maurer by pengxuebo

VIEWS: 19 PAGES: 17

									        SystemDesign

          Modelica/Dymola
    a multidomain modelling and
simulation environment for fuel cells?




             SystemDesign
Challenge

easy to use models for several purposes (concept
 studies, design, optimisation, control design, HIL-
 Simulation, customer consulting, life cycle cost
 analysis, ..)
various time scales and granularity of modules
scales of dynamic behaviour (balance between details
 and speed)
hybrid process (continuous and discreet)
reuse and exchange of existing models
model sharing



                    SystemDesign
Benefits



better understanding of behaviour and processes
 (complete analysis capabilities)
faster design and evaluation of new concepts
evaluation of critical states and limits
multi-domain system integration
multi-level simulation (same component – different
 views)
model exchange and modelling network



                    SystemDesign
Multidomain Modelling

                                Multidomain-Model


          Specialised Tools                             Modelling by
             + Interfaces                           Uniform Language



 Equations                  Blocks             System Dynamics         Multiports


 Excel                      Simulink           STELLA                  Modelica
 Matlab                                        BerkeleyMadonna         VHDL-AMS
 ACSL                                          Powersim
                                               Vensim


                                SystemDesign
System Dynamics vs. Signal Flow Modelling



                             Example
                            mass of the incoming
                             freight car: 60 t
                            mass of the resting freight
                             car: 30 t
                            velocity: 3 m/s
                            four buffers with spring
                             and friction (105 mm,
                             30 kN, 600 kN, 200 kN)
                            brakes not applied


                 SystemDesign
System Dynamics




                  SystemDesign
Signal Flow (Simulink)




                  SystemDesign
Physics of Dynamical Systems


area              quantity           potential
gravitation       mass               gravitational
hydraulics        volume             pressure
mechanics
  translational   momentum           velocity
  rotational      angular moment.    angular velocity
thermodynamics    entropy            temperature
electricity       charge             electrical
chemistry         am. of substance   chemical


                    SystemDesign
dynamic systems


                                 information
                                 energy
              exchange of
  system                         momentum,

  states                         angular momentum

  processes                      electric charge
                                 entropy
                                 mass,
                                 amount of substance


                  SystemDesign
Multiport Modelling

System         thermal connection (temperature, heat)
equations      mechanical connection (v, p; w, L; p, V)
states         electrical connection (U, Q)




                                                          1/s




                    SystemDesign
Hierarchical Aggregation
                   Structured process model
                                                hierarchical
                                                aggregation

                                                                Idee und Schaubild von
                                                               R. Hanke, M. Mangold und
Level of process
units                                                               K. Sundmacher
                                                                 Max-Planck-Institut für
                                                                  Dynamik komplexer
Level of phases
                                                                       Systeme
                                                                      Magdeburg


Level of storages
                                     Storage level library

                    Virtual fuel cell lab


                                            SystemDesign
VHDL-AMS vs. Modelica: resistor
                                                model Resistor „einfacher Widerstand“
entity Resistor is
                                                   pin p, n;
   port (terminal p, n: electrical)
                                                   parameter SI.Resistance R = 5;
  generic (R: REAL:= 5);
                                                protected
end Resistor;
                                                  SI.Voltage v;
                                                equation
architecture R1 of Resistor is
                                                 v = p.v – n.v;
 quantity vR across iR through p to n;
                                                 p.i + n.i = 0;
begin
                                                 v = R*p.i;
 vR == R*iR;
                                                end Resistor;
end R1;

                                                connector pin
nature electrical is
                                                 SI.Voltage v;
   voltage across
                                                 flow SI.Current i;
   current through;
                                                end pin;




                                      SystemDesign
object orientated modelling language
  – hierarchically structured
  – support effective library development and model
     exchange
  – non causal modelling (differential, algebraic and
     discrete equation)
for multi domain modelling (hydraulics, mechanics,
 electronic, thermodynamics, control engineering, …)
open source (www.modelica.org)


                    SystemDesign
Dymola




         SystemDesign
Related Tools



Dymola-Simulink Interface
  – A Modelica model can be converted into a S-function
    block
IDA indoor climate and energy from Equa
  – Equa is working towards making IDA Simulation
    Environment fully Modelica compatible




                     SystemDesign
Examples


HIL-Simulation of the Hydraulcs and Mechanics of on
 Automatic Gearbox (BMW)
Modelica Application for Camless Engine Valvetrain
 Development (Ford)
Modeling und Simulation of Refrigeration Systems
 with the Natural Refrigerant CO2 (Airbus)
Simulation of Thermal Building Behaviour in Modelica
 (Uni Kaiserslautern)
Modeling of Hybrid Electric Vehicles in Modelica for
 Virtual Prototyping (Uni Gothenburg)
The Modelica Flight Dynamics Library (DLR)

                    SystemDesign
KTI-Projek Nr. 6225.1



Auflaufsimulation von Personen- und Güterzügen
Ziel: Modelica-Bibliothek zur Optimierung von Kupp-
 lungsvorgängen, Analyse des Schwingungsverhaltens
 und Beurteilung der Kollisionssicherheit
Umfang:
  – KTI-Beitrag:                     200‘000.-
  – Eigenleistung Schwab AG          260‘000.-
  – Eigenleistung LEC                 20‘000.-
  – Cash Schwab AG                    20‘000.-


                   SystemDesign

								
To top