Advanced Process Control Lecture one 1 Syllabus Marking

ﺑﺴﻢ ﺍﻟﻠﻪ ﺍﻟﺮﺣﻤﻦ ﺍﻟﺮﺣﻴﻢ Advanced Process Control Lecture one 1 - Syllabus, Marking Scheme and Reference Books 2 - Introduction to Single Input – Single Output Control (SISO) - Feedback Control - Feedforward and Cascade Control Lecturer: M. A. Fanaei Ferdowsi University of Mashhad 1

Syllabus v Review of SISO control Ø Introduction to feedback control theory Ø Process modeling Ø Control valve characteristics Ø Types and modifications of PID controllers Ø Tuning of PID controllers (offline and online) Ø Discrete version of PID controllers Ø Dynamic simulation and control of chemical processes using MATLAB/SIMULINK 2

Syllabus v Advanced SISO control topics Ø Performance and robustness Ø Cascade control Ø Feedforward control Ø Ratio, Override and Selective Control Ø Predictive control (IMC and Smith predictor) Ø State-space model (Continuous and Discrete) 3

Syllabus v MIMO control topics Ø Centralized and decentralized control Ø Interaction and relative gain array Ø Design of static and dynamic decoupler Ø Predictive control (DMC) 4

Marking Scheme & Reference Books v Marking scheme Ø Ø Ø Mid-term exam: Final exam: Homework: 35% 40% 25% v Reference books Ø C. A. Smith and A. Corripio, Principles and Practice of Automatic Process Control, 3 rd edition, Wiley, 2006. Ø K. J. Astrom and T. Hagglund, Advanced PID Control, ISA, 2006. Ø T. E. Marlin, Process Control: designing processes and control systems for dynamic performance, 2 nd edition, Mc. Graw-Hill, 2000. Ø K. Ogata, Modern Control Engineering, 3 rd edition, Mc. Graw-Hill, 1997. Ø K. J. Astrom and B. Wittenmark, Computer Controlled Systems, 3 rd edition, Prentice Hall, 1997. Ø C. C. Yu, Autotuning of PID controllers: A relay feedback approach, 2 nd edition, 5 Springer, 2006.

Control objectives and structures Safety Environmental protection Equipment protection Smooth plant operation and production Product quality Profit optimization Structures Feedback Feedforward Feedback/Feedforward Cascade Objectives 6

Feedback control Final Control Element Controller Sensor Transmitter Controller Final element Sensor Controlled variable Manipulated variable Process Disturbances Other outputs 7

Advantages and disadvantages of feedback control Disadvantages • Very simple technique • Effective for all disturbances • Provides zero ss offset • Works with minimum knowledge of the process • Does not take control action until the process output has deviated from set point • Affects the closed-loop stability Advantages 8

Feedforward control 9

Advantages and disadvantages of feedforward control Disadvantages • Compensates for a disturbance before the process output is affected • Does not affect the stability of the control system • Can not eliminate steady-state offset • Requires a sensor and model for each disturbance Advantages 10

Feedback / feedforward control 11

Cascade Control v When the simple feedback control structure don’t have an acceptable performance, a cascade structure may improve the performance (speed up the closed loop response). v A cascade structure can be used, when a process has some series dynamics and the output variables between theses dynamics can be measured. 12

Cascade Control (a process example) 13

Cascade Control (a process example) 14