PID Ti and Td

[FaustoTromba]

Hi

I have never used PID before and for me it's not clear what is Ti and Td in minute. I've read a lot about it but not enough likely.

My cycle loop is 20 ms. My Kp is about 0.05556 and now i should set the Ti and Td in minute (60 seconds). how can I caluculate them?

Thanks in advance

Fausto

[GerdW]

Hi Fausto,

have you read the Wikipedia (or any good book) on PID controls?

Have you heard about Ziegler and Nichols?

[FaustoTromba]

Hi, 

yes i've read. I've read also this interesesting manual

http://experimentationlab.berkeley.edu/sites/default/files/PID_Manual.pdf.

Despite it, i don't find my reply to my issue.

[GerdW]

Hi Fausto,

now i should set the Ti and Td in minute (60 seconds). how can I caluculate them?

One way to determine (aka "calculate") them is to apply Ziegler-Nichols. Did I mention that before?

Or don't you know how to convert a value with unit "second" to a value in unit "minute"?

[Yamaeda]

So, according to ZG, what's your self oscillating period?

/Y