Archived OpenModelica forums. Posting is disabled.

Alternative forums include GitHub discussions or StackOverflow (make sure to read the Stack Overflow rules; you need to have well-formed questions)


Forgot password? | Forgot username? | Register
Page Start Prev 1 Next End

Deriving Equations for Modelica

#5922  Permalink Top

Deriving Equations for Modelica

Jun-18-15 06:24:37

Hey,

I'm trying to simualte a basic DC motor in OpenModelica. I'm concerned with the Output angular speed of the motor on application of a certain load.
I have been able to simulate the model and get the curve for the output angular speed. Is there a possible way by which I can get the equation for the the speed?
( What I'm trying to find is the dependecies of angular speed in terms of voltage applied,resistance,moment of inertia etc. in form of an equation)


Thanks

#5924  Permalink Top

Re: Deriving Equations for Modelica

Jun-18-15 06:36:08

Thanks for the answer.
But, I didn't really get the solution. I couldn't find the representative equation for the speed.
I would really appreciate if you could help.

Thanks

Edited by: smaug - Jun-18-15 07:11:12
#5925  Permalink Top

Re: Deriving Equations for Modelica

Jun-18-15 06:41:44

You look for the variable that you plot, double-click it. Double-click the equation that defines it, and it shows what OpenModelica uses to solve for the variable. If you need to expand one of the variables on the rhs, do so manually by looking up those variables as well. You can only really get the statements that OpenModelica used to solve the system without processing the information.

#5926  Permalink Top

Re: Deriving Equations for Modelica

Jun-18-15 07:05:38

Well, Thanks

But the only equation I can see is dcpm.RotorInertia.w= $_start(dcpm.RotorInertia.w)
How do I get its dependency on Voltage(V), Inertia(J) etc.

#5927  Permalink Top

Re: Deriving Equations for Modelica

Jun-18-15 07:29:40

Look for the regular equation of the derivative of the variable. State variables have no equations except for the initial value.

#5932  Permalink Top

Re: Deriving Equations for Modelica

Jun-19-15 15:34:26

I am sorry, but this didn't work either.

the equation I found was der(dcpm.InertiaRotor.w)=Inertia1.a
However, Inertia1.a variable cannot be accessed.

I mean when I try to find Inertia1.a on the list on the left side, the variable is not accesible

Page Start Prev 1 Next End
Previous topic
Next topic
There are 0 guests and 0 other users also viewing this topic
You are here: