Quasi static fundamental wave machines are not simulating

[Christian Kral <dr.christian.kral@…>]

It is planned for MSL 3.2.2 to include further packages. One of these packages is the Modelica.Magnetic.QuasiStatic.FundamentalWave library. In order to test this library with MSL 3.2.1 I attached the package Modelica_AddOn, which includes all the new packages of MSL 3.2.2.

Please test the examples of Modelica_AddOn.Magnetic.QuasiStatic.FundamentalWave.Examples. None of these examples works the actual nightly build version of OpenModelica. I tested the examples with

• Ubuntu 14.04 32 bit
• OpenModelica 1.9.4~dev-155-ga69

When simulating the models I receive the following error messages:

Matrix singular!
under-determined linear system not solvable!

I wonder whether this issue is related with #3084.

[Christian Kral <dr.christian.kral@…>]

Modelica_AddOn

[anonymous]

Model Modelica_AddOn.Electrical.PowerConverters.Examples.ACDC.RectifierBridge2mPulse.HalfControlledBridge2mPulse lacks fully specified initial conditions.

[Anton Haumer <a.haumer@…>]

Dear Martin S., please have a look who at OpenModelica could take care of that ticket!

MSL 3.2.2 is released, containing Modelica.Magnetic.QuasiStatic.FundamentalWave.
Today I tested the attached Modelica_AddOn (based on MSL 3.2.1), with the latest release OpenModelica 1.9.6 on Windows 7 Professional 64 bit ServicePack 1, with the following result:
...
Matrix singular!
...
simulation terminated by an assertion at initialization
Simulation process failed. Exited with code -1.

It seems that for 6 months nothing happened. It would be a real pity if OpenModelica could not simulate those quasistatic machine models because OpenModelica is perfect for teaching, and it is perfect for demonstrating Modelica to interested industrial users.

In case of further questions, please do not hesitate to contact either the reporter (Christian Kral) or me (Anton Haumer).

[Adrian Pop]

See here:
​https://test.openmodelica.org/libraries/MSL_trunk/BuildModelRecursive.html
we can build all the models but some of them fail during simulation with issues in non-linear systems. You can try it with the latest nightly build:
​https://build.openmodelica.org/omc/builds/windows/nightly-builds/

[Anton Haumer <a.haumer@…>]

Please have a look at the examples uploaded by Christian: none of them simulates!
(Modelica_AddOn.Magnetic.QuasiStatic.FundamentalWave.Examples.BasicMachines)
Please bear in mind: those models only have a few states!
Electric quantities are calculated with Complex algebraic equations.
See the following message: Solving non-linear system xxx failed at time=0.

[Anton Haumer <a.haumer@…>]

The same experiment with a transient machine model (either from Modelica.Electrical.Machines or from Modelica.Magnetic.FundamentalWave) simulate - the problem seems to be related to solving complex algebraic equations (instead of solving real differential equations).

[Anton Haumer <a.haumer@…>]

Amazing: I changed some minor things in an example model (with a Magnetic.QuasiStatic.FundamentalWave machine model) that did not simulate yesterday, and today after these minor changes (I suppose only re-ordering the equations!) it simulates with the same nightly build as yesterday!
This reminds me of #3691 and #3649: solving the algebraic equation system of quasistatic machines is similar to solving the initial algebraic equation system of transient machine models.

[Anton Haumer <a.haumer@…>]

see #3636 (MSL v3.2.2-build.3-release was released 2016-04-03!)

[Christian Kral <dr.christian.kral@…>]

I tested the following examples with version 1.10.0~dev-103-g43d1b0b under Ubuntu 14.04 64bit.

IMC_DOL               m=3: OK    m=5 (default): FAILS   
IMC_Inverter          m=3: OK
IMS_Start             m=3: OK

SMPM_Mains            m=3: OK
SMPM_OpenCircuit      m=3: OK
SMPM_CurrentSource    m=3: OK
SMEE_Generator (*)    m=3: QS model OK, but transient model calculations are wrong 
SMR_CurrentSource     m=3: OK

(*) I compared the simulation results with Dymola where the physics of the generator is simulated correctly (see PNG attachments)

[Christian Kral <dr.christian.kral@…>]

SMEE_Generator result of OMEdit 1.10.0~dev-103-g43d1b0b

[Christian Kral <dr.christian.kral@…>]

SMEE_Generator result of Dymola 2016

[Christian Kral <dr.christian.kral@…>]

I forgot to mention that the tested examples refer to the MSL 3.2.2 release (build 3); see also ​https://test.openmodelica.org/libraries/MSL_trunk/BuildModelRecursive.html

[Christian Kral <dr.christian.kral@…>]

From my understanding the working simulations are related ticket:3649#comment:9

[Christian Kral <dr.christian.kral@…>]

To be more precise: the OMEdit version I tested the examples with is named:

1.10.0~dev-103-g43d1b0b
Connected to OpenModelica 1.10.0~dev-486-g8df1b36