working with transfer function, overflow error

I am working with a transfer function that modelates a MIMO system of 15 inputs and 15 outputs. I have to perform the following operation:

H2=H/(A*H+B);

where H is the transfer function of the original system, A and B are scalar matrix of dimensions 15x15 and H2 is the transfer function that I want to obtain.

I have tried the command:

Hin=A*H+B;

H2=H/Hin;

but I obtain the following message: 'Unable to convert the model to a transfer function because of overflow'

Thanks in advance.

Answer 1

[Jamie]

Hi upna,

I note this post is rather old. I trust you've long since resolved the issue. In the off-chance.. in this situation I would usually look to obtain a minimal realisation with a suitable tolerance prior to the manipulation of H

i.e.

> minreal(H,tolerance)

In general, numeric LTI models are not ideal where accuracy is concerned. If poss a ss approach would be preferable

http://www.mathworks.com/help/control/ug/conversion-between-model-types.html