Applying Open Standards and Open Source Software for Smart Grid Applications: Simulation of

Distributed Intelligent Control of Power Systems

T. Strasser, M. Stifter, F. Andren, D. Burnier de Castro and W. Hribernik AIT Austrian Institute of Technology – Energy Department

Panel Session on: Open Source Software – Enabling the Smart Grid

2011 IEEE Power & Energy Society General Meeting Detroit, MI, USA – July 24th-28th, 2011

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Contents

• Motivation and Introduction

• Open Standards IEC 61850 & IEC 61499

• Free & Open Source Tools GNU Octave, PSAT & 4DIAC

• Simulation Concepts, Architecture and Topologies

• Case Study: An implemented CHIL Case Study

• Performed Tests and Results

• Conclusions and Outlook

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Motivation and Introduction

• According to the IEC Smart Grids roadmap intelligent devices are necessary for realizing smart grids

• Standard-based implementation is a key requirement for future developments

• Usage of distributed automation concepts for controlling electrical power systems

• Open source strategy and open standards as driver to push new developments for power & energy systems

• Well supported open source tools available

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Open Standards IEC 61850 & IEC 61499

• IEC 61850 – Power Utility Automation

– Interoperability standard for communication networks and systems for power utility automation

– Covers modeling, configuration and communication

– Standardization of the information model and how the information should be transferred between devices

– Definition of logical devices and logical nodes

– Object-oriented approach

– XML-based system configuration language

– Implementation of device functions not covered

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Open Standards IEC 61850 & IEC 61499

• IEC 61850 – Power Utility Automation

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Open Standards IEC 61850 & IEC 61499

• IEC 61499 – Reference Model for Distributed Control

– Standard for interoperability, configurability and portability in distributed automation applications

– Component-oriented basic building blocks called FBs

– Graphical intuitive way of modeling control algorithms through connecting in- and outputs of FBs

– Support for distribution and reconfiguration

– Definitions for the interaction between heterogeneous devices

– Based on existing standards of the domain (IEC 61131-3, IEC 61804, XML, etc.)

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Open Standards IEC 61850 & IEC 61499

• IEC 61499 – Reference Model for Distributed Control

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b) Device Model

d) Function Block

Types

·Manages Applications

·Commands· create· initialise· start· stop· delete· query

Communication Network

Device 3 Device 4 Device 5

Controlled Process

a) System Model

Device

ManagementResource B Resource C

Communication Interface

Process Interface

Resource A

Application 2

Device 1

Communication Interface

Process Interface

Scheduling function

c) Resource Model

Application 1

Application 3

Basic

STARTSTART

EX

1

INITINIT

INIT

1

INIT INITOINITINIT INITOINITO

EXOM AIN M AIN

Composite

Service

Interface

resourceapplication

STATUS

INITO(+)

STATUS

INITO(+)

startServicestartServicePARAMS

INIT(+)

PARAMS

INIT(+)

Device 2

Application 1

Application 3

Application 2

FOSS GNU Octave, PSAT & 4DIAC

• GNU Octave

– Environment for numerical computations

– High-level language (mostly compatible with Matlab)

– Provided under the GNU General Public License (GPL)

• Power System Analysis Toolbox (PSAT)

– Analysis of electric power systems

• Power, continuation power and optimal power flow calculations

• Signal stability analysis

– Provided under the GNU General Public License (GPL) for Matlab/Simulink and GNU Octave

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FOSS GNU Octave, PSAT & 4DIAC

• Framework for Distributed Industrial Automation and Control (4DIAC)

– IEC 61499 compliant implementation

– Provision of

• Engineering tool 4DIAC-IDE: Java/Eclipse implementation

• Runtime environment 4DIAC-RTE (FORTE): pure C++ implementation

– Available under the Eclipse Public License (EPL)

– Hosted at SourceForge: www.fordiac.org

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Concepts, Architecture and Topologies

• Very flexible simulation environment based on GNU Octave, PSAT and 4DIAC

• Different simulation topologies possible

– Power systems and controller simulation on the same PC-based hardware

– Power systems and controller simulation distributed on different PC-based hardware

– Power systems simulation on PC-based and controller execution on embedded hardware (CHIL)

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Concepts, Architecture and Topologies

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Concepts, Architecture and Topologies

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Concepts, Architecture and Topologies

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Implemented Case Study

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Implemented Case Study

• Automatic Tap Changer Controller (ATCC) Impl.

– As IEC 61499 basic function block

– Algorithm implemented in Structured Text (ST)

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Implemented Case Study

• Automatic Tap Changer Controller (ATCC) Impl.

– INIT algorithm

– REQ algorithm

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Implemented Case Study

• IEC 61850 compliant Implementation

– As IEC 61499 service interface function block

– Usage of the SystemCorp IEC 61850 stack

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Implemented Case Study

• IEC 61850 compliant Implementation

– Extract of the used IEC 61850 measurement Logical Node “MMXN” SCL configuration

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Implemented Case Study

• Resulting IEC 61499 Control Application

– Application model

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Implemented Case Study

• Resulting IEC 61499 Control Application

– System model

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Implemented Case Study

• Octave Communication Function

– Usage of socket communication (TCP)

– Implementation of the ASN.1 as defined by IEC 61499 encoding for the information exchange

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Implemented Case Study

• Adaptation of the Tap Changer Model in PSAT

– Tap changer model in PSAT have to be adjusted

– Have to be controlled from outside of the “PSAT world”

– Can be easily achieved since PSAT is open source

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Performed Tests and Results

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0.996

0.997

0.998

0.999

1

1.001

1.002

1.003

1.004

0 50 100 150 200 250 300

Vo

lta

ge

[p

.u.]

Time [15min]

Voltage profile with and without tap controller

0

0.05

0.1

0.15

0.2

0.25

0 50 100 150 200 250 300

Po

we

r [M

W]

Load profile on Bus 9

Conclusions and Outlook

• Approach for the co-simulation of power systems together with distributed control systems

• Usage of FOSS tools GNU Octave/PSAT & 4DIAC

• Standard-based implementation of control application(s) based on IEC 61499 & IEC 61850

• Different co-simulation possibilities (topologies)

• Future work will be focused on the embedded controller implementation of 4DIAC/IEC 61850

• Various CHIL lab tests are planned for the future

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Thanks for your attention!

Dr. Thomas Strasser

Electrical Energy Systems

Energy Department

AIT Austrian Institute of Technology

Österreichisches Forschungs- und Prüfzentrum Arsenal Ges.m.b.H.

Giefinggasse 2 | 1210 Vienna | Austria

T +43(0) 50550-6279 | M +43(0) 664 2351934 | F +43(0) 50550-6390

thomas.strasser@ait.ac.at | http://www.ait.ac.at

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