Thread Subject: drifting parameters in Simulink

I am trying to build a simulink model using transfer functions, however one of the values of the tf is dependent on time. And I don't know how to deal with this. I'm not the most familiar with Simulink so any help would be appreciated.

One alternative would be to take a state space modeling approach. If you
can convert your transfer function into state space equations, then you
can implement this model using basic Simulink blocks (e.g., sum,
product, integrator, etc.), including the time varying component. Having
a time-varying element of the transfer function complicates the
conversion to state space a little since you can't simply use the tf2ss
command to get your system of equations.

-James

Caleb wrote:
> I am trying to build a simulink model using transfer functions, however
> one of the values of the tf is dependent on time. And I don't know how
> to deal with this. I'm not the most familiar with Simulink so any help
> would be appreciated.

Yeah I thought about that, but the fact that it is a high order transfer function, makes doing it by hand quite tough.



James Allison <james.allison@mathworks.com> wrote in message <ho82bg$bt5$1@fred.mathworks.com>...
> One alternative would be to take a state space modeling approach. If you
> can convert your transfer function into state space equations, then you
> can implement this model using basic Simulink blocks (e.g., sum,
> product, integrator, etc.), including the time varying component. Having
> a time-varying element of the transfer function complicates the
> conversion to state space a little since you can't simply use the tf2ss
> command to get your system of equations.
>
> -James
>
> Caleb wrote:
> > I am trying to build a simulink model using transfer functions, however
> > one of the values of the tf is dependent on time. And I don't know how
> > to deal with this. I'm not the most familiar with Simulink so any help
> > would be appreciated.