Matlab help (Root Locus using Z Domain)

[Ethers0n]

I'm trying to prooduce a plot of a root locus for an open loop transfer function.
The transfer function is in the z-domain, with a gain K. I've already solved for the charectoristic equation of the system by hand.

But, how do I use Matlab to plot the root locus of a transfer function in the Z - Domain? I've seen examples in the Laplace (s) Domain...do these work the same way? (as in...i won't need to do anything differently?)

thank you.

 

[SGT]

When describing your system in Matlab you must inform the sampling time. Matlab will automatically know that you are using a discrete variable. The command rlocus will draw your root locus for your z variable.

 

[tacman]

Hi there,

Thank you for reaching out for help with plotting a root locus in the z-domain using Matlab. The process for creating a root locus plot in the z-domain is similar to that in the Laplace (s) domain, but there are a few differences to keep in mind.

First, let's briefly review the steps for generating a root locus plot in Matlab:

1. Define the transfer function in either the s-domain or z-domain.
2. Use the 'rlocus' function to generate the root locus data.
3. Plot the root locus using the 'plot' function.

Now, for the z-domain specifically, there are a few things to consider:

1. The 'rlocus' function in Matlab only accepts transfer functions in the s-domain. Therefore, you will need to convert your z-domain transfer function to the s-domain before using the 'rlocus' function. This can be done using the 'c2d' function in Matlab, which converts a continuous-time transfer function to a discrete-time transfer function.
2. Once you have converted your transfer function to the s-domain, you can proceed with generating the root locus data and plotting it using the 'rlocus' and 'plot' functions as usual.

I hope this helps you get started with plotting your root locus in the z-domain using Matlab. If you need further assistance, I recommend consulting the Matlab documentation or reaching out to their support team for more specific guidance.

Best of luck with your project!