Thread Subject: simscape simulation

i am running a simulation on pv using the simscape,

i think my model is correct.

Then this message's error show up

"Trouble solving algebraic loop containing 'pv_char_1/MATLAB Fcn' at time 0.001. Stopping simulation. There may be a singularity in the solution. If the model is correct, try reducing the step size (either by reducing the fixed step size or by tightening the error tolerances)"


what does it meant?

how can i solve it?

"Tan Chin Yew" <hayview@gmail.com> wrote in message
news:iognlc$ssb$1@fred.mathworks.com...
> i am running a simulation on pv using the simscape,
>
> i think my model is correct.
>
> Then this message's error show up
>
> "Trouble solving algebraic loop containing 'pv_char_1/MATLAB Fcn' at time
> 0.001. Stopping simulation. There may be a singularity in the solution. If
> the model is correct, try reducing the step size (either by reducing the
> fixed step size or by tightening the error tolerances)"
>
>
> what does it meant?
>
> how can i solve it?

It means that you have an algebraic loop in your model and the solver can't
solve it. It's difficult to comment any further without seeing the model,
but it seems that you are using a "MATLAB Fcn" block in your model. I would
strongly advise against doing this. This calls into the MATLAB engine at
each time step and is very inefficient. What solver are you using, with
which tolerances? You can find general recommendations on how to deal with
algebraic loops in the Simulink documentation:
http://www.mathworks.com/help/toolbox/simulink/ug/f7-8243.html#f7-19688

If your loops stay within the Simscape environment, then you won't have any
algebraic loops:
http://www.mathworks.com/help/toolbox/physmod/simscape/ug/bqqjdvg-1.html#bqqjdvg-4

HTH,

Arnaud