CHE 185 – PROCESS CONTROL AND DYNAMICS

1. CHE 185 – PROCESS CONTROL AND DYNAMICS WORKSHOP 3

2. P-Only Control of Jacketed Reactor Temperature • Objective • To design and test a P-Only controller for tracking changes in set point and rejecting disturbances. Also, to explore how controller gain impacts P-Only performance.

3. P&ID FOR WORKSHOP

4. P&ID FOR WORKSHOP

5. P-Only temperature control • reactor exit temperature (the measured process variable) of 91°C • PVsetpoint = • IN MANUAL MODE, movE the controller output signal until the measured variable reads 91°C • CObias =

6. P-Only temperature control • Compute and record the FOPDT process model parameters: • Process gain, Kp= • Time constant, τp = • Dead time, θp =

7. P-Only temperature control • the ITAE (Integral Time Weighted Absolute Error) design correlation for Set Point Tracking

8. P-Only temperature control • changing your controller gain to search for a performance that balances offset against oscillatory behavior. Call this your "best“ KC: • “Best” KC =

9. TYPICAL RESULTS • The set point should be at the design level of the measured process variable: • pvsetpoint = 91 oC • A P-Only controller design requires the controller bias. : • ubias = 45% • FOPDT process model parameters: • Process gain, KP = - 0.33 oC/% • Time const, P = 2.1 min • Dead time, P= 0.5 min

10. TYPICAL RESULTS

11. TYPICAL RESULTS

12. TYPICAL RESULTS

13. TYPICAL RESULTS • ITAE for Set Point Tracking tuning relation: • KC = - 3.52 %/oC

14. TYPICAL RESULTS • USE CALCULATED PARAMETERS TO ACTIVATE AUTOMATIC CONTROL. enter Set Point, Bias and Controller Gain:

15. TYPICAL RESULTS

16. TYPICAL RESULTS step the set point from 91 to 95 to 99 to 103 oC

17. TYPICAL RESULTS