-------- In message <[email protected]>, Didier Juges write s: >Without a D term, PI loops can be unstable when the gain (P) is >increased. If you will, with a large error, the correction will >itself be large and as the system corrects itself, it may overshoot >the target value, going into a low (or high if you really blew it) >level oscillation around the target value. The D term slows it >down just enough and minimizes that overshoot while maintaining a >high gain (low steady state error) and a fast response.
Before anybody gets any ideas that causes them to waste a lot of time: D terms are themselves very temperamental because they, by definition, amplify measurement jitter noise. In the precision time/frequency domain, D-terms are almost never realiastic. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 [email protected] | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
