model produces unexpected results...

[dohmp]

the following model and commands produce unexpected results using the shell:

---

clear()

cd("c:\temp")

loadModel(Modelica)

model diodeTest

Modelica.Electrical.Analog.Sources.SineVoltage

vs1(V=10.0,phase=0,freqHz=60,offset=0,startTime=0);

Modelica.Electrical.Analog.Basic.Ground g;
Modelica.Electrical.Analog.Basic.Resistor r1(R=10);
Modelica.Electrical.Analog.Basic.Resistor r2(R=10);
Modelica.Electrical.Analog.Sources.ConstantVoltage vs2(V=4.0);
Modelica.Electrical.Analog.Sources.ConstantVoltage vs3(V=0.6);
Modelica.Electrical.Analog.Ideal.IdealDiode d1();

equation

connect (vs1.n,g.p);
connect (vs1.p,r1.p);
connect (r1.n,vs3.n);
connect (vs3.p,d1.n);
connect (d1.p,vs2.p);
connect (vs2.n,g.p);
connect (r1.n,r2.p);
connect (r2.n,g.p);

end diodeTest;

simulate(diodeTest,startTime=0,stopTime=0.025,numberOfIntervals=1000)

plot(r2.p.v)

---

the plot suggests that the ideal diode model is not actually setting the current
to zero on negative bias of the diode, even though all documentation and model
code suggests it should.

am i just an idiot, and somehow designed the circuit incorrectly? working it by
hand definitely produces a very different result.

[Peter Aronsson]

Added graphical annotations and verified that bug still exists:

model diodeTest

Modelica.Electrical.Analog.Ideal.IdealDiode d1

annotation(Placement(visible=true,transformation(x=-37.5,y=52.5,scale=0.075)));

Modelica.Electrical.Analog.Basic.Ground g

annotation(Placement(visible=true,transformation(x=-30,y=-10.8667,scale=0.075)));

Modelica.Electrical.Analog.Sources.SineVoltage

vs1(V=10.0,freqHz=60,offset=0,phase=0,startTime=0)
annotation(Placement(visible=true,transformation(x=-39.9521,y=16.65,scale=0.075,rotation=270)));

Modelica.Electrical.Analog.Sources.ConstantVoltage vs2(V=4.0)

annotation(Placement(visible=true,transformation(x=-60,y=27.1812,scale=0.075,rotation=270)));

Modelica.Electrical.Analog.Sources.ConstantVoltage vs3(V=0.6)

annotation(Placement(visible=true,transformation(x=-12.4354,y=52.5,scale=0.075,rotation=1080)));

Modelica.Electrical.Analog.Basic.Resistor r1(R=10)

annotation(Placement(visible=true,transformation(x=-13.1479,y=32.5249,scale=0.075)));

Modelica.Electrical.Analog.Basic.Resistor r2(R=10)

annotation(Placement(visible=true,transformation(x=5.9125,y=15,scale=0.075,rotation=270)));

equation

connect(vs3.n,r1.n)

annotation(Line(visible=true,points={{-5.02708,52.6333},{5.82083,52.6333},{5.82083,32.525},{-5.82083,32.525}}));

connect(r2.n,g.p)

annotation(Line(visible=true,points={{5.83958,7.52187},{5.83958,-3.32604},{-30.0115,-3.32604}}));

connect(r1.n,r2.p)

annotation(Line(visible=true,points={{-5.66979,32.525},{5.83958,32.525},{5.83958,22.4708}}));

connect(vs1.p,r1.p)

annotation(Line(visible=true,points={{-39.9521,24.0583},{-39.9521,32.525},{-20.6375,32.525}}));

connect(vs3.p,d1.n)

annotation(Line(visible=true,points={{-20.1083,52.6333},{-30.1625,52.6333}}));

connect(d1.p,vs2.p)

annotation(Line(visible=true,points={{-44.9792,52.6333},{-60.0604,52.6333},{-60.0604,34.6417}}));

connect(vs2.n,g.p)

annotation(Line(visible=true,points={{-60.0604,19.825},{-60,-3.45833},{-30.1625,-3.45833}}));

connect(vs1.n,g.p)

annotation(Line(visible=true,points={{-39.9521,9.24167},{-39.9521,-3.45833},{-30.1625,-3.45833}}));
end diodeTest;

[Jens Frenkel]

I checked the Model with Modelica 3.1 and compared it with dymola. There are no diverences.