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

• Background & Motivation– Modeling and Simulation– Modelica– CIM for Dynamics

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

• CIM 2 Modelica– Initial Conditions– Simulations

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

• 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 an OOP for declarative equation based mathematical language

• Non-proprietary language, suitable 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

class SynchronousMachineDynamics

Wires::SynchronousMachine

+ aVRToManualLag :Seconds [0..1]+ aVRToManualLead :Seconds [0..1]+ baseQ :ReactivePower [0..1]+ condenserP :ActivePower [0..1]+ coolantCondition :Float [0..1]+ coolantType :CoolantType [0..1]+ earthing :Boolean [0..1]+ earthingStarPointR :Resistance [0..1]+ earthingStarPointX :Reactance [0..1]+ ikk :CurrentFlow [0..1]+ manualToAVR :Seconds [0..1]+ maxQ :ReactivePower [0..1]+ maxU :Voltage [0..1]+ minQ :ReactivePower [0..1]+ minU :Voltage [0..1]+ mu :Float [0..1]+ operatingMode :SynchronousMachineOperatingMode [0..1]+ qPercent :PerCent [0..1]+ r :Resistance [0..1]+ r0 :Resistance [0..1]+ r2 :Resistance [0..1]+ referencePriority :Integer [0..1]+ satDirectSubtransX :PU [0..1]+ satDirectSyncX :PU [0..1]+ satDirectTransX :PU [0..1]+ shortCircuitRotorType :ShortCircuitRotorKind [0..1]+ type :SynchronousMachineKind [0..1]+ voltageRegulationRange :PerCent [0..1]+ x0 :Reactance [0..1]+ x2 :Reactance [0..1]

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 dynamics models

• CIM should also support the exchange 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 analyticExisting 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;

• Background & Motivation– Modeling and Simulation– Modelica– CIM for Dynamics

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

• CIM 2 Modelica– Initial Conditions– Simulations

Overview

Modeling Language

• Modeling language based on equations, allow specification of mathematical 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

• Typed Declarative Equation-based Textual Language

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

•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– Modeling and Simulation– Modelica– CIM for Dynamics

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

• CIM 2 Modelica– Initial Conditions– Simulations

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