I am currently developing a large and complex thermo-hydraulic systems in Modelica/Dymola environment using ThermoPower library by Prof. Francesco Casella. At present, I have completed building our system model (which contains several closed-loop hydraulic circuits) and concentrating on designing controllers for the developed model. Given complexity of the system, I have about 25 PI controllers controlling various valve opening, pump, condenser and boilers. At this stage, I am tuning the controller gains using some judicious trial-and-error method. I tried to look into literature to see if there are any formal design methodology or any rule-of-thumbs for designing controllers for such a multi-input-multi-output (MIMO) thermo-hydraulic system. Consequently, I would like to ask if anyone can provide some pointers or literature/papers which deals with controller designs for such systems. Because my knowledge in controller design (sliding mode, linear control, root locus, etc) are not helping me here as most of these methodology are based on available model equations.

Furthermore, for such a large thermo-hydraulic systems, how one sets initial conditions of the system? Does one need to just provide some reasonable guess value and expect Dymola to take care of rest of it?

I apologize if you have seen this question somewhere else.

Thanks

JG

Hi all,

I was wondering if anyone is aware of any manual available for SPOT library, other then that comes with the library? I am a newbie and I want to learn power system modeling. I was trying to understand what theoretically happening with transient modeling in power systems? Which reference book is recommended for understanding the physics/theory behind SPOT library?

Thanks
JG

Hi everyone,

I was wondering if there is any archives from where I can download older version of Dymola?

Thanks

Hi everyone:

I am wondering how can I access the gamma (ratio of heat capacity) for water using Modelica.Media? Can somebody give me an example of the syntax? I am attaching a pseudo-code of what I am trying to achieve?

Thanks
JG

model test1

  replaceable package Medium = Modelica.Media.Water.StandardWater constrainedby 

    Modelica.Media.Interfaces.PartialMedium "Medium model";

Modelica.SIunits.RatioOfSpecificHeatCapacities gamma ;



 Modelica.Fluid.Interfaces.FluidPort_a port_a(   redeclare package Medium = Medium,   m_flow(min=if allowFlowReversal then -Constants.inf else 0)) 



 Modelica.Fluid.Interfaces.FluidPort_b port_b(    redeclare package Medium = Medium,    m_flow(min=if allowFlowReversal then -Constants.inf else 0)) 



.....



equation

gamma=Medium.isentropicExponent(port_a.ThermodynamicState)  //??????????????????

......

end test1

Dear All,
I was wondering if anyone has implemented external media library +fluidprop in openmodelica and know the know -hows.
Thanks
JG

I want to know if anyone has had this problem. I am trying to compile Modelica.Mechanics.MultiBodyExamples.Systems.RObotR3.fullRobot and it takes a long time to compile and the simulation does not start.

Thanks
JG

I have noticed that Modelica has found more acceptability in European countries than North American countries. Look at the member list on Modelica Association. Does anyone has an opinion on why it is so?

Hi,
This is not the appropriate forum, but can I misuse the liberty to ask "how add a modelica library in Dymola demo 7?"
Thanks
JG

On another note, there is no display of an example provided by ThermoPower. I think this is related to the fact that THermoPower is built with M 2.2.2.


Which version of OM implemented Modelica 2.2.2? May be I would install that? Just curious, can I have two seperate versions of OM on my windows machine?

Thanks
JG

Thanks, Adeel. That worked. I can see the library appearing in the library pane. however, I get all these messages...As I am just one day baby in terms of OM, I am hoping this is something that is not source of major problem and can be avoided..

Thanks
Jadoogar
.................................................


Translation    20:53:20    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/PowerPlants.mo

    17074:9-17077:26    connect(Shaft_b, Shaft_b) connects the same connector instance! The connect equation will be ignored.

Scripting    20:53:20        0:0-0:0    Requested package Modelica of version 2.2.2, but this package was already loaded with version 3.1. You might experience problems if these versions are incompatible.

Syntax    20:53:20    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Test.mo    6321:17-6321:19    Treating .5 as 0.5. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.

Syntax    20:53:20    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Test.mo    6317:17-6317:19    Treating .5 as 0.5. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.

Syntax    20:53:20    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Test.mo    6285:17-6285:19    Treating .6 as 0.6. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.

Syntax    20:53:20    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Test.mo    6280:17-6280:19    Treating .3 as 0.3. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.

Syntax    20:53:20    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Test.mo    6259:17-6259:19    Treating .5 as 0.5. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.

Syntax    20:53:20    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Test.mo    6170:17-6170:19    Treating .3 as 0.3. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.

Syntax    20:53:20    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Test.mo    6168:17-6168:19    Treating .8 as 0.8. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.

Syntax    20:53:20    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Test.mo    6164:16-6164:18    Treating .4 as 0.4. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.

Syntax    20:53:20    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Test.mo    6139:17-6139:19    Treating .3 as 0.3. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.

Syntax    20:53:20    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Test.mo    6137:17-6137:19    Treating .5 as 0.5. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.

Syntax    20:53:21    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Test.mo    6133:16-6133:18    Treating .4 as 0.4. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.
Syntax    20:53:21    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Test.mo    6010:17-6010:19    Treating .3 as 0.3. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.

Syntax    20:53:21    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Test.mo    5972:17-5972:19    Treating .3 as 0.3. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.
Syntax    20:53:21    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Test.mo    5819:17-5819:19    Treating .2 as 0.2. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.
Syntax    20:53:21    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Test.mo    5738:17-5738:19    Treating .3 as 0.3. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.
Syntax    20:53:21    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Test.mo    5643:17-5643:19    Treating .3 as 0.3. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.
Syntax    20:53:21    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Test.mo    5519:38-5519:41    Treating .05 as 0.05. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.
Syntax    20:53:21    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Test.mo    5519:33-5519:36    Treating .05 as 0.05. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.
Syntax    20:53:21    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Test.mo    1147:17-1147:19    Treating .5 as 0.5. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.
Syntax    20:53:21    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Test.mo    117:17-117:19    Treating .2 as 0.2. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.
Syntax    20:53:21    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Test.mo    42:17-42:19    Treating .2 as 0.2. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.
Syntax    20:53:21    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Examples.mo    1965:19-1965:21    Treating .1 as 0.1. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.
Syntax    20:53:21    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Examples.mo    1921:19-1921:21    Treating .1 as 0.1. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.
Syntax    20:53:21    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Examples.mo    1799:19-1799:21    Treating .1 as 0.1. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.
Syntax    20:53:21    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Examples.mo    929:16-929:19    Treating .06 as 0.06. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.
Syntax    20:53:21    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Examples.mo    195:16-195:19    Treating .06 as 0.06. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.
Syntax    20:53:20    C:/OpenModelica1.8.1/lib/omlibrary/ThermoPower/Test.mo    6304:17-6304:19    Treating .3 as 0.3. This is not standard Modelica and only done for compatibility with old code. Support for this feature may be removed in the future.

Hi Adeel,
Do I still do the following change?
%%%%%%%%%%%
Also, add in the your library top package:
within Modelica;
package YourLibrary
end YourLibrary;

%%%%%%%%%%%%%%

Moreover, thermopower uses Modelica.Media and as far as I understand that is not suported .. SO do you think it would work?

Thanks
Jadoogar

Hi,

I have a question regarding installing thermopower library in openmodelica (OMEdit). I was browsing through the older topics and found this

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

Well, as a workaround you can trick OMC to think your library is part of the Modelica library.
Add your library (directory or just Library.mo) to:
c:\OpenModelica1.6.0\lib\omc\omlibrary\msl31\Modelica
Also, add in the your library top package:
within Modelica;
package YourLibrary
end YourLibrary;


Cheers,
Adrian Pop/

%%%%%%%%%%%%%%%%%%

I think this work around is not valid any more. The paths are not what suggested in there. Can somebody help me? I have the latest version on OMEdit on a Mac OS X.

Thanks
Jadoogar