructing XML documents containing power system modeling information. The syntax of
these documents is called CIM XML format. Model exchange by file transfer serves many
useful purposes, specially when some applications need to have the complete network model
defined. Though the format can be used for general CIM-based information exchange, in this
part of IEC 61968, specific profiles (or subsets) of the CIM are identified in order to address
particular exchange requirements.
Given the CIM RDF Schema described in IEC 61970-501, a DMS power system model can be
converted for export as an XML document, see Figure 1. This document is referred to as a
CIM XML document. All of the tags (resource descriptions) used in the CIM XML document
are supplied by the CIM RDF schema. The resulting CIM XML model exchange document can
be parsed and the information imported into a foreign system. This part of IEC 61968 is
aligned to CIM Model version 11, CPSM 3.0 profile.

———————
)
RDF: Resource Description Framework.
)
XML: eXtensible Markup Language.

– 8 – 61968-13 © IEC:2008(E)
IEC 61968-13
CIM in UML
Profile based on
IEC 61970-452 (CIM
Transmission
IEC 61968 Parts 3 -10
Network applications
(IEC 61970-301)
CIM/XSD Messages
model exchange
System A
System B
specification)
Proprietary
Proprietary
Distribution
network model
network model
(IEC 61968-11)
IEC 61970-501
CIM RDF schema
Import/export
Import/export
IEC 61970-552-4
process
process
CIM XML model
exchange format
IEC 61968
IEC 61968
network model
network model
CIM/XML
WC3 RDF Syntax CIM/XML
document
document
IEC  940/08
Figure 1 – XML-based DMS network data configuration
Similar to using any programming language, implementers have many choices when creating
a CIM XML document. The RDF syntax itself can be used in several ways to achieve the
same basic result. The way one approaches the CIM RDF Schema can yield various forms
when producing a CIM XML document. The following clauses discuss the style guidelines for
producing a CIM XML document. Such guideline rules are important to communicate and
follow when producing these documents because they simplify and facilitate the software
written to unambiguously interpret the model information.
Some comparisons have been made between CIM RDF and CIM XSD. Annexes A, B, C and D
are extracted from articles and documents discussing CIM RDF and CIM XSD. A distribution
management system can use only a CIM XSD message types architecture, but CIM RDF has
three advantages:
• A UML model is a graph model and RDF helps to describe the graph model. XSD
describes a hierarchical model which suits the message type approach.
• RDF is more readable and understandable by people working in the electrotechnical field.
• It is a basic requirement to build ontologies.
If required, tools would ensure the compatibility between CIM-RDF and, for instance,
IEC 61968-4 and IEC 61968-3 message types concerning distribution network model
representation.
2 Normative references
The following referenced documents are indispensable for the application of this document.
For dated references, only the edition cited applies. For undated references, the latest edition
of the referenced document (including any amendments) applies.
IEC 61968-1, Application integration at electric utilities – System interfaces for distribution
management – Part 1: Interface architecture and general requirements
IEC 61968-3, Application integration at electric utilities – System interfaces for distribution
management – Part 3: Interface for network operations
IEC 61968-4, Application integration at electric utilities – System interfaces for distribution
management – Part 4: Interfaces for records and asset management

61968-13 © IEC:2008(E) – 9 –
IEC 61970-301, Energy management system application program interface (EMS-API) – Part

301: Common Information Model (CIM) base

IEC 61970-501, Energy management system application program interface (EMS-API) – Part

501: Common Information Model Resource Description Framework (CIM RDF) schema

3 Future standards documents related to this part

The following documents are taken into account even if they have not been published as FDIS

yet.
Extensions to CIM for Distribution: IEC 61968-11.
This document is used during interoperability tests: IEC 61970-452.
IEC 61970-552-4, EMS-API – Part 552-4: CIM XML Model Exchange Format.
4 CIM RDF describing distribution networks
In this part of the IEC 61968 standard, the object is to describe a CIM RDF model for the
Distribution networks. It has the same objective as the NERC Common Power System Model
(CPSM) Profile that has been agreed to at the Transmission level (reference:
http://www.w3.org/TR/2004/REC-rdf-primer-20040210 subclause 6.5, and IEC 61970-452). At
the distribution level, several kinds of application exist such as Network Operation, Asset
Management, Customer Information, Network Planning, Work Management, etc. Efforts on
standardization of these applications are conducted at the IEC through the Technical
Committee 57. For more information, refer to http://www.cimuser.org web site.
Electric utilities use power system models for a number of different purposes. For example,
power system simulations are developed for planning and security analysis. An operational
power system model may consist of thousands of classes of information. In addition to using
these models in-house, applications inside an individual utility need to exchange system
modelling information, both for planning and operational purposes (e.g. coordinating
transmission and distribution networks and ensuring reliable operations). However, individual
utilities use different software packages for these purposes. As a result, the system models
are stored in different formats, making exchange among these models difficult. The exchange
of model data is difficult and requires specific interface development for data exchange
between each pair of applications. Consequently, the individual utilities recognize the need to
agree on common definitions of the power system entities and relationships to facilitate the
future data exchange requirements.

The CIM defines most of objects inside an electric utility as classes and attributes, as well as
the relationships among them. The CIM uses these object classes, their attributes and
relationships to support the integration of independently developed applications among
vendor specific DMS applications. CIM represents a canonical data model to support data
exchange between each part of a DMS system such as asset management, distribution
planning, etc.
Based on the NERC CPSM Profile for the transmission network, this part of IEC 61968
proposes a CIM-RDF profile for modelling Distribution networks. This part of IEC 61968
defines a CDPSM profile (Common Distribution Power System Model). IEC 61968-13 will
mention the differences between this part of IEC 61968 and CPSM profile when they occur.
The data intended for initial configuration of distribution network applications includes the
applications such as distribution load flow calculation, dynamic network coloring, stability
studies due to the impact of Distributed Energy Resources on Distribution Networks,

– 10 – 61968-13 © IEC:2008(E)
Distribution remote control system data management, exchange of data between TSO

(Transmission System Operator) and DSO (Distribution System Operator), etc.

Consequently, the proposal is mainly based on IEC 61970-301, without, at the present time,

the Asset classes found in IEC 61968-11. In the future, assetType attribute of Asset class will

be used instead of PsrType if CIM IEC 61968-11 is normalized and incorporated officially in

the CIM. In this part of IEC 61968, class Location is defined in the IEC 61968-11 packages.

This part of IEC 61968 is valid for three-phase balanced and unbalanced distribution

networks. It is described as a single phase network and may have single- or two-phase

)
components such as single-phase laterals and transformers . However, some users may find

it convenient to restrict the proposed profile to include only the subset of three-phase
balanced networks and exclude support for single phase components. In the Clauses which
follow, the term “partial-phase devices” is used to describe components having less than three
phases.
5 Issues related to partial-phase devices modeling
5.1 General
The IEC 61970-301 standard already has support for partial phase conducting devices
through the phase-code attribute which may be a combination of any or all of the letters A, B,
C, and N. In general, one can think of a partial phase conducting device as being the same as
a full 3-phase device with some of the phases missing.
5.2 Impedances of unbalanced and partial phase devices
IEC 61970-301 specifies impedance of conducting devices in terms of the real and reactive
positive and zero sequence impedance. Unfortunately, this is only valid for perfectly
symmetric three-phase networks where all 3 phases have the same value of self-impedance
and the same mutual impedance value.
The impedance of unbalanced 3-phase conducting devices such as AC line segments shall be
specified as a three by three complex matrix where the diagonal terms specify the self
impedance of each phase and the off-diagonal terms specify the mutual impedance between
each phase pair. These values can be computed using Carson’s equations based on the
geometric mean radius, the linear resistance and the geometric arrangement of the three
phases on the pole. IEC 61970-301 provides all the parameters necessary in the Conductor
and WireArrangement classes. For 2-phase devices, the impedance matrix is two by two and
for single-phase devices, it is a complex scalar specifying the self impedance of the single
phase conductor.
5.3 Switches
IEC 61970-301 allows only two states for a switch device, i.e. open and closed. Thus for a 3-
phase switch, it suggests that all three phases of the switch always operate together and it
does not support the situation where, for example, phase A of the switch is open while phases
B and C are closed. Of course, a single-phase switch may be open or closed.
5.4 Partial phase continuity in radial networks
Many distribution networks are operated radially, meaning that there is only one path for
power to be supplied to any conducting device. For all phases of a device in a radial network
to be properly energized, all devices upstream shall have the same phases present. (For
———————
)
The USA radial electric distribution system is typically unbalanced. The main distribution feeder is three-phased
with single-phased tapped load. The model exchange format should support a three-phased, unbalanced model
to support, as an example, unbalanced load flow calculations.

61968-13 © IEC:2008(E) – 11 –
example, it is not possible to energize all the phases of a three phase device via a partial

phase upstream device.)
However, this requirement is not enforced in this part of IEC 61968. Rather, it is up to the

importing DMS to check if this requirement is satisfied throughout the network.

6 CIM classes used and corresponding RDF

6.1 General
There is a large variety of voltage combinations in a substation. In addition, substations may

generally contain one, two or more voltage levels. The applications needing such “substation
type” information will deduce the substation type from the voltage levels it contains.
In general, substations may contain one, two or more voltage levels, the substation type will
be deduced by analyzing the voltage levels a substation contains. The class PSRType can be
used to distinguish these different substations. Class Location can be used to define the
absolute position of a Substation.
Annex E gives a complete example of a Distribution Network Data represented through CIM-
RDF. It should be pointed out that this complete example has been successfully tested during
CIM interoperability tests conducted by EPRI in 2004, 2005, and 2006.
From the standpoint of a data producer (exporter), the document describes a minimum subset
of CIM classes and class data which must be present in an XML formatted data file to comply
with CDPSM Minimum Data Requirements. From the standpoint of a data recipient (importer),
the document describes a subset of the CIM that an importer could reasonably expect to
receive in an XML data file designed to be compliant with the CDPSM Minimum Data
Requirements (see IEC 61970-501).
6.2 BaseVoltage and VoltageLevel
For every operating voltage found in the network, a BaseVoltage is created. An
ACLineSegment is associated to a BaseVoltage. A TransformerWinding is associated to a
BaseVoltage. PowerTransformer should be contained in a Substation.
Every Substation is associated with one or more VoltageLevel-s, each of which is in turn
associated with the corresponding BaseVoltage.
All the objects of the network, except ACLineSegment, PowerTransformer and Transformer
Winding should be contained within a VoltageLevel.

– 12 – 61968-13 © IEC:2008(E)


63


42




NOD10S61






NOD10S62



6.3 Containment hierarchy roots
The CPSM 2.0 profile of base CIM defines HostControlArea to be at the root of containment
hierarchy. In contrast, this specification defines HV/MV Substation as the root of the
containment hierarchy.
6.4 HV/MV substation
The containment hierarchy begins by HV/MV Substation.

AIGUE_HVMV



HV/MV Substation





910700
66270


6.5 MV/MV substation

AIGUE_MVMV



MV/MV Substation






910700
66270


61968-13 © IEC:2008(E) – 13 –
6.6 MV/LV substation

AIGUE_MVLV





MV/LV Substation








910700
66270


If HV/LV Substation and LV/LV Substation have to be modeled, they will follow the same
principles as above.
In IEC 61968-13, all conducting equipment shall be a member of either a substation or of a
feeder. Normally, all substation equipment is housed in a physical enclosure such as a
building or a fenced area. A feeder is generally outside a physical enclosure and consists of a
collection, or connected set, of AC line segments, switches, transformers (which may or may
not be considered as a substation), etc. See further discussion of the feeder container object
under “Line” later in this document.
In addition, IEC 61968-13 shall support generalized equipment containers to group a set of
connected conducting devices – for example the CompositeSwitch device of IEC 61970-301.
6.7 Junction
In the CIM, devices are connected to each other by connecting a terminal of a device to a
common ConnectivityNode. A connectivity node may have any number of terminals connected
to it.
In a Distribution network, most ConnectivityNodes are contained in substations. However, in
some cases (e.g. a tapped distribution line), ConnectivityNodes may be located on lines which
are outside of substations. IEC 61970-301 defines the Junction class to indicate such
connectivity nodes. In this case, the ConnectivityNode and the Junction shall be located in a
virtual Substation.
However, a typical distribution network generally has many connectivity nodes outside of

substations along a feeder. Since these connectivity nodes serve no purpose other than to
connect two or more devices, it is generally not necessary to also specify them as a Junction.

– 14 – 61968-13 © IEC:2008(E)
)
6.8 Switch
Switches are contained either by VoltageLevel or by Bay. If Switches are contained by

VoltageLevel, Bay is not required. The abstract Switch is used only when we do not know the

detailed class.
IEC 61968-13 supports the following kinds of Switch devices:

Breaker (exists in CPSM): able to interrupt fault currents greater than normal load currents.

LoadBreakSwitch (exists in CPSM): able to interrupt normal load currents only.

Disconnector (exists in CPSM): no current interrupt capability.
Fuse (does not exist in CPSM): able to interrupt fault currents.
Jumper (does not exist in CPSM).
GroundDisconnector (does not exist in CPSM).


63


NOD10S61




AIGUE_HVMV



73109J0001
false






909255.1
56999


6.9 Bay
IEC 61970-301 supports the Bay object as a collection or container of a set of switch devices
and connectivity nodes inside a substation. Generally, a substation will contain several,
usually identical, bays containing connectivity nodes for incoming or outgoing lines (feeders)
Outgoing and incoming feeders are distinguished by the class PSRType. (PSRType and
Location are not mandatory).
———————
)
This should be forbidden, as switch is an abstract class.

61968-13 © IEC:2008(E) – 15 –
This data is not mandatory. If Switches are contained by VoltageLevel, Bay is not required.



63


NOD10S61






AIGUE_HVMV




AIGUEC0601




OUTGOING FEEDER


AIGUEC0601
false






910696
66272


6.10 BusbarSection
Figure 2 describes the connectivity of a BusbarSection which has only one Terminal.
Terminal
BusbarSection
ConnectivityNode
IEC  941/08
Figure 2 – Connectivity of BusbarSection

– 16 – 61968-13 © IEC:2008(E)


63


NOD10S61






AIGUE_HVMV




AIGUEB0001













910720
66290


6.11 PowerTransformer
IEC 61968-13 supports transformer objects and their tap changers exactly as defined in
IEC 61970-301.
While an Autotransformer in reality does not have two distinct windings, it is acceptable in
IEC 61968-13 to model it as having two windings similar to conventional transformers in order
to define the voltage ratio. However, in distribution systems, line voltage regulators are
sometimes used to compensate for line voltage drop. Line voltage regulators frequently are
Autotransformers which have a nominal 1:1 voltage ratio, but generally operate at slightly off-
nominal taps to provide a voltage boost. There is a special problem defining the leakage
impedance of such devices since at nominal tap position, the leakage impedance is
essentially zero. Therefore for autotransformers with a nominal 1:1 voltage ratio, the leakage

impedance shall be defined with the tap at maximum tap position.
There are dozens of distribution transformer winding configurations which cannot be simply
transformed into Y-Y equivalents as is commonly done for balanced transmission modeling.
Therefore, more information is needed than is provided below in order to accurately model
many transformer types. However, comprehensive transformer modeling would push the size
and detail of the profile beyond practical usability. Depending on the need, Kersting IEEE
models could be used as a guide to an appropriate level of transformer detail to extend this
profile.
The associations for PowerTransformer containment are:
Substation -> PowerTransformer -> TransformerWinding

61968-13 © IEC:2008(E) – 17 –
The TransformerWinding -> BaseVoltage link should be used. The model needs only

BaseVoltage instances that correspond to TransformerWinding’s voltage levels.


42




20


AIGUEY0001







42
20
0.068
1.89
29
22


...

IEC 61968-13 ®
Edition 1.0 2008-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Application integration at electric utilities – System interfaces for distribution
management –
Part 13: CIM RDF Model exchange format for distribution

Intégration d'applications pour les services électriques – Interfaces système
pour la gestion de la distribution –
Partie 13: Format d'échange du modèle CIM RDF pour la distribution

All rights reserved. Unless otherwise specified, 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 either IEC or
IEC's member National Committee in the country of the requester.
If you have any questions about IEC copyright or have an enquiry about obtaining additional rights to this publication,
please contact the address below or your local IEC member National Committee for further information.

Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite
ni utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie
et les microfilms, sans l'accord écrit de la CEI ou du Comité national de la CEI du pays du demandeur.
Si vous avez des questions sur le copyright de la CEI ou si vous désirez obtenir des droits supplémentaires sur cette
publication, utilisez les coordonnées ci-après ou contactez le Comité national de la CEI de votre pays de résidence.

IEC Central Office
3, rue de Varembé
CH-1211 Geneva 20
Switzerland
Email: [e-mail]
Web: www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.
 Catalogue of IEC publications: www.iec.ch/searchpub
The IEC on-line Catalogue enables you to search by a variety of criteria (reference number, text, technical committee,…).
It also gives information on projects, withdrawn and replaced publications.
 IEC Just Published: www.iec.ch/online_news/justpub
Stay up to date on all new IEC publications. Just Published details twice a month all new publications released. Available
on-line and also by email.
 Electropedia: www.electropedia.org
The world's leading online dictionary of electronic and electrical terms containing more than 20 000 terms and definitions
in English and French, with equivalent terms in additional languages. Also known as the International Electrotechnical
Vocabulary online.
 Customer Service Centre: www.iec.ch/webstore/custserv
If you wish to give us your feedback on this publication or need further assistance, please visit the Customer Service
Centre FAQ or contact us:
Email: [e-mail]
Tel.: [phone]
Fax: [phone]
A propos de la CEI
La Commission Electrotechnique Internationale (CEI) est la première organisation mondiale qui élabore et publie des
normes internationales pour tout ce qui a trait à l'électricité, à l'électronique et aux technologies apparentées.

A propos des publications CEI
Le contenu technique des publications de la CEI est constamment revu. Veuillez vous assurer que vous possédez
l’édition la plus récente, un corrigendum ou amendement peut avoir été publié.
 Catalogue des publications de la CEI: www.iec.ch/searchpub/cur_fut-f.htm
Le Catalogue en-ligne de la CEI vous permet d’effectuer des recherches en utilisant différents critères (numéro de référence,
texte, comité d’études,…). Il donne aussi des informations sur les projets et les publications retirées ou remplacées.
 Just Published CEI: www.iec.ch/online_news/justpub
Restez informé sur les nouvelles publications de la CEI. Just Published détaille deux fois par mois les nouvelles
publications parues. Disponible en-ligne et aussi par email.
 Electropedia: www.electropedia.org
Le premier dictionnaire en ligne au monde de termes électroniques et électriques. Il contient plus de 20 000 termes et
définitions en anglais et en français, ainsi que les termes équivalents dans les langues additionnelles. Egalement appelé
Vocabulaire Electrotechnique International en ligne.
 Service Clients: www.iec.ch/webstore/custserv/custserv_entry-f.htm
Si vous désirez nous donner des commentaires sur cette publication ou si vous avez des questions, visitez le FAQ du
Service clients ou contactez-nous:
Email: [e-mail]
Tél.: [phone]
Fax: [phone]
IEC 61968-13 ®
Edition 1.0 2008-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Application integration at electric utilities – System interfaces for distribution
management –
Part 13: CIM RDF Model exchange format for distribution

Intégration d'applications pour les services électriques – Interfaces système
pour la gestion de la distribution –
Partie 13: Format d'échange du modèle CIM RDF pour la distribution

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX XA
ICS 33.200 ISBN 978-2-88912-886-0

– 2 – 61968-13  IEC:2008
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 8
3 Future standards documents related to this part . 9
4 CIM RDF describing distribution networks . 9
5 Issues related to partial-phase devices modeling . 10
5.1 General . 10
5.2 Impedances of unbalanced and partial phase devices . 10
5.3 Switches . 10
5.4 Partial phase continuity in radial networks . 10
6 CIM classes used and corresponding RDF . 11
6.1 General . 11
6.2 BaseVoltage and VoltageLevel . 11
6.3 Containment hierarchy roots . 12
6.4 HV/MV substation . 12
6.5 MV/MV substation . 12
6.6 MV/LV substation . 13
6.7 Junction . 13
)
6.8 Switch . 14
6.9 Bay . 14
6.10 BusbarSection . 15
6.11 PowerTransformer . 16
6.12 MV/MV transformer . 17
6.13 Line . 17
6.14 ACLineSegment . 19
6.15 WireArrangement . 19
6.16 Compensator . 21
6.17 StaticVarCompensator. 21
6.18 EquivalentLoad . 22
6.19 Using CustomerLoad, GeneratingUnit and SynchronousMachine to model
Distributed Energy Resource . 23
6.20 GeneratingUnit . 24
6.21 SynchronousMachine . 24
6.22 HostControlArea . 25
6.23 SubControlArea . 25
7 Adequation between IEC 61968-3 (CDPSM) and IEC 61968-4 . 25
8 Adequation between CDPSM and CPSM . 26
Annex A (informative) CIM XML Document from Langdale . 27
Annex B (informative) Comparison between CIM RDF and CIM XSD (ISO ITC
Working Group Architecture) . 30
Annex C (informative) Key discussion points on CIM RDF and CIM XSD (ISO ITC
Working Group Architecture) . 32
Annex D (informative) Conclusions and recommendations (ISO ITC Working Group

Architecture) . 33

61968-13  IEC:2008 – 3 –
Annex E (informative) Example of a European distribution network described through
CIM RDF. 34
Annex F (informative) Example of a North American distribution network . 42
Annex G (informative) Comparison between CDPSM and CPSM. 44
Bibliography . 58

Figure 1 – XML-based DMS network data configuration . 8
Figure 2 – Connectivity of BusbarSection . 15
Figure E.1 – European distribution network example . 35
Figure F.1 – North American distribution network example . 43

Table 1 – Header of NetworkDataSet message type . 25
Table 2 – Message Payload of NetworkDataSet message type . 26

– 4 – 61968-13  IEC:2008
INTERNATIONAL ELECTROTECHNICAL COMMISSION
______________
APPLICATION INTEGRATION AT ELECTRIC UTILITIES –
SYSTEM INTERFACES FOR DISTRIBUTION MANAGEMENT –

Part 13: CIM RDF Model exchange format for distribution

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61968-13 has been prepared by IEC technical committee 57:
Power systems management and associated information exchange.
This bilingual version (2013-01) corresponds to the monolingual English version, published in
2008-06.
The text of this standard is based on the following documents:
FDIS Report on Voting
57/930/FDIS 57/955/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
The French version of this standard has not been voted upon.

61968-13  IEC:2008 – 5 –
A list of all parts of the IEC 61968 series, under the general title Application integration at
electric utilities – System interfaces for distribution management, can be found on the IEC
website.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in
the data related to the specific publication. At this date, the publication will be
• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
– 6 – 61968-13  IEC:2008
INTRODUCTION
The IEC 61968 series of standards is intended to facilitate inter-application integration as
opposed to intra-application integration. Intra-application integration is aimed at programs in
the same application system, usually communicating with each other using middleware that is
embedded in their underlying runtime environment, and tends to be optimized for close, real-
time, synchronous connections and interactive request/reply or conversation communication
models. IEC 61968, by contrast, is intended to support the inter-application integration of a
utility enterprise that needs to connect disparate applications that are already built or new
(legacy or purchased applications), each supported by dissimilar runtime environments.
Therefore, these interface standards are relevant to loosely coupled applications with more
heterogeneity in languages, operating systems, protocols and management tools. This series
of standards is intended to support applications that need to exchange data every few
seconds, minutes, or hours rather than waiting for a nightly batch run. This series of
standards, which are intended to be implemented with middleware services that exchange
messages among applications, will complement, not replace utility data warehouses,
database gateways, and operational stores.
As used in IEC 61968, a DMS consists of various distributed application components for the
utility to manage electrical distribution networks. These capabilities include monitoring and
control of equipment for power delivery, management processes to ensure system reliability,
voltage management, demand-side management, outage management, work management,
automated mapping and facilities management. Standards interfaces are defined for each
class of applications identified in the Interface Reference Model (IRM), which is described in
IEC 61968-1.
61968-13  IEC:2008 – 7 –
APPLICATION INTEGRATION AT ELECTRIC UTILITIES –
SYSTEM INTERFACES FOR DISTRIBUTION MANAGEMENT –

Part 13: CIM RDF Model exchange format for distribution

1 Scope
This part of IEC 61968 specifies the format and rules for exchanging modeling information
based upon the CIM (Common Information Model) and related to distribution network data.
The intention of this part of IEC 61968 is to allow the exchange of instance data in bulk. Thus,
the imported network model data should be sufficient to allow performing network connectivity
analysis, including network tracing, outage analysis, load flow calculations, etc. This part
could be used for synchronizing geographical information system databases with remote
control system databases.
This part is closely linked to IEC 61970-452 Energy Management System Application Program
Interface (EMS-API) CIM Network applications model exchange specification. Thus, this
document has been written in order to reduce its maintenance. It describes only differences
with IEC 61970-452. Nevertheless, as IEC 61970-452 is a future international standard, this
part still has duplicate information with IEC 61970-452, in order to be more understandable.
)
It uses the CIM RDF Schema presented in IEC 61970-501 as the meta-model framework for
)
constructing XML documents containing power system modeling information. The syntax of
these documents is called CIM XML format. Model exchange by file transfer serves many
useful purposes, specially when some applications need to have the complete network model
defined. Though the format can be used for general CIM-based information exchange, in this
part of IEC 61968, specific profiles (or subsets) of the CIM are identified in order to address
particular exchange requirements.
Given the CIM RDF Schema described in IEC 61970-501, a DMS power system model can be
converted for export as an XML document, see Figure 1. This document is referred to as a
CIM XML document. All of the tags (resource descriptions) used in the CIM XML document
are supplied by the CIM RDF schema. The resulting CIM XML model exchange document can
be parsed and the information imported into a foreign system. This part of IEC 61968 is
aligned to CIM Model version 11, CPSM 3.0 profile.
———————
)
RDF: Resource Description Framework.
)
XML: eXtensible Markup Language.

– 8 – 61968-13  IEC:2008
IEC 61968-13
CIM in UML
Profile based on
IEC 61970-452 (CIM
Transmission
IEC 61968 Parts 3 -10
Network applications
(IEC 61970-301)
CIM/XSD Messages
model exchange
System A
System B
specification)
Proprietary
Proprietary
Distribution
network model
network model
(IEC 61968-11)
IEC 61970-501
CIM RDF schema
Import/export
Import/export
IEC 61970-552-4
process
process
CIM XML model
exchange format
IEC 61968
IEC 61968
network model
network model
CIM/XML
WC3 RDF Syntax CIM/XML
document
document
IEC  940/08
Figure 1 – XML-based DMS network data configuration
Similar to using any programming language, implementers have many choices when creating
a CIM XML document. The RDF syntax itself can be used in several ways to achieve the
same basic result. The way one approaches the CIM RDF Schema can yield various forms
when producing a CIM XML document. The following clauses discuss the style guidelines for
producing a CIM XML document. Such guideline rules are important to communicate and
follow when producing these documents because they simplify and facilitate the software
written to unambiguously interpret the model information.
Some comparisons have been made between CIM RDF and CIM XSD. Annexes A, B, C and D
are extracted from articles and documents discussing CIM RDF and CIM XSD. A distribution
management system can use only a CIM XSD message types architecture, but CIM RDF has
three advantages:
• A UML model is a graph model and RDF helps to describe the graph model. XSD
describes a hierarchical model which suits the message type approach.
• RDF is more readable and understandable by people working in the electrotechnical field.
• It is a basic requirement to build ontologies.
If required, tools would ensure the compatibility between CIM-RDF and, for instance,
IEC 61968-4 and IEC 61968-3 message types concerning distribution network model
representation.
2 Normative references
The following referenced documents are indispensable for the application of this document.
For dated references, only the edition cited applies. For undated references, the latest edition
of the referenced document (including any amendments) applies.
IEC 61968-1, Application integration at electric utilities – System interfaces for distribution
management – Part 1: Interface architecture and general requirements
IEC 61968-3, Application integration at electric utilities – System interfaces for distribution
management – Part 3: Interface for network operations
IEC 61968-4, Application integration at electric utilities – System interfaces for distribution
management – Part 4: Interfaces for records and asset management

61968-13  IEC:2008 – 9 –
IEC 61970-301, Energy management system application program interface (EMS-API) – Part
301: Common Information Model (CIM) base
IEC 61970-501, Energy management system application program interface (EMS-API) – Part
501: Common Information Model Resource Description Framework (CIM RDF) schema
3 Future standards documents related to this part
The following documents are taken into account even if they have not been published as FDIS
yet.
Extensions to CIM for Distribution: IEC 61968-11.
This document is used during interoperability tests: IEC 61970-452.
IEC 61970-552-4, EMS-API – Part 552-4: CIM XML Model Exchange Format.
4 CIM RDF describing distribution networks
In this part of the IEC 61968 standard, the object is to describe a CIM RDF model for the
Distribution networks. It has the same objective as the NERC Common Power System Model
(CPSM) Profile that has been agreed to at the Transmission level (reference:
http://www.w3.org/TR/2004/REC-rdf-primer-20040210 subclause 6.5, and IEC 61970-452). At
the distribution level, several kinds of application exist such as Network Operation, Asset
Management, Customer Information, Network Planning, Work Management, etc. Efforts on
standardization of these applications are conducted at the IEC through the Technical
Committee 57. For more information, refer to http://www.cimuser.org web site.
Electric utilities use power system models for a number of different purposes. For example,
power system simulations are developed for planning and security analysis. An operational
power system model may consist of thousands of classes of information. In addition to using
these models in-house, applications inside an individual utility need to exchange system
modelling information, both for planning and operational purposes (e.g. coordinating
transmission and distribution networks and ensuring reliable operations). However, individual
utilities use different software packages for these purposes. As a result, the system models
are stored in different formats, making exchange among these models difficult. The exchange
of model data is difficult and requires specific interface development for data exchange
between each pair of applications. Consequently, the individual utilities recognize the need to
agree on common definitions of the power system entities and relationships to facilitate the
future data exchange requirements.
The CIM defines most of objects inside an electric utility as classes and attributes, as well as
the relationships among them. The CIM uses these object classes, their attributes and
relationships to support the integration of independently developed applications among
vendor specific DMS applications. CIM represents a canonical data model to support data
exchange between each part of a DMS system such as asset management, distribution
planning, etc.
Based on the NERC CPSM Profile for the transmission network, this part of IEC 61968
proposes a CIM-RDF profile for modelling Distribution networks. This part of IEC 61968
defines a CDPSM profile (Common Distribution Power System Model). IEC 61968-13 will
mention the differences between this part of IEC 61968 and CPSM profile when they occur.
The data intended for initial configuration of distribution network applications includes the
applications such as distribution load flow calculation, dynamic network coloring, stability
studies due to the impact of Distributed Energy Resources on Distribution Networks,

– 10 – 61968-13  IEC:2008
Distribution remote control system data management, exchange of data between TSO
(Transmission System Operator) and DSO (Distribution System Operator), etc.
Consequently, the proposal is mainly based on IEC 61970-301, without, at the present time,
the Asset classes found in IEC 61968-11. In the future, assetType attribute of Asset class will
be used instead of PsrType if CIM IEC 61968-11 is normalized and incorporated officially in
the CIM. In this part of IEC 61968, class Location is defined in the IEC 61968-11 packages.
This part of IEC 61968 is valid for three-phase balanced and unbalanced distribution
networks. It is described as a single phase network and may have single- or two-phase
)
components such as single-phase laterals and transformers . However, some users may find
it convenient to restrict the proposed profile to include only the subset of three-phase
balanced networks and exclude support for single phase components. In the Clauses which
follow, the term “partial-phase devices” is used to describe components having less than three
phases.
5 Issues related to partial-phase devices modeling
5.1 General
The IEC 61970-301 standard already has support for partial phase conducting devices
through the phase-code attribute which may be a combination of any or all of the letters A, B,
C, and N. In general, one can think of a partial phase conducting device as being the same as
a full 3-phase device with some of the phases missing.
5.2 Impedances of unbalanced and partial phase devices
IEC 61970-301 specifies impedance of conducting devices in terms of the real and reactive
positive and zero sequence impedance. Unfortunately, this is only valid for perfectly
symmetric three-phase networks where all 3 phases have the same value of self-impedance
and the same mutual impedance value.
The impedance of unbalanced 3-phase conducting devices such as AC line segments shall be
specified as a three by three complex matrix where the diagonal terms specify the self
impedance of each phase and the off-diagonal terms specify the mutual impedance between
each phase pair. These values can be computed using Carson’s equations based on the
geometric mean radius, the linear resistance and the geometric arrangement of the three
phases on the pole. IEC 61970-301 provides all the parameters necessary in the Conductor
and WireArrangement classes. For 2-phase devices, the impedance matrix is two by two and
for single-phase devices, it is a complex scalar specifying the self impedance of the single
phase conductor.
5.3 Switches
IEC 61970-301 allows only two states for a switch device, i.e. open and closed. Thus for a 3-
phase switch, it suggests that all three phases of the switch always operate together and it
does not support the situation where, for example, phase A of the switch is open while phases
B and C are closed. Of course, a single-phase switch may be open or closed.
5.4 Partial phase continuity in radial networks
Many distribution networks are operated radially, meaning that there is only one path for
power to be supplied to any conducting device. For all phases of a device in a radial network
to be properly energized, all devices upstream shall have the same phases present. (For
———————
)
The USA radial electric distribution system is typically unbalanced. The main distribution feeder is three-phased
with single-phased tapped load. The model exchange format should support a three-phased, unbalanced model
to support, as an example, unbalanced load flow calculations.

61968-13  IEC:2008 – 11 –
example, it is not possible to energize all the phases of a three phase device via a partial
phase upstream device.)
However, this requirement is not enforced in this part of IEC 61968. Rather, it is up to the
importing DMS to check if this requirement is satisfied throughout the network.
6 CIM classes used and corresponding RDF
6.1 General
There is a large variety of voltage combinations in a substation. In addition, substations may
generally contain one, two or more voltage levels. The applications needing such “substation
type” information will deduce the substation type from the voltage levels it contains.
In general, substations may contain one, two or more voltage levels, the substation type will
be deduced by analyzing the voltage levels a substation contains. The class PSRType can be
used to distinguish these different substations. Class Location can be used to define the
absolute position of a Substation.
Annex E gives a complete example of a Distribution Network Data represented through CIM-
RDF. It should be pointed out that this complete example has been successfully tested during
CIM interoperability tests conducted by EPRI in 2004, 2005, and 2006.
From the standpoint of a data producer (exporter), the document describes a minimum subset
of CIM classes and class data which must be present in an XML formatted data file to comply
with CDPSM Minimum Data Requirements. From the standpoint of a data recipient (importer),
the document describes a subset of the CIM that an importer could reasonably expect to
receive in an XML data file designed to be compliant with the CDPSM Minimum Data
Requirements (see IEC 61970-501).
6.2 BaseVoltage and VoltageLevel
For every operating voltage found in the network, a BaseVoltage is created. An
ACLineSegment is associated to a BaseVoltage. A TransformerWinding is associated to a
BaseVoltage. PowerTransformer should be contained in a Substation.
Every Substation is associated with one or more VoltageLevel-s, each of which is in turn
associated with the corresponding BaseVoltage.
All the objects of the network, except ACLineSegment, PowerTransformer and Transformer
Winding should be contained within a VoltageLevel.

– 12 – 61968-13  IEC:2008

63


42


NOD10S61




NOD10S62



6.3 Containment hierarchy roots
The CPSM 2.0 profile of base CIM defines HostControlArea to be at the root of containment
hierarchy. In contrast, this specification defines HV/MV Substation as the root of the
containment hierarchy.
6.4 HV/MV substation
The containment hierarchy begins by HV/MV Substation.

AIGUE_HVMV



HV/MV Substation





910700
66270


6.5 MV/MV substation

AIGUE_MVMV



MV/MV Substation






910700
66270


61968-13  IEC:2008 – 13 –
6.6 MV/LV substation

AIGUE_MVLV



MV/LV Substation





910700
66270


If HV/LV Substation and LV/LV Substation have to be modeled, they will follow the same
principles as above.
In IEC 61968-13, all conducting equipment shall be a member of either a substation or of a
feeder. Normally, all substation equipment is housed in a physical enclosure such as a
building or a fenced area. A feeder is generally outside a physical enclosure and consists of a
collection, or connected set, of AC line segments, switches, transformers (which may or may
not be considered as a substation), etc. See further discussion of the feeder container object
under “Line” later in this document.
In addition, IEC 61968-13 shall support generalized equipment containers to group a set of
connected conducting devices – for example the CompositeSwitch device of IEC 61970-301.
6.7 Junction
In the CIM, devices are connected to each other by connecting a terminal of a device to a
common ConnectivityNode. A connectivity node may have any number of terminals connected
to it.
In a Distribution network, most ConnectivityNodes are contained in substations. However, in
some cases (e.g. a tapped distribution line), ConnectivityNodes may be located on lines which
are outside of substations. IEC 61970-301 defines the Junction class to indicate such
connectivity nodes. In this case, the ConnectivityNode and the Junction shall be located in a
virtual Substation.
However, a typical distribution network generally has many connectivity nodes outside of
substations along a feeder. Since these connectivity nodes serve no purpose other than to
connect two or more devices, it is generally not necessary to also specify them as a Junction.

– 14 – 61968-13  IEC:2008
)
6.8 Switch
Switches are contained either by VoltageLevel or by Bay. If Switches are contained by
VoltageLevel, Bay is not required. The abstract Switch is used only when we do not know the
detailed class.
IEC 61968-13 supports the following kinds of Switch devices:
Breaker (exists in CPSM): able to interrupt fault currents greater than normal load currents.
LoadBreakSwitch (exists in CPSM): able to interrupt normal load currents only.
Disconnector (exists in CPSM): no current interrupt capability.
Fuse (does not exist in CPSM): able to interrupt fault currents.
Jumper (does not exist in CPSM).
GroundDisconnector (does not exist in CPSM).


63


NOD10S61




AIGUE_HVMV



73109J0001
false






909255.1
56999


6.9 Bay
IEC 61970-301 supports the Bay object as a collection or container of a set of switch devices
and connectivity nodes inside a substation. Generally, a substation will contain several,
usually identical, bays containing connectivity nodes for incoming or outgoing lines (feeders)
Outgoing and incoming feeders are distinguished by the class PSRType. (PSRType and
Location are not mandatory).
———————
)
This should be forbidden, as switch is an abstract class.

61968-13  IEC:2008 – 15 –
This data is not mandatory. If Switches are contained by VoltageLevel, Bay is not required.

63


NOD10S61




AIGUE_HVMV



AIGUEC0601




OUTGOING FEEDER


AIGUEC0601
false






910696
66272


6.10 BusbarSection
Figure 2 describes the connectivity of a BusbarSection which has only one Terminal.
Terminal
BusbarSection
ConnectivityNode
IEC  941/08
Figure 2 – Connectivity of BusbarSection

– 16 – 61968-13  IEC:2008

63


NOD10S61




AIGUE_HVMV



AIGUEB0001













910720
66290


6.11 PowerTransformer
IEC 61968-13 supports transformer objects and their tap changers exactly as defined in
IEC 61970-301.
While an Autotransformer in reality does not have two distinct windings, it is acceptable in
IEC 61968-13 to model it as having two windings similar to conventional transformers in order
to define the voltage ratio
...