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Integration method and time step of exported FMU

Integration method and time step of exported FMU

Is there a possibility to set the integration method and time step when exporting FMU as a co-simulation other than dassl?

Re: Integration method and time step of exported FMU

The only integration method you can set for co-simulation FMUs is Euler. Dassl is not supported.

Re: Integration method and time step of exported FMU

Thanks for the feedback.

I have noticed that in ModelName_init_fmu.c the solverMethod always set to "dassl".

From model annotation such as

Code:


annotation(
    Icon(coordinateSystem(preserveAspectRatio = false)),
    Diagram(coordinateSystem(extent = {{-180, -180}, {180, 180}})),
  experiment(StartTime = 0, StopTime = 1E8, Tolerance = 1e-06, Interval = 0.001),
  __OpenModelica_commandLineOptions = "--matchingAlgorithm=PFPlusExt --indexReductionMethod=dynamicStateSelection -d=initialization,evaluateAllParameters,NLSanalyticJacobian -d=initialization ",
  __OpenModelica_simulationFlags(lv = "LOG_STATS", outputFormat = "csv", s = "euler"));

the values that written in ModelName_init_fmu.c are the one under experiment annotation (startTime, stopTime etc). That's why i was wondering why it was always defaulted to dassl.

Re: Integration method and time step of exported FMU

sjoelund.se wrote:


The only integration method you can set for co-simulation FMUs is Euler. Dassl is not supported.

Hi Martin,

is the Step size in FMU set a a default value (e.g. 0.001s) or can we define it via annotation?

Thanks

Re: Integration method and time step of exported FMU

As far as I can tell it simply uses the communicationStepSize sent to it by the master algorithm. It will not try to take smaller steps than that.

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