Auto Regressive Model

Perhaps it's just a good indication that you SHOULD HAVE DONE your homework, much earlier.

It is really tedious having the same people asking question they should know, or know how to solve themselves.

Your previous posts all indicate that you are a student. Statements referring to text books and exams are a sure indicator that you ARE a student. Not a very good one, at that, or you could do your own homework.

I'm keenly curious to know where you work, if this is not homework. I'm not sure that your employer is aware of your use of total strangers to help you perform your duties.

I beg your pardon again.

This was not a homework and I had some difficulty in understanding the concepts, but this wont happen again.

Thanks once again for your concern.

You are welcome.

There are many here who may be willing to help you.

Good luck.

Maybe this will help you in some way....

http://www.pacontrol.com/download/Process%20Control%20Fundamentals.pdf

You are correct in assuming gain will not be affected if the AR modeling does not capture the PV-SP offset.

If the AR model does not see the offset it also will not alter the Integral or Derivative which is a critical part of loop tuning.

Most robust modeling software packages have the ability for the operator to inject and/or manipulate different test parameters to observe system control reaction over a broad range of operating conditions.

If the system you are using does not have this capability I would upgrade it or scrap it and obtain a full-blown version modeling package.

It may be that AR has the capability to do all that you require for your modeling but you are not aware of where or how to implement it.

An in-depth review of the operating (IOM) documentation should reveal all capabilities as well as an instruction set on execution.

If you do not have all documentation or the documentation does not contain all instructions and answers to your questions, I would suggest you contact the AR tech support and ask them what you can do about the issue(s).

If they are not willing to help or their software is not capable of meeting your needs I would pursue purchasing a package from a different source that meets your requirements.

hi ,

I am using any package for AR modelling. I am using least squares method for calculating coefficients of AR model.

PID perhaps.