How can I use some model as part of a different model? - modelica

Question

I write modeling program as part of diploma and I look for Modelica as input language.
But In the standard specification I can't find how to realize that feature:
For example I have some model:
model circuit1
Resistor R1(R=10);
Capacitor C(C=0.01);
Resistor R2(R=100);
Inductor L(L=0.1);
VsourceAC AC;
Ground G;
equation
connect (AC.p, R1.p);
connect (R1.n, C.p);
connect (C.n, AC.n);
connect (R1.p, R2.p);
connect (R2.n, L.p);
connect (L.n, C.n);
connect (AC.n, G.p);
end circuit1
How can I use this model as part of a different model?
Like that:
model circuit2
Resistor R1(R=10);
circuit1 circ(); // ! Define some circuit1
Resistor R2(R=100);
Inductor L(L=0.1);
VsourceAC AC;
Ground G;
equation
connect (AC.p, R1.p);
connect (R1.n, C.p);
connect (circ.somePin1, AC.n); // ! Connect circuit1 pins
connect (R1.p, R2.p);
connect (R2.n, L.p);
connect (L.n, circ.somePin2); // ! Connect circuit1 pins
connect (AC.n, G.p);
end circuit2
Edit
model circuit1
extends somePin1; //
extends somePin2; //
Resistor R1(R=10);
Capacitor C(C=0.01);
Resistor R2(R=100);
Inductor L(L=0.1);
VsourceAC AC;
Ground G;
equation
connect (AC.p, R1.p);
connect (R1.n, C.p);
connect (C.n, AC.n);
connect (R1.p, R2.p);
connect (R2.n, L.p);
connect (L.n, C.n);
connect (AC.n, G.p);
connect (AC.n, somePin1); //
connect (R1.n, somePin2); //
end circuit1

Answer 1

Apart from semicolons missing (end circuit2;), the code parses fine and is a correct way to create a composite Modelica model.

Answer 2

It seems to me, your question could be rephrased as:
How can I make a model so that other components can be connected to it?
If so, the key is to modify your original model (as Martin suggested) to look like this:
model circuit1
Resistor R1(R=10);
Capacitor C(C=0.01);
Resistor R2(R=100);
Inductor L(L=0.1);
VsourceAC AC;
MyPin somePin1; // Add some external connectors for
MyPin somePin2; // models "outside" this model to connect to
Ground G;
equation
connect (somePin1, AC.p); // Indicate where the external models
connect (somePin2, AC.n); // should "tap into" this model.
connect (AC.p, R1.p);
connect (R1.n, C.p);
connect (C.n, AC.n);
connect (R1.p, R2.p);
connect (R2.n, L.p);
connect (L.n, C.n);
connect (AC.n, G.p);
end circuit1;
Now I think you can use circuit2 exactly as you wrote it in your question.
A few additional comments:
It isn't clear if you are using the Resistor model in the Modelica Standard Library or your own Resistor model. If you are using the Modelica Standard Library, then replace "MyPin" with "Modelica.Electrical.Analog.Interfaces.PositivePin" (I think that is the name).
Models in Modelica start with capital letters by convention. So to make your model more readable to others, I would suggest renaming your models "Circuit1" and "Circuit2".
Don't forget the semicolons at the ends of the models (as Martin also pointed out).
You definitely DO NOT want to use extends as you have done in your edit. You need to add the pins to your diagram just as you have done with the resistor, ground, etc.
I hope that helps you understand things a bit better.