CIM 2 Modelica

CIM 2 Modelica FactoryAutomated Equation-Based Cyber-Physical Power System Modelica

Model Generation and Time-Domain Simulation from CIM

Francisco Gomez1, Prof. Luigi Vanfretti1,2, and Svein H. Olsen2

luigiv@kth.se , fragom@kth.seElectric Power Systems Dept.

KTHStockholm, Sweden

Luigi.Vanfretti@statnett.no svein.harald.olsen@statnett.no

Research and Development Division Statnett SF

Oslo, Norway

Overview

Acknowledgments

• This work has been funded in part by the EU funded FP7 iTesla project: http://www.itesla-project.eu/ and Statnett SF, the Norwegian power system operator.

• Work related to the iTesla Modelica power systems library presented here is a result of the collaboration between RTE (France), AIA (Spain) and KTH (Sweden) within the EU funded FP7 iTesla project: http://www.itesla-project.eu/

• Special thanks for ‘special training’ and support from

• Prof. Fritzson and his team at Linköping University

• Prof. Berhard Bachmann and Lennart Ochel, FH Bielefeld

• Background & Motivation– Modelica– CIM– CIM for Dynamics

• Modelica – Language Description– MetaModelica– CIM/UML to Modelica

• CIM 2 Modelica– Concept Design– Mapping– Simulation Engine

Research• Development of software architecture

supporting transformation from CIM, implementing tools for either translating from CIM to Modelica models

• Development of models of cyber-physical power systems components, communication network components, and other components from other domains

Application• iTESLA: Innovative Tools for Electrical

System Security within Large Areas• CIM provides standard format for power

systems data • Use of data from TSO

– Description of data equipment, power systems topology and measurements for model validation

Motivation

Modelica

• Modelica is a non-proprietary, object-oriented, equation based language to conveniently model complex physical systems

• Suitable modeling language for standardization and exchange of models

• Modelica tools, commercial and free of charge

• Electric power steering and controller model

[1] Andreas Deuring, Johannes Gerl, Harald Wilhelm“Multi-Domain Vehicle Dynamics Simulation in Dymola”,Modelica Conference, Dresden, 2011

• Thermodinamic Network of the ICE model

[2] L. Morawietz, S. Risse, H. Zellbeck, H. Reuss, T. Christ “Modeling an automotive power train and electrical power supply for HiL applications using Modelica”,Modelica Conference, Hamburg, 2005TU Dresden, University of Stuttgart, BMW Group, Germany.

Background

Common Information Model

• Conceived for information exchange: power systems topology, equipment, measurements

• Using UML representation to design a structured data model: Semantic transformation from real world to a model

• Standardization of the model diagrams for cyber-physical components

• Generators• Turbine Governors• Capacitors• Protections• Measurements

• IEC61970 provides standard data model for power systems components

Background

CIM for Dynamics• Dynamic models used in the industry

today use application specific data format and are embedded within the solver (integration routine)

• No information on how the model is implemented (i.e. actual equations used)

• Dynamic models can be represented in CIM, and exchanged among utilities

• Need to extend CIM to support more dynamics models

• Consider extend to support exchange of the model representation, not only of parameters

Background

doc SynchronousGeneratorMechanicalEquation

Extension for CIM Dynamics• Automatic model transformation

from CIM to a well defined (equation based) language

• Information exchange, parameters and equations with CIM and Modelica

• The benefit / role of CIM:• Modelling of the network are

done separate from the analytic• Existing Steady-State Solver

Engine (SSSE) can be used to initialize the transient study

Background

model gensal…

parameter Real wbase = 2 * pi * 50 "system base speed";parameter Complex Epqp = fpp + a * It;parameter Real delta0 = arg(Epqp);

parameter Real Pm0 = p0 + (id0 * id0 + iq0 * iq0) * Ra;Real delta "rotor angle";Real w "machine speed deviation, p.u.";…

initial equation   delta = delta0;  w = 0;

equation …   der(w) = ((Pm0 - D * w) / (w + 1) - Te) / (2 * H);  der(delta) = wbase * w;end gensal;

Overview

• Background & Motivation– Modelica– CIM– CIM for Dynamics

• Modelica – Language Description– MetaModelica– CIM/UML to Modelica

• CIM 2 Modelica– Concept Design– Mapping– Simulation Engine

Modeling Language

• Object-Oriented Language with class concept• Reuse of classes • Reuse of components• Scalable and Modular models

• Multi-Domain modeling

• Visual Acausal Hierarchical Component Modeling• Physical structure• No specification of data flow

direction

load

EM

DC

G

R L

Electrical

Mechanics

model DCMotorModelica.Electrical.Analog.Basic.Resistor r1(R =

10);Modelica.Electrical.Analog.Basic.Inductor i1;Modelica.Electrical.Analog.Basic.EMF emf1;Modelica.Mechanics.Rotational.Inertia load;Modelica.Electrical.Analog.Basic.Ground g;Modelica.Electrical.Analog.Sources.ConstantVoltage

v;equation

connect(DC.p,R.n);connect(R.p,L.n);connect(L.p,EM.n);connect(EM.p,DC.n);connect(DC.n,G.p);connect(EM.flange_b,load.flange_a);

end DCMotor;

Modelica

Modeling Language

• Modeling language based on equations, allow specification of mathematical models

• Typed Declarative Equation-based Textual Language

• Decoupling the model from the solver

model GENROUparameter Complex It=conj(S/VT) “Some comments

here“;   parameter Complex Is = It + VT/Zs;   parameter Complex fpp = Zs*Is;   parameter Real ang_P=arg(fpp);   parameter Real ang_I=arg(It);   parameter Real ang_PI=ang_P-ang_I;   parameter Real psi = 'abs'(fpp);equation

der(Epq) = (1/Tpd0)*(Efd0 -XadIfd);  der(Epd) = (1/Tpq0)*(-1)*(XaqIlq);

…anglev =atan2(p.vi, p.vr);Vt = sqrt(p.vr^2 + p.vi^2);

   anglei =atan2(p.ii, p.ir);    I = sqrt(p.ii^2 + p.ir^2);

…end GENROU;

Variable declaration

DAE Equations

Modelica

Power Systems Library in Modelica

• The FP7 iTESLA project develops a high level library for modeling power grid components

• Generators,• Governors,• Controls,• Branches,• Loads,• Buses,• Events

• The library makes available standardized power systems models usually available in power system tools only accessible through proprietary (and expensive) licenses

Modelica

CIM / UML to Modelica

• Modelica provides data definition and compilers for equation based modeling

• ModelicaML is a tool to create UML definition for Modelica models

• Design of classes, components and models using a data model representation:• Definition of start values for

components and definition of mathematical equations

• Code generation creates classes and models with relation between classes

Modelica

CIM / UML to Modelica

• Semantic transformation for automatic simulation directly from CIM definition

Modelica

• Background & Motivation– Modelica– CIM– CIM for Dynamics

• Modelica – Language Description– MetaModelica– CIM/UML to Modelica

• CIM 2 Modelica– Concept Design– Mapping– Simulation Engine

Overview

Process flow design

• Automatic generation of Modelica code from CIM/UML definition

• Manual design of CIM/UML definition and Mapping

• Loading CIM/XML and Mapping

• Semantic transformation into Modelica code:– Set initial values from load flow solution– Set connection between classes

CIM 2 Modelica

CIM 2 Modelica Mapping

•Relation between CIM classes and Power system library classes

•CIM Attributes and values -> Modelica Variables and starting values

•CIM relations between classes -> Modelica connection between components

or•CIM relations between classes -> Use of Modelica classes as objects

CIM 2 Modelica

Modelica Simulation Engine (architecture)

Simulation Engine

• Open-source software for cyber-physical system simulation

• Plug-in different compilers and solvers

• Enhancement to CIM:• Integration with PMU

measurements or simulation -> Harmonization with HDFS is an alternative

• Include the Modelica library code as part of the CIM standard

CIM 2 Modelica

Prop

ertie

s

Resu

ltsHDF5

JMOMC

PYTHON

JAVA

Dymola

Thank you! Questions?

luigiv@kth.se , fragom@kth.seElectric Power Systems Dept.

KTHStockholm, Sweden

Luigi.Vanfretti@statnett.no svein.harald.olsen@statnett.no

Research and Development Division Statnett SF

Oslo, Norway