PID transfer functions


Thread Starter

Alexander Sánchez

Dear Sirs,

I am starting to work on my Thesis to obtain a Bachelor Degree on Electrical Engineering at the University of Costa Rica.

As part of my research I need to obtain information on the “real” PID transfer functions of the industrial commercial controllers
(pneumatic, electronic: analog and digital, in DCS and control software, etc.) and to classify them as “ideal”, “interacting”, “industrial”, etc.

I truly will appreciate your assistance in obtaining this information for your PID controllers and/or any reference to a source on
commercial PID controllers comparison.

I look forward to receive your information at your earlier convenience at any of the following addresses:

e-mail: [email protected]

Air mail delivery: 4050 -– 862 (Alajuela - Costa Rica)

Street address (only for courier delivery): 300mts to south from the school Manuel Fco. Carrillo and 100mts to North

Thank you in advance for your help.

Best regards,

Alexander Sánchez
The first 159 pages of Volume 2 of the Instrument Engineers' Handbook (IEH) deals with all the different types of PID configurations, incuding digital implementations in PLCs and DDC systems, their algorithms, transfer functions, tuning, etc.

All technical libraries have the IEH, I'm sure you you will find it in your university library.

Best regards,

Béla G. Lipták, P.E., Consultant and editor
84 Old N. Stamford Rd., Stamford, CT. 06905-3961
Tel: 203-357-7614, Fax: 203-325-3922
E-Mail: [email protected]

One of the best reference sources is the help files for AEG Schneider's (Modicon) Concept programming software. In the help you will find 3 implementations of the PID along with the LaPlace transforms and the difference equations.

Contact AEG Schneider. They have a demo version of the Concept software from which you can access the help files.