=Paper=
{{Paper
|id=Vol-2010/paper5
|storemode=property
|title=Methodology For The Definition Of The Preliminary Architecture Of A Smart Energy System (SES)
|pdfUrl=https://ceur-ws.org/Vol-2010/paper5.pdf
|volume=Vol-2010
|authors=Gaetano D’Altrui,Lucio Tirone,Rosa Esposito,Marco Massenzi,Giuseppe Lentini
|dblpUrl=https://dblp.org/rec/conf/ciise/DAltruiTEML17
}}
==Methodology For The Definition Of The Preliminary Architecture Of A Smart Energy System (SES)==
https://ceur-ws.org/Vol-2010/paper5.pdf
Methodology for the definition of the preliminary
architecture of a Smart Energy System (SES)
Lucio Tirone, Gaetano D‟Altrui, Rosa Esposito Marco Massenzi, Giuseppe Lentini
Aster S.p.a. GALA S.p.a
via Tiburtina 1166, 00156 Rome (Italy) Via Savoia 43/47, 00198 Rome (Italy)
lucio.tirone@aster-te.it m.massenzi@gala.it
gaetano.daltrui@aster-te.it g.lentini@gala.it
rosa.esposito@aster-te.it
Copyright © held by the author
Abstract — This article describes a methodology for the organizes and visualizes all the information on the platform
definition of the preliminary architecture of the Smart Energy helping in decision support. SES integrates traditional utility
System (SES) platform. Unified Architectural Framework (UAF) tools, such as DMS and SCADA systems, aggregating and
has been used for a formal architecture description; it represents exposing the capabilities on the platform.
one of the first applications of UAF architectural framework to
the industrial energy sector. A business process analysis, through Main SES platform objectives are:
BPMN, allowed a clear vision of the processes among actors in
the energy market. Furthermore, the definition of the main Providing smart management for energy time shift, in
platform components, through SysML, allowed to define use order to store energy during low price time and
cases diagrams and to describe main platform components. As discharging during high price time;
result there were defined the preliminary SES hardware and
software architecture and the ways for the development of the Defining arbitrage services which provide energy
system. trading skills and algorithms to utilities in order to
Keywords— Energy management system, DER, UAF, BPMN,
obtain higher revenues than those obtainable by
SysML, UML. applying static rules;
Providing supervision and control services for real-time
I. INTRODUCTION monitoring of devices, systems and applications (Smart
The present article shows the application of System Home, Smart Building);
Engineering approach to the definition of the preliminary Applying strategies of demand side response
architecture of the IoT Smart Energy System (SES) platform. management;
SES wants to provide a flexible, reliable and scalable platform
in order to manage and optimize the use of DERs (Distributed Providing energy community services for the
Energy Resources) for multiple purposes. It should enable optimization and maximization of self-consumption in
connectivity, data collection, visualization, organization micro-grids;
(filtering, grouping, scheduling, dispatch, settlement) and Providing Aggregation services of virtual resources
optimization of DERs for a variety of grid, power, energy and (Virtual Power Plant, Virtual Energy Storage System,
services management and to help the energy utility in Enabled Virtual Units);
management and decision support. SES distributed architecture
and control algorithms create an „active‟ distribution Providing electric mobility management service in
management system to control the renewable and distributed order to manage the energy storage infrastructure and
energy resources in support of utility and community goals. energy stored through the electric vehicles.
Typical SES applications include integration of renewables
plants with the energy storage for carbon offset and in order to System engineering methodologies were used to define
reduce costs and microgrid operations for security, resiliency system stakeholders and their needs, to define principal
and market participation. services of the platform, to model business processes, to
describe main components of the platform, to derive the use
GALA group, one of the main Italian energy provider, has cases and a preliminary SES architecture. There were also
requested Aster to provide system engineering support for the considered two possible ways for the development of the
definition, technical-economical evaluation, and possible system, making a comparison between the costs.
implementation of the data acquisition software component,
smart management and decision support. In the present work, the application of the Unified
Architectural Framework (UAF) has been proposed; it
In particular, SES platform allows integration and represents one of the first applications of UAF architectural
connectivity among different DER, such as storage systems, framework to the industrial Energy sector and highlights the
smart electric vehicles and smart home devices and collects, capabilities of UAFP v 1.0 to [1]:
model architectures for a broad range of complex Component analysis: it provides the definition of the
systems which may include hardware, software, data, main components for the platform, starting from some
personnel and facility elements; existing components;
model consistent architectures for system-of-systems System preliminary design: it focuses on the platform
(SoS); use cases, the preliminary architecture and a cost
analysis.
support the analysis, specification, design, and
verification of complex systems; and The UAF has been applied for a formal definition of the
system architecture. An Architectural Framework establishes a
improve the ability to exchange architecture common practice for creating, interpreting, analyzing and using
information among related tools which are SysML Architecture Descriptions (AD) within a particular domain of
based and tools that are based on other standards. application or stakeholder community, ensuring that the overall
Enterprise Architecture is coherent [2].
II. OVERALL METHODOLOGY
The Unified Architectural Framework has been created to
The proposed approach, shown in Fig. 1, is a process support a standard representation also for non-defense
starting from the definition of the stakeholders and of their user organizations‟ ADs as part of their Systems Engineering (SE)
needs, proceeding with the definition of the platform services, technical processes. UAF supports a standard profile that can
modelling of business processes and use cases. be used to implement the UAF in UML/SysML tool [1].
Visual Paradigm is the software tool used for the SysML
model of the SES platform, taking into account Unified
Architectural Framework Profile (UAFP) v 1.0 prescriptions
[1]. The Unified Architectural Framework Profile (UAFP)
enables the extraction of specified and custom models from an
integrated architecture description (AD). The models describe a
system from a set of stakeholders‟ concerns such as security or
information through a set of predefined viewpoints and
associated views.
The UAFP supports the Department of Defense
Architectural Framework (DoDAF) 2.02, the Ministry of
Defence Architectural Framework (MODAF), Security Views
from Canada‟s Department of National Defense Architectural
Framework (DNDAF) and the North Atlantic Treaty
Organization (NATO) Architectural Framework (NAF) v 3.1.
UAFP is based upon the DoDAF 2.0.2 Domain Metamodel
(DM2) and the MODAF ontological data exchange mechanism
(MODEM).
The UAF metamodel improves the ability to exchange
architecture data between related tools which are UML/SysML
based and tools that are based on other standards.
UAFP 1.0 specifies one level of compliance to SysMLTM
profile using SysML v 1.3. UAFP imports the SysML profile
and defines constraints that pair together the application of
SysML and UAFP stereotypes.
The UAF views are classified for types (eg. Taxonomy,
structure, connectivity etc.) and domains (eg. Metadata,
Fig. 1. SES Methodology strategic, operational etc.); the UAF view matrix is represented
in Fig. 2. It specifies the different diagram types across the top
The final output of the work is the preliminary architecture and the domains along the side. UAF views used to represent
and costs of the SES platform. the SES architecture are [1], [3]:
The work has been divided in the following phases: Dc: Dictionary view aims to define all the elements
used in an architecture. In SES model this view has
Definition of glossary and acronym list: it aims to been applied to describe in tabular format the Project
define a common language for the project; acronym list and the glossary;
Operational analysis: it aims to define the stakeholders, Md-Tx: Metadata Taxonomy view shows the taxonomy
the services and the business processes of the platform; for metadata. In the present work, this view has been
used to define all the elements of the SysML model
(e.g. Block, interface etc.);
Op-Tx: Operational Taxonomy view shows the
taxonomy of types of Operational agents. It has been
used to collect use cases for each platform service;
Op-Pr: Operational Processes view describes the
activities which are normally conducted in the course of
achieving business goals that support a capability. In
SES model this view has been used to describe, using
BPMN diagrams, the typical processes in the energy
market;
Op-Tr: Operational Traceability view describes the
mapping between the capabilities required by an
Enterprise and the supporting operational activities and
operational agents. This view has been used to describe
Smart Energy System use cases; Fig. 2. UAF Matrix View
Pr-Tx: Personnel Views Taxonomy view shows the In the operational analysis, first of all system stakeholders
taxonomy of types of organizational resources. In SES and their user needs have been defined. In Fig. 3 all the SES
model this view has been used to define system stakeholders are depicted. During the analysis, a particular
stakeholders; attention has been given to the emergent actors in the energy
Rq: Requirement view is used to represent market. It has been examined the role of the Aggregator in
requirements, their properties and relationships between other European countries, in order to understand the future role
each other and to UAF architectural elements. In the of this actor in the Italian market. The aggregator is a demand
present work, this has been chosen to list in tabular service provider that combines multiple short-duration
format stakeholder needs; consumer loads for sale or auction in organized energy markets
[7].
Rs-Sr: Resource Structure view defines the physical
resources, e.g. capability configuration(s)/system(s) and
interactions necessary to implement a specific set of
Operational Performer(s). In SES model this view
describes the capabilities of the main platform
components, using SysML Internal Block Diagram;
Rs-Tx: Resource Taxonomy view shows the taxonomy
of types of resources. In SES model this view depicts
the principal capabilities of platform components, using
SysML Block Definition Diagram;
Sd-Tx: Standards Taxonomy view shows the taxonomy
of types of technical, operational, and business
standards, guidance and policy applicable to the
architecture. It has been used to list the reference
standards;
Sm-Ov: Summary & Overview view provides
executive-level summary information to allow quick
reference and comparison among architectural Fig. 3. Stakeholder Analysis
descriptions. ). In SES model this view has been applied
to describe system context; Furthermore SES services have been identified; the SES
Sv-Tx: Services Taxonomy view shows Service platform should provide the following services:
Specifications and required and provided services levels Energy efficiency service;
of these specifications needed to exhibit a Capability or
to support an Operational Activity. In SES model this Demand-side response service;
view describes system services, using SysML Block
Micro-grid management service;
Definition Diagram.
Energy pool management services;
Electric mobility management service.
As represented in Fig. 4, services are divided between interactions that take place within the Energy market. A very
services behind the meter and services beyond the meter. A important feature of the BPMN standard is that it often allows
service Behind The Meter (BTM) is referred to a renewable tight integration with software development systems. Indeed,
energy generating facility installed on the customer‟s property applications that allow the BPMN designer to represent the
and, on the customer‟s side, of the utility meter that produces process details using BPMN and then to translate that model
power intended for on-site use in a home, office building, or into software programs for the process management, are now
other commercial facilities. The use of a BTM service, available.
therefore, can reduce the customer utility bill. Services beyond
the meter, instead, allow integration with the grid providing In the present study the processes have been modelled by
ancillary services, load balancing, peak shaving, capacity Orchestration diagrams which represent the detailed
planning, etc. information and energy exchange between the actors of each
block.
Fig. 4. SES services
After defining system services, it has been possible to
analyze Business Model, in order to define the exchange of Fig. 5. SES Context diagram
data, documents and energy among the various actors involved
in the energy system. At this point, a component analysis for the definition of the
The definition of the Business Model requires a focus on functions of the main components of the SES architecture
the system context (its boundaries, external actors, external (CEMS, LEMS, DER) has been conducted; this activity is
interfaces). The system context diagram shows the system fundamental for the definition of system use cases. The
environment and the system boundary. It is not a predefined components have been represented using the SysML approach.
diagram of SysML or UML, but a variant of block diagram. In The Systems Modeling Language (OMG SysML™) is a
the center of the diagram there is the system under general-purpose modeling language that supports the
development. All currently known interaction partners are specification, design, analysis, and verification of systems [5].
denoted all around the system and associations are used to These systems may include hardware, software, data,
connect them. personnel, procedures, and facilities. SysML is an extension of
The context of SES system is represented in Fig. 5. The the Unified Modeling Language (UML), version 2, the
upper part of the figure indicates the main Actors that interact standard software modeling language. This approach also
with the system, while the section below illustrates external facilitates the integration of systems and software modeling.
systems exchanging information with the SES itself. An actor Each component has been described using both a block
is not a concrete system or a concrete individual, but has to be definition diagram (bdd) and an internal block diagram (ibd).
intended as a role. The block is the modular unit of structure in SysML that is
The language chosen to formally describe the business used to define a type of system, system component, or item that
process is the BPMN (Business Process Model and Notation), a flows through the system, as well as conceptual entities or
standard defined by the OMG (Object Management Group). It logical abstractions. The block describes a set of uniquely
provides a graphical representation to specify individual identifiable instances that share the block‟s definition. The
processes through a Business Process Diagram (BPD), with a block definition diagram is used to define block characteristics
standard, effective and intuitive notation for all the in terms of their structural and behavioral features, and the
stakeholders involved in the processes. The BPMN diagrams relationships between the blocks such as their hierarchical
are able to provide a common framework upon which it is relationship. The internal block diagram is otherwise used to
possible to describe interactions among different operators describe the internal structure of a block in terms of how its
working in the energy market [4]. The adoption of the BPMN parts are interconnected [5].
language allows to offer a clear vision of the processes among Furthermore, System Use Case diagrams have been used to
actors which have heterogeneous characteristics and different represent the goal of a system from the user‟s perspective [5].
responsibilities, also contributing to the modeling of the
Using the SysML language, formal Use Case diagrams are IV. COMPONENT ANALYSIS
drawn, showing the complete list of actors (primary and The functional characteristics of the main components of
secondary), as well as a full text description for each of them, the SES architecture have been analyzed on the basis of the
in order to illustrate the goal of the primary actor and the role technical documents provided by GALA and on all the
of the secondary actors. information collected during technical meetings. The principal
The result of these activities is the preliminary system components are:
architecture; two different ways of development for the
Local Energy Management System (LEMS): collects
platform were proposed, focusing on the pros and cons of the
and elaborates signals from DERs and implements
two solutions. Lastly, the preliminary costs of the two solution
possible actions. LEMS can work stand-alone or
have been analyzed.
interconnected with other LEMS and with the CEMS;
III. MODELLING OF PROCESSES IN THE ENERGY MARKET Distributed Energy Resources (DER): these are
electricity generation units located within the electricity
The processes, that the platform has to implement to distribution system at or near the end users [8]. DERs
guarantee each of the key services defined above, have been could be aggregated to supply energy demand;
validated through dedicated technical meetings with different
operators. Central Energy Management System (CEMS):
monitors, controls, manages and optimizes the energy
These processes have been modelled through the BPMN
system, in the attempt to reduce energy costs and
language by Orchestration diagrams which represent the
environmental impacts.
detailed information exchange between the actors of each
block. The BPMN diagrams offer a clear vision of the SES can be composed of one or more LEMS which can
processes among actors with different characteristics and work autonomously or can be interconnected with the CEMS.
responsibilities, also contributing to model the interactions that
take place within the Energy market. The components have been modelled by using the SysML
approach [5] and Visual Paradigm as a software tool. Each
Three main processes have been modelled: component has been depicted using both a block definition
diagram (bdd) and an internal block diagram (ibd).
Energy distribution process: it‟s the process which
characterizes the electricity transport through low The LEMS block definition diagram is shown in Fig. 6.
voltage distribution systems, analyzing its delivery to LEMS modules allow the visualization, monitoring and control
customers. The energy distribution is managed by the of all the energy resources managed, the elaboration of all data
DSO (Distribution System Operator) who is a natural or from DERs and external systems through algorithms which
legal person responsible for operating, ensuring the aim to optimize the energy management. Furthermore LEMS
maintenance of and, if necessary, developing the provides a smart management of electric mobility
distribution system in a given area and, where infrastructure and of battery charging / discharging processes
applicable, its interconnections with other systems and for vehicles.
for ensuring the long-term ability of the system to meet
reasonable demands for the distribution of electricity
[6];
Energy aggregation process: the energy aggregation is
managed by the aggregator, who exchanges
information with the prosumers he intends to aggregate
and classify according to consumer, geographic, or
common characteristics related to generation and
consumption of electricity. Through its systems, the
Aggregator, in addition to providing additional end-
user services, will collect and monitor aggregate
energy data that will also be available to external users.
Energy trading process: it describes the process of
energy trading in which the energy trader, who buys or
sells shares of energy at a given price, plays a primary
role. Fig. 6. LEMS Block Definition Diagram
The orchestration diagrams show clearly the user tasks, the LEMS can be interconnected to DERs in three different
interaction with other actors, the information exchanged and ways:
energy exchanges (physical flows). Furthermore the
Unmanaged Distributed Energy Resource;
orchestration diagrams describe the existing processes and
point out possible future modifications in the actors roles, Managed Distributed Energy Resource;
taking into account others European countries and directives.
Smart Energy Resource.
Fig. 7 shows the internal block diagram of the LEMS. conditions that must hold once the use case has completed, and
the Trigger, which identifies the event that causes the
activation of the use case.
Fig. 9 shows one example of Use Case Diagram,
representing the monitoring of aggregated energy data. One or
more use cases have been considered for all the platform
services. In the use case description, there have been
highlighted all the platform functionalities which need to be
used.
Fig. 7. LEMS Internal Block Diagram Fig. 9. Use case description: Monitoring of Aggregated Energy Data
Distributed Energy Resources (DERs) are energy sources After defining all system use cases, it has been derived a
that can be aggregated to provide the power needed to meet traceability matrix between use cases and system modules,
network demand. In the block definition diagram depicted in which allows to relate the actors and the LEMS and CEMS
Fig. 8, DERs have been grouped (using the Generalization modules involved in each use case. The matrix has been useful
connection type and a dedicated structure in Visual Paradigm in the architecture development phase.
to group the connections) by type of connection to LEMS
(Unmanaged, Managed, Smart), in the lower part of the VI. SOFTWARE AND HARDWARE ARCHITECTURE DEFINITION
diagram and by DER function in the upper part of the diagram.
From the previous activities of component analysis and use
case definition, it has been derived a preliminary architecture
of the SES platform. The Software architecture is characterized
by five different layers (Data Layer, Integration Layer,
Application Layer, Presentation Layer and Security Layer),
which define system software applications and the data security
infrastructure. Fig. 10 shows the preliminary software
application of SES system.
Fig. 8. DER Block Definition Diagram
V. SYSTEM USE CASES DEFINITION
The following step is the identification of the system Use
Cases, representing the goals of a system from the perspective
of the users, from the analysis of the business processes and of
the main platform components. Use Case diagrams show the
primary and secondary actors and a full text description for
each of them in order to illustrate the goal of the primary actor
and the role of the secondary actors. The Diagram provides a
high-level view of a system functionality, depending on how Fig. 10. SES Software Architecture
the actors use the system itself [5]. A typical use case
description may include the Preconditions, i.e. the conditions Two different solutions have been defined for the system
that must hold for the use case to begin, Post conditions, the hardware architecture. The first solution is a cloud based
architecture with only two physical servers used for the LEMS Energy storage management (Behind the Meter):
data collection. The other solution, otherwise, is based on platform for the efficient energy management in micro-
proprietary servers (Fig. 11). Preliminary costs have been grids. “Demand Response side” algorithms are used to
estimated for each solution. predict energy demand patterns and energy costs while
storage system are used to store or provide energy to
the prosumers, for energy time shift;
Energy storage management (Beyond the Meter):
platform allows the efficient management of virtual
energy pools, in order to support ancillary services in
transmission and distribution systems;
E-Mobility Energy Management: the platform allows
the smart management of e-mobility infrastructure. It
optimizes vehicles recharge times and brings the V2G
(Vehicle to Grid) connection in order to provide energy
to the grid for the demand side response.
For every step of development the goals, the services
Fig. 11. SES HW Architecture provided by the product, the stakeholders involved, the uses
cases implemented, and the software modules developed, have
been described.
VII. SYSTEM DEVELOPMENT APPROACH
Two possible approaches of system development have been CONCLUSIONS
proposed:
The present article shows the application of System
Waterfall approach: the SES platform is developed Engineering approach to the definition of the preliminary
simultaneously, using the classical waterfall method architecture of the IoT Smart Energy System (SES) platform to
which is a sequential design process, in which progress help energy utility in energy management and decision support.
is seen as flowing steadily downwards;
This paper represents one of the first applications of the
Agile approach: the SES platform is developed UAF (Unified Architectural Framework) for the definition of
iteratively; there are defined four different products architectures also in Industrial context. It highlights the UAF
composing the SES system and each of them capabilities in a formal description of system architecture.
implements some of the platform services. This allows
BPMN models allowed a clear definition of the main
an incremental development of SES modules.
processes of the platform, while SysML allowed to describe
The waterfall development has been organized in different main platform components and to depict use cases diagrams.
work packages:
As result of the work, it has been defined the preliminary
LEMS Specification and design; SES architecture and two possible ways for the development of
the system, making a comparison between the costs.
CEMS Specification and design;
LEMS development; REFERENCES
[1] OMG, Unified Architectural Framework Profile (UAFP) – Version 1.0 –
CEMS development; FTF Beta 1, 2016.
SES integration; [2] ISO/IEC/IEEE 1471:2007, “Recommended Practice for Architectural
Description of Software-Intensive Systems”
SES Verification and Validation. [3] Unified Architectural Framework Sample Problem (Non-Normative) –
Appendix C version 1.0, 2016.
This approach is characterized by one final release without [4] S. A. White, and D. Miers, “BPMN Modeling and Reference Guide”,
previous intermediate results with consequent big risks in the 2008.
implementation phase. [5] S. Friedenthal, A. Moore, r. Steiner, “A pratical guide to Sysml”, 2008.
The agile approach, otherwise, is characterized by an [6] Directive 2009/72/EC of the European Parliament and of the Council of
13 July 2009, concerning common rules for the internal market in
incremental development of products with fewer risks in the electricity and repealing Directive 2003/54/EC.
implementation phase. The process has been organized for the
[7] Directive 2012/27/EU of the European Parliament and of the Council of
development of the following products: 25 October 2012 on energy efficiency, amending Directives
2009/125/EC and 2010/30/EU and repealing Directives 2004/8/EC and
DER management: platform for DERs management. It 2006/32/EC.
aims to the integration, monitoring, command and [8] https://www.wbdg.org/resources/distributed-energy-resource
control of all DERs. The Analytics module suggests
the most efficient settings to guarantee security and
stability of the energy aggregated resources network;