IEC TR 62559-1:2019

IEC TR 62559-1 ®
Edition 1.0 2019-01
TECHNICAL
REPORT
RAPPORT
TECHNIQUE
colour
inside
Use case methodology –
Part 1: Concept and processes in standardization

Méthodologie des cas d'utilisation –
Partie 1: Concept et processus de normalisation

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IEC TR 62559-1 ®
Edition 1.0 2019-01
TECHNICAL
REPORT
RAPPORT
TECHNIQUE
colour
inside
Use case methodology –
Part 1: Concept and processes in standardization

Méthodologie des cas d'utilisation –

Partie 1: Concept et processus de normalisation

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.020 ISBN 978-2-8322-6427-0

– 2 – IEC TR 62559-1:2019 © IEC 2019
CONTENTS
CONTENTS . 2
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 8
2 Normative references . 8
3 Terms and definitions . 8
4 The use case development methodology . 11
5 Application of the use case methodology in standardization . 15
5.1 Motivation . 15
5.2 Reasons to use a use case repository (database) in standardization . 16
5.3 Classification of use cases . 17
5.4 Use case status . 19
6 IEC use case repository (UCR) management process . 19
6.1 Main requirements . 19
6.2 Overall process to create and maintain use cases . 21
6.3 Repository organization – the concept of workspaces . 22
6.4 Roles involved in the process and their areas of responsiblity . 22
6.5 Tools used in the process . 23
6.6 Detailed process description . 25
6.6.1 Activity: Import use case into UCR . 25
6.6.2 Activity: Check quality of use case . 25
6.6.3 Activity: Submit use case to validation team . 26
6.6.4 Activity: Process use case . 26
6.6.5 Activity: Update use case database and *-lists . 26
6.6.6 Activity: Discard use case import . 27
6.6.7 Activity: Notify use case developer . 27
7 Link to the IEC Smart Grid Standards Map . 27
7.1 General . 27
7.2 Motivation for the mapping tool . 27
7.3 Mapping tool chart content . 28
7.4 Linkage between mapping tool and UCMR . 29
8 Methods to identify the need for new standards on the basis of use case analysis . 30
8.1 General . 30
8.2 Terminology . 30
8.3 Reference architecture . 30
8.4 Use cases themselves . 30
Annex A (informative) Examples of using a bank machine (ATM) for cash withdrawal . 31
Bibliography . 40

Figure 1 – IEC 62559 standard series . 7
Figure 2 – IntelliGrid Methodology for Project Definition [Source: IEC PAS
62559:2008] . 13
Figure 3 – Using a bank machine (ATM) for cash withdrawal . 14
Figure 4 – Using a bank machine (ATM) for cash withdrawal – main activity steps . 15
Figure 5 – IEC Use Case Repository and main functions . 16

Figure 6 – Use case methodology elements and relationships . 18
Figure 7 – Overall process example (VT- Validation team) . 21
Figure 8 – Smart Grid mapping chart . 29

– 4 – IEC TR 62559-1:2019 © IEC 2019
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
USE CASE METHODOLOGY –
Part 1: Concept and processes in standardization

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
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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6) All users should ensure that they have the latest edition of this publication.
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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.
The main task of IEC technical committees is to prepare International Standards. However, a
technical committee may propose the publication of a Technical Report when it has collected
data of a different kind from that which is normally published as an International Standard, for
example "state of the art".
IEC TR 62559-1, which is a Technical Report, has been prepared by IEC systems committee
Smart Energy. This first edition, together with the other parts of the IEC TR 62559 series as
described in the Introduction, cancels and replaces IEC PAS 62559 published in 2008. This
edition constitutes a technical revision.
The text of this document is based on the following documents:
Enquiry draft Report on voting
SyCSmartEnergy/56/DTR SyCSmartEnergy/60/RVDTR

Full information on the voting for the approval of this Technical Report 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 62559 series, published under the general title Use case
methodology, 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.
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 – IEC TR 62559-1:2019 © IEC 2019
INTRODUCTION
Complex systems of systems such as Smart Grids, Smart Cities, Smart homes/buildings,
Active Assisted Living (AAL) systems, etc. call for cooperation between experts from several
different domains (home automation, health, energy, telematics, IT, etc.). In the specificiation
and design of such systems, standards play an essential role to obtain interoperable, safe,
secure and cost effective solutions. Thus, a common cooperation platform, including a
collaboration framework (terminology, quality guidelines, workflows, etc.), for involved
stakeholders is needed both in project development as well as in standardization work.
The work on the IEC 62559 series used IEC PAS 62559:2008 as a starting point.
IEC PAS 62559 defined a methodology for power system domain experts to determine and
describe their user requirements for automation systems, based on their utility business
needs. Since its publication in January 2008, the IEC PAS 62559 use case methodology has
been increasingly used within standardization and the need for a framework was recognized,
e.g. for IEC experts to provide use cases in a consistent manner. The IEC SMB SG3
recommendation 7, approved by the Standardization Management Board (SMB) at its
February 2010 meeting (SMB/4204/DL, Decision 137/10) requesting the urgent delivery of a
generic use case repository for all Smart Grid applications introduced a need to transform
IEC PAS 62559 to an IEC 62559 standard to support the development of an IEC use case
repository and to provide support for the use case methodolgy in general.
IEC PAS 62559:2008, as well as experiences from the many activities which have already
used it, provide central input to a full IEC 62559 standard series. This series will among other
be the basis for a common use case management repository in order to gather use cases
within IEC on a common collaborative platform and to organize a harmonization of use cases
in order to develop and provide broadly accepted generic use cases as basis for the further
standardization work. The new IEC 62559 series of standards is intended to support the
standardization bodies needs to create and manage a common use case repository (Parts 1
to 3). In contrast to the original scope of IEC PAS 62559:2008, the IEC 62559 series of
standards intends to be widely applicable for the development of different kinds of technical
systems also outside the Smart Grid domain. But, as the development of the series was
based on IEC PAS 62559, most examples come so far from the electrical energy supply
domain of Smart Grids.
Figure 1 provides an overview of the intended first parts of the IEC 62559 series mainly
describing the relation between Part 2 (the use case template), Part 3 (the XML import/export
format) and the common use case repository.
– Part 1: Concept and processes in standardization
IEC 62559-1 (this document) provides the basis for a common use case management
repository in order to gather use cases within IEC on a common collaborative platform and
to organize a harmonization of use cases in order to provide broadly accepted generic use
cases as basis for the further standardization work. It describes processes and provides
basics for the use case approach.
– Part 2: Definition of the templates for use cases, actor list and requirements list
IEC 62559-2 defines the structure of a use case template, an actor list and a list for
requirements. The document is mainly based on IEC PAS 62559:2008.
– Part 3: Definition of use case template artefacts into an XML serialized format
Based on IEC 62559-2 template, IEC 62559-3 defines the required core concepts and
their serialization into XML syntactic format of a use case template, an actor list and list
for detailed requirements. The XML format is used to transfer the content of the template
to other engineering systems (e.g. based on UML). It is intended to develop a UML profile
definition based on this part in future.
– Part 4: Best practices in use case development for IEC processes and company projects
IEC 62559-4 maintains the application of the use case methodology in
IEC PAS 62559:2008 relating to company projects. Part 4 gathers recommendations

around the application of the use case approach for project specific developments in a
broader sense, whereas Parts 1 to 3 concentrate on the application within standardization,
the use case template and the management of an IEC use case repository.

Figure 1 – IEC 62559 standard series

– 8 – IEC TR 62559-1:2019 © IEC 2019
USE CASE METHODOLOGY –
Part 1: Concept and processes in standardization

1 Scope
This part of IEC 62559, which is a Technical Report, is the basis for a common use case
repository, used to gather use cases within IEC on a common collaborative platform. The
repository is used to organize and harmonize use cases in order to provide broadly accepted
generic use cases as basis for the further standardization work.
This document gives an overview about the individual parts of the IEC 62559 series, provides
the background/basics for the use case approach defined therein (like terms or use case
types), and introduces processes for collaborative use case collection within IEC.
Operational documents like user manuals for software tools like the use case repository are
not described in detail as they will be available online and might as well be frequently
updated.
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.
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions 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
3.1
actor
entity that communicates and interacts
Note 1 to entry: These actors can include people, software applications, systems, databases, and even the power
system itself.
[SOURCE: IEC 62559-2:2015, 3.2]
3.2
role
role played by an actor in interaction with the system under discussion
Note 1 to entry: Alternative: A role represents the external intended behaviour of a party. A party cannot share a
role.
EXAMPLES A legally defined market participant (e.g. grid operator, customer), a generic role which represents a
bundle of possible roles (e.g. flexibility operator) or an artificially defined body needed for generic process and use
case descriptions.
Note 2 to entry: Legally or generically defined external actors may be named and identified by their roles.
[SOURCE: SG-CG/M490/E:2012-12, definition 3.17]
3.3
cluster
group of use cases with a similar background or belonging to one system or one conceptual
description
[SOURCE: SG-CG/M490/E:2012-12, definition 3.3]
3.4
domain
area of knowledge or activity characterized by a set of concepts and terminology understood
by the practitioners in that area
EXAMPLE Taken from Smart Grid/energy system area: generation, transmission, distribution, customer.
Note 1 to entry: Major area of similar technologies and organizational background, for the energy system some
domains are suggested in this document as examples throughout this document.
[SOURCE: ISO/IEC 19501:2005, Glossary]
3.5
use case
specification of a set of actions performed by a system, which yields an observable result that
is, typically, of value for one or more actors or other stakeholders of the system
[SOURCE: ISO/IEC 19505-2:2012, 16.3.6]
3.6
generic use case
use case which is broadly accepted for standardization, usually collecting and harmonizing
different individual use cases without being based on a project or technological specific
solution
[SOURCE: SG-CG/M490/E:2012-12; definition 3.7]
3.7
high level use case
use case which describes a general requirement, idea or concept independently from a
specific technical realization like an architectural solution
[SOURCE: SG-CG/M490/E:2012-12, definition 3.4]
3.8
business use case
use case that describes how business roles interact to execute a business process
Note 1 to entry: The business processes are derived from services, i.e. business transactions, which are needed
to achive different strategic goals for an organization; e.g. for the purpose of achieving specified and measurable
results/products for internal or external customers.

– 10 – IEC TR 62559-1:2019 © IEC 2019
3.9
system use case
use case that describes how system and/or business roles of a given system interact to
perform a function required to enable or facilitate the business processes described in
business use cases
3.10
use case template
form which allows the structured description of a use case in predefined fields
[SOURCE: SG-CG/M490/E:2012-12; definition 3.2]
3.11
use case repository
UCR
database, based on a given use cases template, for editing, maintenance and administration
of use cases, actors and requirements including their interrelations
Note 1 to entry: The UCR is designed as collaborative platform for standardization bodies, inter alia equipped
with export functionalities as UML model or text template.
[SOURCE: SG-CG/M490/E:2012-12; definition 3.13]
3.12
requirement
provision that conveys criteria to be fulfilled
[SOURCE: ISO/IEC Guide 2:2004, 7.5]
3.13
functional requirement
requirement that describes what the system must do
Note 1 to entry: They are actions in response to events, or actions performed autonomously. They represent
operations and features provided.
[SOURCE: IEC PAS 62559:2008, 7.2.6.2]
3.14
non-functional requirement
requirement that describes what qualities the system must contain from an execution and
performance perspective
Note 1 to entry: These are also known as “constraints”, “behaviour”, “criteria”, “performance targets”, etc. They
set limits or controls on how well the system performs the functional requirements.
Note 2 to entry: Non-functional requirements include: reliability, security, usability, upgradeability, expandability,
scalability, compatibility, safety, performance, and conformance.
[SOURCE: IEC PAS 62559:2008, 7.2.6.2]
3.15
repository
place where information like use cases can be stored, usually as a database
Note 1 to entry: Refer to use case repository.
[SOURCE: SG-CG/M490/E:2012-12; definition 3.12]

3.16
system
set of interrelated elements considered in a defined context as a whole and separated from
their environment
Note 1 to entry: A system is generally defined with the view of achieving a given objective, for example by
performing a definite function.
[SOURCE: IEC 60050-351:2013, 351-42-08]
3.17
unified modelling language
UML
graphical modelling language for the specification, construction, and documentation of parts
of software and other systems
Note 1 to entry: UML has a very broad scope that covers a large and diverse set of application domains.
[SOURCE: Based on UML Infrastructure Specification, v2.4.1]
3.18
Smart Grid architecture model
SGAM
suggested reference architecture for the Smart Grid area
[SOURCE: SG-CG/M490/C:2012-12]
4 The use case development methodology
The concept of use cases originates from software engineering where it is used to identify
functional requirements. A use case is simply a “story” about how a system will be used,
ideally developed by the people who will actually be using it. Use cases permit “users” too
clearly and comprehensively express their information needs in a manner that can be used by
information specialists and design engineers to develop the ICT/automation systems that will
exactly meet their requirements.
Thus its main focus is on the description of general functionalities of systems under design
and their environment. In general the description of use cases is independent of design
specifics and allows the identification of requirements. They provide links to artefacts from
different development viewpoints and due to that, they support a common understanding
between experts from different domains and technical/IT experts who have to implement
these functions.
The application of the use case methodology in power systems emerged from the need for a
methodology to interactively design the traditional power system infrastructure together with
its information and automation infrastructure to pursue the vision of a future highly reliable,
highly efficient, self-healing power system – the Smart Grid. Thus, the use case methodology
from software engineering was adapted to the use in energy systems in a research project –
the IntelliGrid project initiated by the Electric Power Research Institute (EPRI) – and the
project results were the basis for IEC PAS 62559:2008.
The process of developing use cases in general was described as shown in Figure 2 in
IEC PAS 62559:2008. It consists of the following types of people and project steps.
• Executives or other utility managers review business cases which describe and justify a
perceived business need. They then approve specific projects.
• Domain experts and project engineers are tasked to develop a project team to undertake
the project. As one of the first undertakings of the project team, all power system experts

– 12 – IEC TR 62559-1:2019 © IEC 2019
and other stakeholders (users) that could impact or be impacted by the project should be
identified.
• Domain experts review the existing IntelliGrid use cases for applicability and ideas .
• Domain experts develop a list of use cases (functional descriptions), covering not only the
specific business need but other user needs and future possibilities that could impact or
might be impacted by the project.
• Domain experts, with possible assistance by project engineers who understand the use
case process, draft the key use cases, capturing all of the necessary user requirements.
• Domain experts review and update these use cases to ensure their needs are captured
correctly and to assess possible misunderstandings, overlaps, holes, and other
inconsistencies.
• Project engineers assess and coordinate the use cases from which they develop a
comprehensive and detailed user requirements document. This detailed user requirements
document contains only user requirements.
• Information specialists apply the appropriate standards and technologies, based on the
user requirements document. The strategic vision of the IntelliGrid Architecture should be
used to determine the key standards and technologies.
• Design engineers develop the technical specifications, which combine the user
requirements from the domain experts, the strategic standards and technologies from the
information specialists, and the tactical approach to system development recommended by
the IntelliGrid Architecture.
___________
IntelliGrid use cases can be found at
http://intelligrid.info/IntelliGrid_Architecture/Use_Cases/IECSA_use_cases_overview.htm
Others are available. IEC repository is used for use cases supporting standards development.

[SOURCE: IEC PAS 62559:2008]
Figure 2 – IntelliGrid methodology for project definition
The user requirements as elicited by the use case process and ultimately described in the
detailed user requirements document cover:
• functions from the user perspective, including functional description of processes, user
choices, types of input data, types of results, and possibly display appearance;
• configuration issues, such as access to field data, electrically noisy substation
environment, control centre LAN, or cross-organizational interactions;
• performance requirements, such as availability, response times, latency, precision,
frequency of updated results, and other user parameters;
• security requirements, such as confidentiality, access restrictions, detection of failures
and/or intrusions, failure management, and other safety, security, and failure issues;
• data management requirements, such as sizes, numbers of devices, amounts of data,
expected growth over time, data access methods, data maintenance, and other data
management considerations;
• constraints, such as contractual, legal, regulatory, safety rules, or other issues that could
impact the requirements.
Additionally to the description of functions and requirements a use case identifies actors
which are interacting with the system under design to achieve particular goals. These actors
can for instance be other systems or human actors which are playing a role within a use case.
A role represents the external intended behaviour of a party in a use case while an actor is a
composition of one or more roles.

– 14 – IEC TR 62559-1:2019 © IEC 2019
Use cases can be specified on different levels of granularity and hierarchies of use cases are
often used to support a drill down description starting with high level (or primary) use cases
and leaving details to sub level (or secondary) use cases. The description of use cases is
supported using the visual Unified Modelling Language (UML) which provides use case
diagrams for this task, but often it is also realized using textual templates supported with
drawings. IEC 62559-2 provides a word template for use case description allowing for both
the use of descriptions based on plain text and/or graphical visualization which might also use
UML syntax.
Figure 3 shows a business use case (BUC) example: Using a bank machine (ATM) for cash
withdrawal.
Figure 3 – Using a bank machine (ATM) for cash withdrawal
The main objective of the use case is to provide the customer (the primary actor) with cash
and the use case is a business use case (BUC) – see 3.8. To implement a technical
realization of the business use case, three actors are involved (customer, ATM owner and
bank) and their roles, motivation, preconditions, postconditions and interactions are illustrated
in Figure 4:
Figure 4 – Using a bank machine (ATM) for cash withdrawal – main activity steps
An example of the corresponding use case description using the IEC 62559-2:2015 template
is found in Annex A.
5 Application of the use case methodology in standardization
5.1 Motivation
The use case concept can be used to identify system requirements and actors that make up a
reference architecture of complex systems of systems that serves as a basis for
standardization. The use case methodology is already widely used within IEC as well as other
standardization bodies, which motivates the re-use of results and making sure that existing
work is taken into account. The concept is that the use cases themselves might not have the
status of International Standards, but that consolidated so-called generic use cases (GUC)
are pre-standard input to various standardization processes.
As already mentioned the development of complex systems of systems requires people from
different domains (and therefore different technical committees (TCs) or even different
standards development organizations (SDOs) or other organizations) to be involved. Here use
cases can serve as a common denominator for communication, standards development and
as a basis for interoperability tests. In addition to that, a collection of use cases around
several systems can allow SDOs to identify gaps in their standardization portfolio. Identified
gaps might serve as the basis for suggesting new work item proposals (NPs).
Considering the approach of the IEC 62559 series, the use case methodology leads to a
collaborative platform between different TCs or SDOs and defines the status of use cases,
which are collected and published in the IEC use case repository shown in Figure 1.
• Developed as a tool for system engineering projects some advantages are also related to
using this method for standardization purposes: Use cases gather requirements,

– 16 – IEC TR 62559-1:2019 © IEC 2019
information about functionalities, processes and respective actors in a standardized,
structured form.
• They enable a common understanding between different stakeholder groups and its
coordination. A discussion of these use cases with its requirements and descriptions
should enable a common understanding between different sectors, committees or even
organizations. Therefore, use cases descriptions are mainly used for new, complex
systems of cross-cutting nature. In this respect they can be seen as link between new
requirements (also from external sources representing market needs) and standardization.
As use cases can be seen as a bracket for a number of standards and standards
activities, they support the management of standardization activities and provide guidance
for users of standards.
• They help to manage the complexity of standards development in complex systems.
Depending on the level of granularity of the description, the use cases support the
assignment and management of standards and committees which are related to the
respective use case as well as the development of a standardization work programme.
• Use case descriptions support the standards development in the design and definition
phase, e.g. in areas like interoperability, terminology, safety, and security.
• Beneath these basic functions, validated use cases can be used for testing or training
purposes. Therefore, use cases will not only have preparatory and administrative functions
for SDOs and the development of standards; they are needed to prove interoperability and
to support the use of interoperability standards.
• Use cases described in the given template are basis for further engineering in the TCs or
even for individual projects.
• Beneath the support for the development process of standards use cases provide
guidance for standards users as use cases can be combined with reference architectures
and standards and therefore help users to find the right standards.
5.2 Reasons to use a use case repository (database) in standardization
Although it is possible to describe use cases in a word processing format, establishing a use
case repository will provide many advantages for SDOs when the methodology is introduced
in a broader scale. The IEC use case repository (UCR) is a database, based on the
IEC 62559-2 use case template, for editing, maintenance and administration of use cases,
actors and requirements including their interrelations and supporting lists such as:
• standardized list of information objects exchanged between actors;
• list of references (e.g. standards) being used in use cases.
A schematic overview of the use case repository and the main functionalities is given in
Figure 5.
Figure 5 – IEC use case repository and main functions

The main advantages for using a common IEC repository in standardization are as follows.
• Collaborative platform
As said before, the use cases enable an exchange of basic ideas across the different
sectors and stakeholders of the industry, different TCs or even different organizations.
Such an exchange needs a collaborative platform, which increases the transparent design
and the common development of new systems.
• Administration
Considering the different iterative working steps from draft via discussion to a validated
use case there is a need for tool support: for example, the tracking of changes or
contributing authors, discussions, etc.
• The latest use cases and related data are always available in the database.
• Search functions and transparency
It will be easier to find an appropriate use case. Duplication of use cases can be
minimized using a repository for the whole community. Therefore, transparency is
increased when use cases, related discussions, and the development process are visible
for the community.
• Harmonization of use cases
The repository provides pre-defined content for some fields like actors or domain/zones.
This will be a useful help for the use case author, but also aligns different use cases
among each other as they use the same terms.
• Voting/validation of use cases
Validated use cases are the fundamental basis which enables the evolution of new
standards in the different TCs. The repository supports the process of validation.
• Different template versions
The complete IEC template is complex and designed for a detailed analysis. Especially at
the start, a use case repository provides easier short templates. Without rewriting these
short templates, they can be extended in a repository. Further fields and cells can be filled
according to the needs of the users and according to the phase of the design process.
• Analysis of use cases
Some fields of the use case template and some features of the use case repository
support the analysis of use cases: search and filter functions (e.g. according to a specific
actor, specific reports out of the database), gathering information from various use cases
(e.g. the information exchanged between different actors in order to define the message
load or common requirements). Additionally, use cases can be sorted according to the
classification fields: prioritization, maturity, etc.
• Link to other use cases
In a repository it is easier to link the use case to other use cases and to
administrate/report these links (use case networks, clusters, interrelations).
• Further engineering and export functions
The repository provides export functionalities, including a link to UML for further detailed
engineering, reusing the developed use case (IEC 62559-3).
5.3 Classification of use cases
Because use case descriptions are supporting various tasks, the granularity and the content
of the use case description varies broadly. A use case in general describes functions of a
system or a business process and related information exchange, mainly in a technology-
neutral way (depending on the level of detail). It identifies participating actors that can for
instance be other systems or human actors that are playing a role within a use case. Figure 6
shows the relationships between the different use case methodology elements:

– 18 – IEC TR 62559-1:2019 © IEC 2019

Figure 6 – Use case methodology elements and relationships
• Business case
A business case is an explanation or set of reasons describing how a business decision
will improve a business, product, etc., and how it will affect costs, profits and attract
investments, equivalent to strategic goals and principles which drive business processes.
Example: Reduce energy system losses
• Conceptual description / user stories
A co
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