Asked by Siyu He
on 16 Aug 2013

I am tring to express ZOH transfer funcation in S domain and bode plot it. The transfer functino is shown below:

(1-exp(-s*Ts))/s

The question is how to express it, is there any function related to it?

Thanks.

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Answer by Arkadiy Turevskiy
on 20 Aug 2013

Accepted answer

s=tf('s'); Ts=0.1 %replace with desired value sys=(1-exp(-s*Ts))/s bode(sys)

Siyu He
on 20 Aug 2013

Thanks for your reply. I tried this method and error information shown below,

??? Error using ==> InputOutputModel.plus at 61 System interconnection gives rise to internal delays and can only be represented in state space. Convert at least one of the models to state space using the "ss" command.

Error in ==> InputOutputModel.InputOutputModel>InputOutputModel.minus at 324 M = M1 + (-M2);

P.S. I am using Matlab R2010b version.

Arkadiy Turevskiy
on 21 Aug 2013

In 10b:

s=tf('s'); Ts=0.1 sys1=exp(-Ts*s)/s sys2=1/s sys=ss(sys2)-ss(sys1); bode(sys)

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## 6 Comments

## Azzi Abdelmalek (view profile)

Direct link to this comment:http://www.mathworks.com/matlabcentral/answers/84949#comment_164708

The link do not contain your block

## Azzi Abdelmalek (view profile)

Direct link to this comment:http://www.mathworks.com/matlabcentral/answers/84949#comment_164709

Your question is not clear

## Siyu He (view profile)

Direct link to this comment:http://www.mathworks.com/matlabcentral/answers/84949#comment_164710

I just replace the image by symbolic expression. Please take a look.

## Siyu He (view profile)

Direct link to this comment:http://www.mathworks.com/matlabcentral/answers/84949#comment_164711

May I know what should I do to make it clear?

## Azzi Abdelmalek (view profile)

Direct link to this comment:http://www.mathworks.com/matlabcentral/answers/84949#comment_164713

Which image?

## Siyu He (view profile)

Direct link to this comment:http://www.mathworks.com/matlabcentral/answers/84949#comment_164715

I don't know how to upload image and the tf is shown by symbolic expression now.