Part b) A simplified process control block diagram is shown as: XF(S) MS) Gl(s) wt% %TO R(S) E(S) Ms) C(s) G(s) Gp(s) %TO %TO %CO %TO %TO C(s) %TO Where: = R(s) = setpoint E(s) = R(s) C(s) M(s) = controller output C(s) = measured variable GP(s) = process transfer function XF(s) = change in inlet moisture Gl(s) = disturbance transfer function = The process transfer function and the disturbance transfer function were each approximated by a FOPDT model, so: Gp(s) Kpe-tops G(s) K e-tols TLS+1 Tp5+1 Where: top = the process deadtime, and tol = the disturbance deadtime. The figures below show the exiting moisture pebble wt% response (open loop) to an 8% step change in the controller output, and the exiting pebble moisture wt% response (open loop) to a disturbance step change of a 3 wt% moisture increase in the feed, respectively. 5.0 - 5.0- 4.5 4.5 4.0 4.0 Moisture, % Moisture, % 3.5 3.5 3.0 3.0 0 50 400 0 50 100 150 200 250 300 350 400 Time, s 1 100 150 200 250 300 350 Time, s Exiting pebble moisture (wt%) responding to a step change in the controller output of an 8% incr. Exiting pebble moisture (wt%) response to a step change incr of the entering pebble moisture concentration of 3 wt%. From the graphs the following FOPDT values were found: %TO Kp = 4.688 %CO Tp = 120 sec top = 70 sec %TO K= 16.67 wt% Ti = 105 sec ToL = 65 sec b) (71.4%) Determine the PI tuning parameters for this process using the IMC method for aggressive tuning. Show your work. Include the units on the PI tuned constants