IEC TS 61970-600-1:2017

IEC TS 61970-600-1 ®
Edition 1.0 2017-07
TECHNICAL
SPECIFICATION
colour
inside
Energy management system application program interface (EMS-API) –
Part 600-1: Common Grid Model Exchange Specification (CGMES) – Structure
and rules
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IEC TS 61970-600-1 ®
Edition 1.0 2017-07
TECHNICAL
SPECIFICATION
colour
inside
Energy management system application program interface (EMS-API) –

Part 600-1: Common Grid Model Exchange Specification (CGMES) – Structure

and rules
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.200 ISBN 978-2-8322-4637-5

– 2 – IEC TS 61970-600-1:2017 © IEC 2017
CONTENTS
FOREWORD . 6
INTRODUCTION . 8
1 Scope . 9
2 Normative references . 9
3 Terms, definitions and abbreviated terms . 9
3.1 Terms and definitions . 10
3.2 Abbreviated terms . 10
4 Exchange process . 11
5 Specifications and functionalities . 13
5.1 General constraints . 13
5.2 Model authority sets (MAS) . 14
5.3 File header . 15
5.4 File body . 16
5.5 Profiles and instance file types. 17
5.5.1 General . 17
5.5.2 CGMES profiles’ properties . 17
5.5.3 CGMES’ extensions . 19
5.5.4 Equipment profile and instance file . 22
5.5.5 Topology profile and instance file . 22
5.5.6 Steady state hypothesis profile and instance file . 22
5.5.7 State variables profile and instance file . 22
5.5.8 Boundary equipment profile and instance file . 23
5.5.9 Boundary topology profile and instance file . 23
5.5.10 Diagram layout profile and instance file . 23
5.5.11 Geographical location profile and instance file . 24
5.6 File exchange . 25
5.7 Boundary point – properties and location . 26
5.8 Model assembling process . 28
5.9 RDF/XML model validity . 30
5.10 Naming Convention . 30
6 CGMES governance . 34
6.1 General . 34
6.2 Versions of the CGMES and the profiles . 34
6.3 Conformity assessment . 35
6.4 Implementation process . 36
Annex A (normative) Template for further restrictions on naming . 37
Annex B (normative) Summary of specific rules for naming conventions . 38
B.1 IdentifiedObject.name . 38
B.2 IdentifiedObject.description . 38
B.3 IdentifiedObject.energyIdentCodeEic . 38
B.4 IdentifiedObject.shortName . 38
B.5 ConnectivityNode and TopologicalNode .fromEndIsoCode . 38
B.6 ConnectivityNode and TopologicalNode .toEndIsoCode . 39
B.7 ConnectivityNode and TopologicalNode .fromEndName . 39
B.8 ConnectivityNode and TopologicalNode .toEndName . 39
B.9 ConnectivityNode and TopologicalNode .fromEndNameTso . 39

B.10 ConnectivityNode and TopologicalNode .toEndNameTso . 40
B.11 Future developments on CIM for dynamics . 40
Annex C (normative) File header guidelines . 41
C.1 General . 41
C.2 Exchange scenarios . 41
C.3 Examples . 42
C.3.1 Example 1: File header of full model . 42
C.3.2 Example 2: File header of full model that is depending on another
model . 43
C.3.3 Example 3: File header of full model that is depending on a model and
supersedes another model . 44
C.3.4 Example 4: File header of difference model that is depending on a full
model and supersedes another full model . 45
C.3.5 Example 5: File header of difference model that is depending on a
difference model and supersedes another difference model . 46
Annex D (normative) PST transformer modelling . 48
D.1 General . 48
D.2 Mapping to CIM classes and attributes . 48
D.3 Reactance formulas summary table . 49
D.4 Symmetrical Phase shifters . 50
D.4.1 Single phase diagram and equations . 50
D.4.2 Expression of the angle and ratio per tap . 51
D.4.3 Expression of the equivalent series reactance given the angle . 51
D.4.4 Three-phase diagrams . 52
D.5 Quadrature booster . 53
D.5.1 Single phase diagram and equations . 53
D.5.2 Expression of the angle and ratio per tap . 53
D.5.3 Expression of the equivalent series reactance given the angle . 54
D.5.4 Three-phase diagrams . 54
D.6 Asymmetrical Phase Shifter . 55
D.6.1 Single phase diagram and equations . 55
D.6.2 Expression of the angle and ratio per tap . 55
D.6.3 Expression of the equivalent series reactance given the angle . 55
D.6.4 Three-phase diagram . 56
D.7 In-phase transformer and symmetrical phase shifter . 56
D.7.1 Single phase diagram and equations . 56
D.7.2 Expression of the angle and ratio per tap . 57
D.7.3 Expression of the equivalent series reactance given the angle and the
in-phase transformer ratio . 57
D.8 In-phase transformer and asymmetrical phase shifter . 58
D.8.1 Single phase diagram and equations . 58
D.8.2 Expression of the equivalent series reactance given the angle and the
in-phase transformer ratio . 58
D.8.3 Technology principles . 59
D.9 Detailed calculations and examples . 59
D.9.1 Symmetrical phase shifters with two cores . 59
D.9.2 Quadrature boosters . 63
D.9.3 Asymmetrical phase shifter . 67
Annex E (normative) Implementation guide . 74
E.1 General . 74

– 4 – IEC TS 61970-600-1:2017 © IEC 2017
E.2 TapChanger.neutralU vs PowerTransformerEnd.ratedU vs.
VoltageLevel.BaseVoltage . 74
E.2.1 Issue description . 74
E.2.2 Required implementation . 75
E.3 Angle of PhaseTapChangerTaple Point . 75
E.4 Slack generator. 75
E.5 qPercent SynchronousMachine . 76
E.6 TopologicalIsland . 76
E.7 Implementation of SSH and SV profiles . 76
E.8 Ground voltage levels . 76
E.9 LTCflag . 76
E.9.1 Issue description . 76
E.9.2 Use cases. 77
E.9.3 Required implementation . 78
E.10 ACLineSegment-s between different terminal voltages . 79
E.10.1 Issue description . 79
E.10.2 Required implementation . 79
E.11 Association from ConformLoadGroup/NonConformLoadGroup . 80
E.11.1 Issue description . 80
E.11.2 Required implementation . 80
E.12 Regulating control . 81
E.13 Implementation of the GeographicalRegion and SubGeographicalRegion . 81
E.14 Implementation of GeneratingUnit.normalPF . 81
E.15 Implementation of Power Transformer . 82
E.16 Interpretation of parameters of PowerTransformerEnd . 82
E.17 Implementation of Switch . 82
E.18 UnitMultiplier . 83
E.19 EnergySource: “voltageMagnitude” and “voltageAngle” . 83
Annex F (normative) CGMES profiles versions . 84
Bibliography . 85

Figure 1 – Dependencies between the profiles belonging to CGMES . 19
Figure 2 – Boundary point placed on a tie-line . 26
Figure 3 – Boundary point placed in a substation . 26
Figure 4 – HVDC as interconnection or internal line . 27
Figure 5 – HVDC grid . 27
Figure 6 – Assembly process . 29
Figure 7 – Main development stages of the CGMES . 34
Figure C.1 – Example work flow events. 41
Figure D.1 – Single phase diagram, phasor diagram and equations . 51
Figure D.2 – Example for symmetrical double core phase shifter . 52
Figure D.3 – Dual core and single core . 52
Figure D.4 – Single core, delta hexagonal . 53
Figure D.5 – Single phase diagram, phasor diagram and equations . 53
Figure D.6 – Dual core and single core . 54
Figure D.7 – Single phase diagram, phasor diagram and equations . 55
Figure D.8 – Dual core . 56

Figure D.9 – Single phase diagram, phasor diagram and equations . 57
Figure D.10 – Single phase diagram, phasor diagram and equations . 58
Figure D.11 – In-phase regulating auto-transformer . 59
Figure D.12 – Symmetrical phase shifters with two cores . 60
Figure D.13 – Detailed three phase diagram . 60
Figure D.14 – Detailed three phase diagram . 63
Figure D.15 – Single phase diagram . 64
Figure D.16 – Phasor diagram . 65
Figure D.17 – Detailed three phase diagram . 66
Figure D.18 – Phasor diagram . 67
Figure D.19 – Asymmetrical phase shifter with two cores . 67
Figure D.20 – Detailed three phase diagram . 68
Figure D.21 – Phasor diagram . 69
Figure D.22 – Asymmetrical phase shifter with a single core . 70
Figure D.23 – Phasor diagram . 71
Figure D.24 – Example of detailed three-phase diagram of voltage regulating auto-
transformer and quadrature booster . 72
Figure D.25 – Example of detailed winding diagram of voltage regulating auto-
transformer and quadrature booster . 73
Figure E.1 – Diagram ConformLoadGroup/NonConformLoadGroup . 80
Figure E.2 – Regulating control setup . 81
Figure E.3 – Power transformer modelling . 82

Table 1 – IdentifiedObject attributes . 33
Table 2 – IdentifiedObject attributes for ConnectivityNode in EQ_BD profile and for
TopologicalNode in TP_BD profile . 33
Table D.1 – Mapping of phase shift transformers to CIM classes . 48
Table D.2 – Mapping of symbols used in formulas to CIM attributes . 49
Table D.3 – Impedance variations in a phase shift transformer . 50
Table D.4 – Description of variables . 50
Table E.1 – Meaning of the combinations for TapChanger.TapChangerControl and
TapChanger.ltcaFlag . 79

– 6 – IEC TS 61970-600-1:2017 © IEC 2017
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ENERGY MANAGEMENT SYSTEM APPLICATION
PROGRAM INTERFACE (EMS-API) –
Part 600-1: Common Grid Model Exchange Specification
(CGMES) – Structure and rules
FOREWORD
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The main task of IEC technical committees is to prepare International Standards. In
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• the required support cannot be obtained for the publication of an International Standard,
despite repeated efforts, or
• the subject is still under technical development or where, for any other reason, there is the
future but no immediate possibility of an agreement on an International Standard.
Technical specifications are subject to review within three years of publication to decide
whether they can be transformed into International Standards.
IEC TS 61970-600-1, which is a technical specification, has been prepared by IEC technical
committee 57: Power systems management and associated information exchange.

The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
57/1815/DTS 57/1871/RVDTS
Full information on the voting for the approval of this technical specification can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 61970 series, published under the general title Energy
management system application program interface (EMS-API), can be found on the IEC
website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

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.
– 8 – IEC TS 61970-600-1:2017 © IEC 2017
INTRODUCTION
The purpose of the Common Grid Model Exchange Specification (CGMES) is to define the
interface between Transmission System Operators (TSO) software in order to exchange
power system modelling information as required by the European Network of Transmission
System Operators for Electricity (ENTSO-E) and TSO business processes.
The CGMES is used as a baseline exchange specification for the implementation of the
Common Grid Model (CGM) methodologies in accordance with the requirements for the
implementation of various European network codes and guidelines. The CGMES applies to
applications dealing with power system data management, as well as applications supporting
the following analyses:
• load flow and contingency analyses,
• short circuit calculations,
• market information and transparency,
• capacity calculation for capacity allocation and congestion management, and
• dynamic security assessment.
The conformity of the applications used for operational and system development exchanges
with the CGMES is crucial for the needed interoperability of these applications. ENTSO-E
therefore developed and approved the CGMES Conformity Assessment Framework as the
guiding principles for assessing applications’ CGMES conformity. This technical specification
relies on the CGMES Conformity Assessment Process operated by ENTSO-E in order to
ensure that the CGMES is properly implemented by suppliers of the applications used by
TSOs.
The CGMES is a superset of the former ENTSO-E CIM based data exchange standard (Profile
1) which was based on CIM14 (UML14v02) and has been used for certain network models
exchanges since 2009. The CGMES reflects TSO requirements (as known by 2014) for
accurate modelling of the ENTSO-E area for power flow, short circuit, and dynamics
applications whilst also allowing for the exchange of any diagram layouts including GIS data
of a grid model.
ENERGY MANAGEMENT SYSTEM APPLICATION
PROGRAM INTERFACE (EMS-API) –
Part 600-1: Common Grid Model Exchange Specification
(CGMES) – Structure and rules
1 Scope
This technical specification on the CGMES defines the main rules and requirements related to
the CGMES which are mandatory for achieving interoperability with the CGMES and for
satisfying business processes. In this document requirements are indicated as such in a
tabular format. Some descriptions are merely used for clarification and are marked
“Informational”.
The profiles which belong to CGMES are defined in IEC 61970-600-2:2017. The related
technical information and documentation (i.e. RDFS, OCL, XMI and HTML) needed for the
implementation of the CGMES, which is not copyrighted by either IEC or CENELEC, is
available at the ENTSO-E web site.
The CGMES is defined using information on the Common Information Model (CIM) available
in the public domain.
Future editions of this technical specification will be released to describe following CGMES
versions which will reflect additional requirements due to European network codes or
guidelines.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their
content constitutes requirements 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 61970-452, Energy management system application program interface (EMS-API) –
Part 452: CIM model exchange specification
IEC 61970-453, Energy management system application program interface (EMS-API) –
Part 453: Diagram layout profile
IEC 61970-456, Energy management system application program interface (EMS-API) –
Part 456: Solved power system state profiles
IEC 61970-552, Energy management system application program interface (EMS-API) –
Part 552: CIMXML Model exchange format
IEC 61968-4, Application integration at electric utilities – System interfaces for distribution
management – Part 4: Interfaces for records and asset management
3 Terms, definitions and abbreviated terms
For the purposes of this document, the following terms, definitions and abbreviated terms
apply.
– 10 – IEC TS 61970-600-1:2017 © IEC 2017
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
NOTE For definitions which are not specified in the CGMES the definitions in the IEC 61970 standards shall be
applied.
3.1 Terms and definitions
3.1.1
Common Grid Model Exchange Specification
CGMES
ENTSO-E specification used for the exchange of power system models between TSOs for the
purpose of performing bilateral, regional or pan-European studies in the frame of TYNDP or
TSOs’ projects
Note 1 to entry: This is based on IEC CIM Standards and further extended to meet Network Codes’ and projects’
requirements. The standard defines a set of data model exchange profiles.
3.1.2
profile
uniquely named subset of classes, associations and attributes needed to accomplish a
specific type of interface and based upon a canonical model
Note 1 to entry: This term may be used to define either the semantic model for an instance data payload or the
syntactic schema for an instance data payload. A profile may be expressed in XSD, RDF, and/or OWL files. An
instance data conforming to a profile can be tested in exchanges between applications. A profile is necessary in
order to “use” the canonical model.
3.1.3
CIM Extension
collection of classes, attributes and associations, which extend the standard IEC CIM model
in order to cover use cases not currently supported by IEC standards, and which are not
considered to be international use cases or are covered by a later version of the standard
which is not yet supported
3.1.4
ENTSO-E Extension
CIM Extension, specifically managed by ENTSO-E
3.1.5
boundary set
set containing all boundary points necessary for a given grid model exchange
Note 1 to entry: A Boundary set can have different coverage depending on the requirements of the common grid
model exchange. A complete boundary set is necessary to assemble a pan-European power system model.
3.1.6
boundary point
BP
connection point between two Model Authority Sets (MAS)
Note 1 to entry: A Boundary point could be a ConnectivityNode or a TopologicalNode placed on a tie-line or in a
substation. A Boundary point must be contained in a Boundary Set and must not be contained in the MAS of a
TSO. A Boundary point is referenced by Terminals in the MAS of a TSO. ConnectivityNode and TopologicalNode
are terms specified in IEC CIM standards. If a Boundary point is placed on a tie-line, the term X-Node is often used
instead of Boundary point. X-Node is therefore a specific type of Boundary point.
3.2 Abbreviated terms
IEC The International Electrotechnical Commission, headquartered in Geneva

DSO Distribution System Operator
TSO Transmission System Operator
ENTSO-E European Network of Transmission System Operators for Electricity
(ENTSO-E has 43 TSO members)
MRID CIM Master Resource Identifier
CIM Common Information Model (electricity)
CGMES Common Grid Model Exchange Standard
MAS Model Authority Set
IOP Interoperability Test
RDF Resource Description Framework
EQ_BD Boundary equipment profile or instance file
TP_BD Boundary topology profile or instance file
EQ Equipment profile or instance file
TP Topology profile or instance file
SSH Steady State Hypothesis profile or instance file
SV State Variables profile or instance file
DL Diagram Layout profile or instance file
GL Geographical Location profile or instance file
DY Dynamics profile or instance file
BP Boundary point
4 Exchange process
There are various levels at which the exchange of power system data/models is necessary. A
pan-European model exchange level covers the territory of all TSOs. Regional model
exchanges can be realised between different TSOs in one or more synchronous areas. A
model exchange on the national level includes interfaces between TSOs and DSOs, as well
as between different DSOs.
The purpose of model exchanges is not only to exchange the data from one authority to
another but also to satisfy the ultimate goal, namely to perform common studies using shared
data. All parties involved in the process should be able to perform the same types of studies
and be able to share project tasks between different parties which are using different power
system analysis applications. Indeed, the interoperability between different applications used
in the exchange process is therefore crucial in both reaching seamless data exchange and
obtaining comparable study results when using this data.
The CGMES covers these ENTSO-E and TSO business processes by defining the following
main types of exchanges valid for a particular study or process:
• Exchange of boundary set: An exchange of a boundary Set is necessary to prepare an
exchange of an internal TSO model and to assemble a common grid model. The latest
information on Boundary Sets covering the pan-European area is available to TSOs and
maintained in the ENTSO-E Network Modelling Database (NMD) where all TSOs negotiate
and agree on the boundary information.
• Exchange of an internal TSO model: A number of business processes require each TSO to
provide models of its internal territory. To describe its internal territory in a single stand-
alone exchange, a TSO is treated as a single model authority set and shall be able to
exchange all profiles defined in the CGMES. The TSO prepares its internal model in such
a way that it is easily and unambiguously combined with other TSO internal models to
make up complete models for analytical purposes. This type of exchange can also be

– 12 – IEC TS 61970-600-1:2017 © IEC 2017
applied for the interface between a TSO and a DSO, where models covering transmission
or distribution parts of the power system can be exchanged based on a mutual agreement
between the TSOs and the DSOs. In this case, and if a TSO requests a DSO model, the
DSO would provide its model in accordance with CGMES definitions which might be
extended by the TSO requesting this type of exchange.
• Exchange of a common grid model: A common grid model refers to the concept of having
one model which can be used for multiple purposes. The specification describes what is
needed to create an assembly of multiple TSOs' Individual Grid Models (IGM) of their
responsible territory into a regional or pan-European model. Different business processes
will require specific implementation of the profiles part of the CGMES and the exchange of
respective instance files to meet interoperability inside the business process. The
Common Grid Model meta-model description will ensure interoperability across the
business process.
ENTSO-E and TSO business processes (e.g. system development planning, protection
planning, operational planning, operation, fault study/simulation, market operation, etc.) are,
of course, more complex than these operations, but what is important to note is that all
processes are supported using only these basic kinds of interoperation.
Note that each power system model in CIM normally consists of multiple datasets (instance
files) as defined in IEC CIM standards and further specified by CGMES.
The CGMES supports node-breaker and bus-branch model exchanges. Moving forward the
procedures of the model exchanges using the CGMES, it is expected that equipment and
steady state hypothesis data (EQ and SSH instance files) will be the input source data for all
processes. This type of model should be the fully detailed model with all
disconnectors/breakers, etc. Any configuration changes are made by changing switch
statuses.
ID Specification Type
The CGMES defines equipment and steady state hypothesis profiles as an input, Requirement
EXCH1.
meaning that all results, whether topology or state variables profiles data, must
refer to the equipment and steady state hypothesis objects. Therefore, in the
case that both equipment and steady state hypothesis instance files are
available, there is no need to exchange topology or state variables instance files
in order to obtain a load flow.
For node-breaker model exchanges the TopologicalNodes represent the output Information
EXCH2.
from a topology processing on the detailed input source operational data. These
can be optionally exchanged to be used by tools which have an interest in the
computed buses.
For node-breaker model exchanges mRID (rdfIDs in serialisation) of the Information
EXCH3.
TopologicalNodes are not persistent.
For node-breaker model exchanges a topology instance file is not exchanged Requirement
EXCH4.
using a difference file.
For bus-branch model exchanges the TopologicalNodes must be persistent. Requirement
EXCH5.
If a contingency list is exchanged belonging to the model exchanged in bus- Requirement
EXCH6.
branch detail, it shall refer to ConductingEquipment (TopologicalNode, branches,
etc.). This results in a constraint on interoperability between planning and
operation processes.
If a contingency list is exchanged belonging to the model exchanged in node- Requirement
EXCH7.
breaker detail, it shall refer to ConductingEquipment (ConnectivityNode, which is
not artificial, Busbar, etc.).
If a model has mixed representation (node-breaker and bus-branch) then the Requirement
EXCH8.
profile URI in the header related to the Equipment Operation is not included as
only part of the network will include classes stereotyped with Operation.

5 Specifications and functionalities
5.1 General constraints
The following rules are general in nature or involve multiple classes. Additional rules are
defined in the notes to the individual classes in the profiles part of the CGMES.
ID Specification Type
All objects must have a persistent and globally unique identifier (it is Requirement
GENC1.
the mRID – see 5.2). In the ENTSO-E data exchange process this
unique identifier will be exchanged as rdf:ID.
Software solutions shall not use “name” related attributes (name, short Requirement
GENC2.
name, description, etc. inherited by many classes from the abstract
class IdentifiedObject) to link the power system model. Only mRID
(exchanged as rdf:ID) is used for this purpose.
The rdf:ID defined within a data exchange process is the only globally Requirement
GENC3.
unique and persistent identifier.
IEC 61970-552 defines the rdf:ID as UUID and its syntax (i.e. lower Requirement
GENC4.
case and number of characters for the different groups part of the
UUID). UUID algorithm ensures global uniqueness of the identifier.
Example UUID: f81d4fae-7dec-11d0-a765-00a0c91e6bf6
The CGMES defines the identifier as a case sensitive string which Requ
...