Page 227 - Mechatronic Components Roadmap to Design

Controls Theory and Applications Chapter 14 207

PV
Set point Change K u
changed until oscillations Constant
and K u increased are constant amplitude
to 3
oscillation obtained
200°C

K u increase
K u =3 again K u decrease ultimate P u = 10 sec
(not enough) K u =4 period
(too much) K u =3.5 K u =3.5
t (sec)
10 sec 20 sec
t 0 t 1 t 2