IEC 61968-5:2020

Application integration at electric utilities - System interfaces for distribution management - Part 5: Distributed energy optimization

IEC 61968-5:2020 is the description of a set of functions that are needed for enterprise integration of DERMS functions. These exchanges are most likely between a DERMS and a DMS. However, since this is an enterprise integration standard which may leverage IEC 61968-100:2013 for application integration (using web services or JMS) or other loosely-coupled implementations, there are no technical limitations for systems with which a DERMS might exchange information. Also, it should be noted that a DERMS might communicate with individual DER using a variety of standards and protocols such as IEC 61850, IEEE 2030.5, Distribution Network Protocol (DNP), Sunspec Modbus, or perhaps Open Field Message Bus (OpenFMB). One role of the DERMS is to manage this disparity and complexity of communications on the behalf of the system operator. However, the communication to individual DER is out of scope of this standard. Readers should look to those standards to understand communication to individual DER’s smart inverter.
The scope will be limited to the following use case categories:
• DER group creation – a mechanism to manage DER in aggregate
• DER group maintenance – a mechanism to add, remove, or modify the members and/or aggregated capabilities of a given group of DER
• DER group deletion – removing an entire group
• DER group status monitoring – a mechanism for quantifying or ascertaining the current capabilities and/or status of a group of DER
• DER group forecast – a mechanism for predicting the capabilities and/or status of a group of DER for a given time period in the future
• DER group dispatch – a mechanism for requesting that specified capabilities of a group of DER be dispatched to the grid
• DER group voltage ramp rate control – a mechanism for requesting that a DER group following a ramp rate curve
• DER group connect/disconnect – a mechanism to request that DER either isolate themselves, or reconnect to the grid as needed.

Intégration d'applications pour les services électriques - Interfaces système pour la gestion de distribution - Partie 5: Optimisation de l'énergie distribuée

IEC 61968-5:2020 est la description d'un ensemble de fonctions indispensables à l'intégration par les entreprises des fonctions DERMS. Ces échanges sont les plus susceptibles d'avoir lieu entre un DERMS et un DMS. Toutefois, étant donné qu'une norme d'intégration par les entreprises peut s'appuyer sur l'IEC 61968 100:2013 pour l'intégration d'applications (par le biais de services web ou de la technologie JMS) ou d'autres implémentations faiblement couplées, les systèmes avec lesquels un DERMS peut échanger des informations ne font l'objet d'aucune limite technique. De même, il convient de noter qu'un DERMS peut communiquer avec une DER individuelle en utilisant une variété de normes et de protocoles comme l'IEC 61850, l'IEEE 2030.5, le protocole DNP (Distribution Network Protocol – Protocole de réseau de distribution), Sunspec Modbus, voire Open Field Message Bus (OpenFMB). Un rôle du DERMS consiste à gérer cette disparité et cette complexité des communications au nom de l'opérateur système. Toutefois, la communication avec la DER individuelle est hors du domaine d'application de la présente norme. Il convient que le lecteur consulte ces normes pour comprendre la communication avec l'onduleur intelligent d'une DER individuelle.
Le domaine d'application est limité aux catégories de cas d'utilisation suivantes:
• création de groupe de DER – mécanisme de gestion de DER en agrégat;
• maintenance de groupe de DER – mécanisme d'ajout, de retrait ou de modification des membres et/ou capacités agrégées d'un groupe de DER donné;
• suppression de groupe de DER – suppression d'un groupe entier;
• surveillance du statut d'un groupe de DER – mécanisme de quantification ou de vérification des capacités réelles et/ou du statut d'un groupe de DER;
• prévision de groupe de DER – mécanisme de prévision des capacités et/ou du statut d'un groupe de DER pour une période donnée ultérieure;
• répartition de groupe de DER – mécanisme de demande de répartition des capacités spécifiées d'un groupe de DER sur le réseau;
• contrôle du taux de rampe de tension du groupe de DER – mécanisme permettant de demander qu'un groupe de DER respecte la courbe de taux de rampe;
• branchement/débranchement du groupe de DER – mécanisme permettant de demander que les DER s'isolent elles-mêmes ou se reconnectent au réseau, en fonction des besoins.

General Information

• Status: Published
• Publication Date: 17-Aug-2020
• 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: PPUB - Publication issued
• Start Date: 18-Aug-2020
• Completion Date: 28-Aug-2020

Overview

IEC 61968-5:2020 is an international standard developed by the International Electrotechnical Commission (IEC) focused on application integration at electric utilities. Specifically, it addresses system interfaces for distribution management related to distributed energy optimization. This standard defines a set of essential functions for enterprise integration of Distributed Energy Resource Management Systems (DERMS) with Distribution Management Systems (DMS) and other related enterprise applications.

The core purpose of IEC 61968-5 is to facilitate seamless communication and data exchange necessary for optimizing distributed energy resources (DER) on the electrical grid. It focuses on standardized mechanisms for managing groups of DER and their operational capabilities. While communication with individual DER devices-often involving protocols like IEC 61850, IEEE 2030.5, DNP3, and Sunspec Modbus-is outside the scope, this standard supports managing the complexity by integrating DERMS functions at the enterprise level.

Key Topics

IEC 61968-5:2020 covers a broad range of use cases critical to distributed energy optimization, including:

• DER Group Creation: Mechanisms for creating aggregate groups of DER to enable collective management and optimization.
• DER Group Maintenance: Processes for modifying group membership or adjusting the aggregated capabilities of DER groups.
• DER Group Deletion: Procedures for safely removing entire DER groups from system management.
• DER Group Status Monitoring: Methods to continuously quantify or ascertain real-time capabilities and status of DER groups for operators.
• DER Group Forecasting: Techniques for predicting the future operational capabilities and statuses of DER groups over specified time horizons.
• DER Group Dispatch: Request protocols to instruct DER groups to deliver specified power or ancillary services to the grid.
• Voltage Ramp Rate Control: Controls for managing DER group voltage outputs to follow defined ramp rate curves, optimizing grid stability.
• DER Group Connect/Disconnect: Commands for isolating or reconnecting DER groups to the grid as operational needs dictate.

The standard promotes enterprise integration architectures using technologies like web services or JMS messaging, building upon the foundational application integration framework outlined in IEC 61968-100:2013. It addresses enterprise-level interoperability challenges, ensuring flexibility to connect with a variety of legacy or modern control systems.

Practical Applications

Electric utilities and system operators leveraging IEC 61968-5:2020 can streamline the integration and management of distributed energy resources in power distribution networks. Practical benefits and applications include:

• Optimized DER Aggregation: Grouping DER assets for coordinated control enhances grid reliability and operational efficiency.
• Real-Time and Forecasted DER Analytics: Monitoring and forecasting tools enable proactive grid management and demand-response strategies.
• Standardized DER Dispatching: Utilities can issue dispatch instructions across diverse DER portfolios, supporting grid balancing and ancillary service markets.
• Voltage Regulation and Ramp Control: Improved voltage management helps maintain power quality and reduces operational risks.
• Flexible Connectivity: DERMS can interface with multiple DER communication protocols by handling complexities on behalf of the system operator.
• Scalable Enterprise Integration: Loose coupling via web services or messaging enables adaptable and vendor-neutral solutions.

Adopting IEC 61968-5 supports advanced distribution automation, demand response, and integration of renewable energy sources-key parts of smart grid initiatives worldwide.

Related Standards

IEC 61968-5:2020 works in conjunction with several important standards in the energy and smart grid domains:

• IEC 61968-100:2013: Provides the overall framework for application integration in electric utilities using web services and messaging, foundational to integrating DERMS functions.
• IEC 61850: Standard for communication networks and systems in substations; relevant for DER communication although out of IEC 61968-5’s direct scope.
• IEEE 2030.5 (Smart Energy Profile 2.0): Used for DER device communication, especially for smart inverters.
• DNP3 (Distributed Network Protocol): Widely used SCADA communication protocol for DER connectivity.
• SunSpec Modbus: Commonly adopted for solar and storage device monitoring and control.
• Open Field Message Bus (OpenFMB): Emerging framework to enable interoperability between distributed energy systems.

These associated standards cover detailed DER device-level communication, device models, and control protocols that complement the enterprise-level integration functions defined in IEC 61968-5.

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By implementing IEC 61968-5:2020, utilities can achieve enhanced interoperability, streamlined DER management, and effective integration of distributed energy resources-key drivers for modernizing power distribution and supporting the transition to cleaner, smarter energy systems.

Standards Content (Sample)

IEC 61968-5 ®
Edition 1.0 2020-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Application integration at electric utilities – System interfaces for distribution
management –
Part 5: Distributed energy optimization

Intégration d'applications pour les services électriques – Interfaces système
pour la gestion de distribution –
Partie 5: Optimisation de l'énergie distribuée

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IEC 61968-5 ®
Edition 1.0 2020-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Application integration at electric utilities – System interfaces for distribution

management –
Part 5: Distributed energy optimization

Intégration d'applications pour les services électriques – Interfaces système

pour la gestion de distribution –

Partie 5: Optimisation de l'énergie distribuée

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.200 ISBN 978-2-8322-8705-7

– 2 – IEC 61968-5:2020 © IEC 2020
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 9
2 Normative references . 10
3 Terms, definitions and abbreviated terms . 11
3.1 Terms and definitions . 11
3.2 Abbreviated terms . 11
4 Conventions . 12
4.1 UML diagrams. 12
4.2 Units of measure in DER enterprise integration profiles . 12
5 DER enterprise integration use cases . 12
5.1 General . 12
5.2 DER Group creation . 15
5.2.1 General . 15
5.2.2 Grouping requirements . 15
5.2.3 Challenges posed by dynamic distribution system configurations . 15
5.2.4 Challenges posed by enterprise information models . 17
5.2.5 Using arbitrarily-defined groups for DER aggregation . 19
5.3 Maintenance of DERGroups . 21
5.3.1 General . 21
5.3.2 DER Group maintenance example . 22
5.4 DER Group queries . 24
5.5 DER Group status monitoring . 25
5.6 DER Group forecast . 27
5.7 DER Group dispatch . 30
5.8 DER Group Connect/Disconnect . 32
5.9 DER group capability discovery. 32
5.10 DER group voltage regulation function . 33
Annex A (normative) Data requirements for DERMS profiles . 34
A.1 General . 34
A.2 DERGroups profile (constrained version) . 34
A.3 DERGroups profile (unconstrained version) . 35
A.4 DERGroupDispatches profile (constrained version) . 35
A.5 DERGroupDispatches profile (unconstrained version) . 36
A.6 DERGroupForecasts (constrained) . 36
A.7 DERGroupForecasts (unconstrained) . 37
A.8 DERGroupStatuses profile . 37
A.9 EndDeviceControls . 37
A.10 DERGroupQueries . 37
A.11 DERGroupStatusQueries . 38
A.12 DERGroupForecastqueries . 38
Annex B (normative) Super classes . 39
B.1 General . 39
B.2 CurveStyle class . 39
B.3 DERCurveData class . 39
B.4 DERFunction class . 39

B.5 DERMonitorableParameter class. 40
B.6 DERNamePlate class . 40
B.7 DispatchSchedule class . 42
B.8 EndDevice class . 42
B.9 EndDeviceGroup class . 43
B.10 EndDeviceGroup (constrained) for dispatches and forecasts . 43
B.11 EndDeviceGroup (unconstrained) for dispatches and forecasts . 43
B.12 Names . 44
B.13 NameType . 44
B.14 NameTypeAuthority . 44
B.15 Status class . 44
B.16 Version class . 45
Annex C (normative) Enumerated classes . 46
C.1 General . 46
C.2 abnormalOperatingPerformanceCategory enumeration class . 46
C.3 DERParameterKind enumeration class . 46
C.4 DERUnitSymbol . 47
C.5 FlowDirectionKind enumeration class . 48
C.6 normalOperatingPerformanceCategory enumeration class . 48
C.7 TimeIntervalKind enumeration class . 48
C.8 UnitMultiplier enumeration class . 49

Figure 1 – Architectural options for DERMS deployments . 13
Figure 2 – Reference architecture, IEC TR 62357‑1:2016 . 14
Figure 3 – Example of simple radial feeder . 16
Figure 4 – Example of feeder with alternate substation . 16
Figure 5 – Example of an interconnected distribution network . 17
Figure 6 – Common Information Model illustration . 18
Figure 7 – Request/Reply message exchange pattern for the creation of a DERGroup . 19
Figure 8 – Notification message exchange pattern for the creation of a DERGroup . 20
Figure 9 – Message exchange patterns to support adding or modifying DERGroup
membership or capabilities, or deleting a group member . 21
Figure 10 – Message exchange pattern reflecting deleting an entire DER group
(delete) . 22
Figure 11 – Message exchange pattern to support querying a DER group . 25
Figure 12 – Message exchange pattern for DER Group status monitoring (PULL) . 26
Figure 13 – Message exchange pattern for DER Group status monitoring (PUSH) . 26
Figure 14 – Example of points to represent battery storage group forecast . 27
Figure 15 – Battery DER Group availability example . 28
Figure 16 – Message exchange pattern for DER Group forecasting (PULL). 29
Figure 17 – Message exchange pattern for DER Group forecasting (PUSH) . 30
Figure 18 – Example Message exchange pattern for DER Group dispatch . 31

Table 1 – IEC 61968-5 Profiles . 9
Table 2 – IEC 61968-9 Profiles . 10
Table 3 – Document overview for IEC 61968-5 . 10

– 4 – IEC 61968-5:2020 © IEC 2020
Table 4 – DER Grouping functional requirements . 15
Table 5 – Example DER Group A membership before update. 22
Table 6 – Example DER Group A after adding a fourth member . 23
Table 7 – Example DER Group A membership after delete . 24
Table A.1 – IdentifiedObject . 34
Table A.2 – DERGroups profile . 35
Table A.3 – DERGroups (Unconstrained) Profile . 35
Table A.4 – DERGroupDispatches (Unconstrained) Profile . 36
Table A.5 – DERGroupDispatches (unconstrained) profile . 36
Table A.6 – DERGroupForecast (constrained) profile . 36
Table A.7 – DERGroupForecast (unconstrained) profile . 37
Table A.8 – DERGroupStatuses profile . 37
Table A.9 – DERGroupQueries . 38
Table A.10 – DERGroupStatusQueries . 38
Table A.11 – DERGroupForecastQueries . 38
Table B.1 – CurveStyle class . 39
Table B.2 – DERCurveData class . 39
Table B.3 – DERFunction class . 40
Table B.4 – DERMonitorableParameter class . 40
Table B.5 – DERNamePlate . 41
Table B.6 – DispatchSchedule . 42
Table B.7 – EndDevice . 43
Table B.8 – EndDeviceGroup class . 43
Table B.9 – EndDeviceGroup (constrained) dispatches class . 43
Table B.10 – EndDeviceGroup (unconstrained) for dispatches and forecasts . 43
Table B.11 – Names . 44
Table B.12 – NameType . 44
Table B.13 – NameTypeAuthority . 44
Table B.14 – Status class . 44
Table B.15 – Version class . 45
Table C.1 – abnormalOperatingPerformanceCategory . 46
Table C.2 – DERParameterKind . 46
Table C.3 – DERUnitSymbol . 47
Table C.4 – FlowDirectionKind . 48
Table C.5 – normalOperatingPerformanceCategory . 48
Table C.6 – TimeIntervalKind . 49
Table C.7 – UnitMultiplier. 49

INTERNATIONAL ELECTROTECHNICAL COMMISSION
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APPLICATION INTEGRATION AT ELECTRIC UTILITIES –
SYSTEM INTERFACES FOR DISTRIBUTION MANAGEMENT –

Part 5: Distributed energy optimization

FOREWORD
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International Standard IEC 61968-5 has been prepared by IEC technical committee 57: Power
systems management and associated information exchange.
The text of this International Standard is based on the following documents:
FDIS Report on voting
57/2223/FDIS 57/2252/RVD
Full information on the voting for the approval of this International Standard 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 61968 series, published under the general title Application
integration at electric utilities – System interfaces for distribution management, can be found
on the IEC website.
– 6 – IEC 61968-5:2020 © IEC 2020
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INTRODUCTION
Technology advancements in various types of distributed energy resources (DER), have driven
increases in their evaluation and employment by utilities, consumers, and third parties. These
DER are often connected to the grid at the distribution level where their presence in large scale
or volume could be disruptive if not designed, integrated, and managed properly.
Inverters, the power converter circuits that integrate DER to the grid, are highly-capable devices
with fast power controls and no inherent inertia such that they can respond quickly to commands
and local conditions. Even small-scale inverters tend to have processing and memory resources
and can support a variety of communication protocols and advanced functions. Over the last
few years, industry efforts have defined a wide range of standard grid-supportive functions that
inverters may provide and standard communication protocols that allow these functions to be
remotely monitored and managed.
If these inverter capabilities can be properly exposed and integrated into traditional utility
system operations, high penetration DER can be transformed from problematic uncertainties to
beneficial tools for distribution management. To achieve these potential benefits, it needs to be
possible not just to communicate to individual DER devices using standard protocols, but also
for the systems that manage DER, referred to herein as DER Management System or "DERMS",
to effectively inform other software applications regarding the resources available and to
exchange information that allows the DER to be managed effectively. Additionally, due to scale
of some devices, to optimize the management of DER they are managed in aggregate, referred
hereafter as "DER group management".
Traditionally, distribution systems have been operated without extensive controls or centralized
management. More advanced systems may have On-Load Tap Changing transformers (LTCs)
at substations, line regulators, and/or capacitor banks that operate to help optimize distribution
voltage and reactive power flow. In many cases, these devices may be fixed or configured to
operate autonomously. In a growing number of cases, however, a more central Distribution
Management System (DMS) has been used to coordinate their behaviour for a more optimized
overall effect. DMS functionality may reside at the utility operations centre, where single, large-
scale software manages many circuits, or it may reside in a more limited fashion at the
substation or other level, where smaller-scale systems act to manage individual feeders or
circuits.
Regardless of the scenario, the present generation of DMS systems is not designed to take
advantage of the capabilities that DER may offer. In most cases, DER support within a DMS is
limited to monitoring the output of "utility scale" DERs (> one megawatt). In addition, existing
industry standards define advanced functions for DER only at the individual device level, and
lack the more aggregated, feeder-level representations that are useful for enterprise integration.
This document develops appropriate enterprise-level functions for the integration of distributed
energy resources. These functions are intended to work in conjunction with the common
functions for smart inverters that have previously been defined.
The high-level use cases that are covered include management of DER group membership,
DER group status monitoring, DER group forecasting, and dispatching of real andreactive power
and other capabilities of managing DER as aggregated groups.
The IEC 61968 standard, taken as a whole, defines interfaces for the major elements of
interface architecture for Distribution Management Systems (DMS). Part 1: Interface
Architecture and General Recommendations, identifies and establishes requirements for
standard interfaces based on an Interface Reference Model (IRM). Parts 3-9 of this standard
define interfaces relevant to each of the major business functions described by the Interface
Reference Model.
– 8 – IEC 61968-5:2020 © IEC 2020
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.
This set of standards is limited to the definition of interfaces and is implementation independent.
They provide for interoperability among different computer systems, platforms, and languages.
Methods and technologies used to implement functionality conforming to these interfaces are
considered outside of the scope of these standards; only the interface itself is specified in these
standards.
APPLICATION INTEGRATION AT ELECTRIC UTILITIES –
SYSTEM INTERFACES FOR DISTRIBUTION MANAGEMENT –

Part 5: Distributed energy optimization

1 Scope
The scope of this part of IEC 61968 is the description of a set of functions that are needed for
enterprise integration of DERMS functions. These exchanges are most likely between a DERMS
and a DMS. However, since this is an enterprise integration standard which may leverage
IEC 61968-100:2013 for application integration (using web services or JMS) or other loosely-
coupled implementations, there are no technical limitations for systems with which a DERMS
might exchange information. Also, it should be noted that a DERMS might communicate with
individual DER using a variety of standards and protocols such as IEC 61850, IEEE 2030.5,
Distribution Network Protocol (DNP), Sunspec Modbus, or perhaps Open Field Message Bus
(OpenFMB). One role of the DERMS is to manage this disparity and complexity of
communications on the behalf of the system operator. However, the communication to individual
DER is out of scope of this standard. Readers are invited to look to those standards to
understand communication to individual DERs' smart inverter.
The scope will be limited to the following use case categories:
• DER group creation – a mechanism to manage DER in aggregate
• DER group maintenance – a mechanism to add, remove, or modify the members and/or
aggregated capabilities of a given group of DER
• DER group deletion – removing an entire group
• DER group status monitoring – a mechanism for quantifying or ascertaining the current
capabilities and/or status of a group of DER
• DER group forecast – a mechanism for predicting the capabilities and/or status of a group
of DER for a given time period in the future
• DER group dispatch – a mechanism for requesting that specified capabilities of a group of
DER be dispatched to the grid
• DER group voltage ramp rate control – a mechanism for requesting that a DER group
following a ramp rate curve
• DER group connect/disconnect – a mechanism to request that DER either isolate
themselves, or reconnect to the grid as needed
To support use cases in the preceding categories, this document specifies the following data
requirements (profiles) as shown in Table 1:
Table 1 – IEC 61968-5 Profiles
DERGroups DERGroupQueries
DERGroupStatuses DERGroupStatusQueries
DERGroupForecasts DERGroupForecastQueries
DERGroupDispatches DERGroupQueries

The profiles in the left column of Table 1 are the "base" DER profiles and appear in the Payload
section of IEC 61968-100 compliant messages. Those in the right column of Table 1 are the
"query" profiles that appear in the Request section of IEC 61968-100 compliant messages and
are used to specify the query parameters when using the "get" CIM verb.

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Additionally, this specification uses existing IEC 61968-9:2013, Application integration at
electric utilities - System interfaces for distribution management - Part 9: Interfaces for meter
reading and control profiles, as shown in Table 2, which are used for passing event information
and for the DER group connect/disconnect use cases. There are no extensions made to these
profiles, only the data specific to these use cases is passed.
Table 2 – IEC 61968-9 Profiles
EndDeviceControls
EndDeviceEvents
In a departure from prior IEC 61968 standards, this document supports specification of both a
"constrained" and an "unconstrained" version of each of the "base" profiles. The "constrained"
versions have a greater number of non-optional data elements and are intended for use with
the "create" and "created" CIM verbs. The "unconstrained" versions have all or almost all of the
CIM elements defined as optional, which is required to support operations involving the
"change", "changed", "delete", "deleted" and "get" CIM verbs.
This part of IEC 61968 contains the clauses listed in Table 3.
Table 3 – Document overview for IEC 61968-5
Clause Title Purpose
1 Scope The scope and purpose of the document are described.
2 References (Normative and Documents that contain provisions which, through reference
Informative) in this text, constitute provisions of this International
Standard.
3 Terms, definitions, and Establish the common terms used in this specification.
abbreviations
4 Document Conventions Message types related to the exchange of information for
documents related to maintenance and construction.
5 DER Enterprise Integration Use The specific requirements for and details of the message
Cases exchanges based on the use cases. Description of general
approach to the DER enterprise integration message type
terms and the static information.

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 60050-300, International Electrotechnical Vocabulary (IEV) - Part 300: Electrical and
electronic measurements and measuring instruments - Part 311: General terms relating to
measurements - Part 312: General terms relating to electrical measurements - Part 313: Types
of electrical measuring instruments - Part 314: Specific terms according to the type of
instrument
IEC TS 61968-2, Application integration at electric utilities - System interfaces for distribution
management - Part 2: Glossary
IEC 61968-9:2013, Application integration at electric utilities - System interfaces for distribution
management - Part 9: Interfaces for meter reading and control

IEC 61968-11, Application integration at electric utilities - System interfaces for distribution
management - Part 11: Common information model (CIM) extensions for distribution
IEC 61968-100:2013, Application integration at electric utilities - System interfaces for
distribution management - Part 100: Implementation profiles
IEC TR 62051, Electricity metering - Glossary of terms
IEC 62055-31, Electricity metering - Payment systems - Part 31: Particular requirements - Static
payment meters for active energy (classes 1 and 2)
IEC TR 62357-1:2016, Power systems management and associated information exchange -
Part 1: Reference architecture
IEEE 1547-2018, IEEE Standard for Interconnection and Interoperability of Distributed Energy
Resources with Associated Electric Power Systems Interfaces
3 Terms, definitions and abbreviated terms
For the purposes of this document, the terms and definitions given in IEC 60050-300,
IEC TS 61968-2, IEC TR 62051 and IEC 62055-31, and the following apply.
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
Where there is a difference between the definitions in this document and those contained in
other referenced IEC standards, then those defined in IEC TS 61968-2 shall take precedence
over the others listed, and those defined in this document shall take precedence over those
defined in IEC TS 61968-2.
3.1 Terms and definitions
3.1.1
Distributed Energy Resource Management System (DERMS)
The system which, on the behalf of other interested systems, manages the communications and
control of individual Distributed Energy Resource (DER (and may do this with a variety of field
message protocols), and aggregates this information and communicates with other utility
systems, such as a DMS.
3.2 Abbreviated terms
CIM Common Information Model
DER Distributed Energy Resource(s)
DERMS Distributed Energy Resources Management System
DMS Distribution Management System
EMS Energy Management System
IEC International Electrotechnical Commission
UML Unified modelling language
UUID Universally unique identifier
XSD XML Schema Definition
AMI Advanced Metering Infrastructure

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4 Conventions
4.1 UML diagrams
This document uses standard UML behavioural diagrams, specifically, sequence diagrams to
illustrate the integration between the DERMS and other enterprise or hosted systems that desire
to exchange information with the DERMS, or from enterprise systems to hosted or distributed
DERMS.
4.2 Units of measure in DER enterprise integration profiles
The IEC 61968-5 profiles contain elements specifying active, reactive, apparent power, and
voltage. The units of measure for these quantities are kW, kVAr, kVA, and V respectively.
DERMS characteristics
At a high level a DERMS has four characteristics:
• Aggregation – The DERMS facilitates the grouping of individual DER, into an aggregated
resource.
• Simplication – The DERMS handles the granular details of DER settings and presents simple
services to the system operator.
• Optimization – The DERMS should optimize the use of DER within various groups to get the
desired outcome at minimal cost and maximum power quality. Additionally, if managing
heterogenous types of DER within a group, the DERMS should know how to best leverage
the individual DER to get a specified outcome. This may involve equally spreading a request
across all the individual DER in a group, or having an algorithm that determines how to best
serve a request
• Translation – Individual DER may speak different languages, depending on their type and
scale. DERMS should handle these diverse languages, and present to the upstream calling
entity in a cohesive way.
However, the reader should remember that the scope of this specification is not for how the
DERMS behaves, or how it manages communication to individual DER, but is specifically the
communication between a DERMS and other enterprise systems or third-parties in a business-
to-business (B2B) mode of operation. Further, the reader should not impute any business logic
within these messages. This specification makes no recommendation as to the soundness of
any given implementation. For example, no recommendation is made as to the worthiness of
any given DER to be in group with other types of DER based-on location or capability. This sort
of business logic should be contained within a DERMS, and not proscribed in the associated
messages.
5 DER enterprise integration use cases
5.1 General
The DERMS works with groups of DER so that requests made of the DERMS for behaviour in
the power system can be handled in aggregate. This aggregation relieves the system operator
from having to manage each DER individually, a situation that becomes more problematic as
DER penetration in the power system continues to increase. To that end these use cases focus
on the creation and maintenance of groups of DER, capability discovery, DER
connect/disconnect, status monitoring and forecasting of these groups, and dispatching of
power and voltage.
Nominally, in a traditional utility, the DERMS may be an edge system similar to an AMI Head-
End. Like the AMI Head-End which gets status, events, and measurement data from meters
and may send control messages to the meters, a DERMS gets status from a smart inverter and
may send control messages (dispatch requests) to the smart inverter. While this is the nominal
configuration, this specification is not prescriptive as to architecture. The DERMS could be a
traditional edge system, it could be subsumed into a DMS, it could be hosted by an aggregator
in the cloud, or it could be a "DERMS in a box" in a substation per Figure 1.
This architecture assumes that there is a smart inverter that can be communicated with. There
are instances where DER is in the distribution network but is "dumb", with no ability to be
communicated with. Those types of DER are outside of the scope of this specification.

Figure 1 – Architectural options for DERMS deployments
It should also be emphasized that this specification for enterprise integration is the appropriate
domain per the reference architecture. See Figure 2.

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Figure 2 – Reference architecture, IEC TR 62357‑1:2016
Additionally, the scope of this standard is limited to the control functions of DER in aggregate,
and not the market-based motivations or event that might lead to such control.
As Figure 2 of IEC TR 62357-1:2016 illustrates, the enterprise communication between a
DERMS and other enterprise systems falls into the IEC 61968 domain while communication
between a DERMS and the actual DER (or specifically) the smart inverters attached to the DER,
within the IEC, is the realm of IEC 61850, although other standards and protocols are also used
such as IEEE 1815 (DNP), IEEE 2030.5, Sunspec Modbus, and OpenFMB. CIM-based
integration could also be accomplished as documented in IEC 62325-301 and IEC 62361-100.
As the work tha
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