Opened 8 years ago

Last modified 7 years ago

#4237 closed defect

Bad treatment of algebraic loops in synchronous models — at Version 1

Reported by: Rüdiger Franke Owned by: Lennart Ochel
Priority: high Milestone: 1.13.0
Component: Backend Version: v1.12.0
Keywords: Cc: Willi Braun, Bernhard Thiele, Patrick Täuber

Description (last modified by Rüdiger Franke)

​PR1391 along with ​commit d32ecb make ControlledMixingUnit work by applying index reduction and appropriately implementing ExplicitEuler, respectively.

Some more issues show up when replacing ExplicitEuler with ImplicitEuler, introducing algebraic loops. See the following example:

model ControlledMixingUnit2
  extends Modelica_Synchronous.Examples.Systems.ControlledMixingUnit(
    periodicClock1(solverMethod="ImplicitEuler"));
end ControlledMixingUnit2;

No Jacobians and no ModelStructure are generated!

Moreover, there is a linear torn system of dimension 1 -- shouldn't this be solved analytically?

Last but not least, the C runtime does not generate code for algebraic loops in clocked partitions.

Change History (1)

comment:1 by Rüdiger Franke, 8 years ago

Description: modified (diff)
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