Title :
Synthesis of a robust pH controller using QFT
Author :
Barve, J.J. ; Nataraj, P.S.V.
Author_Institution :
Dept. of Syst. & Control Eng., Indian Inst. of Technol., Mumbai, India
Abstract :
The robust regulatory controller for the highly nonlinear pH process is synthesized using the non-linear equivalent disturbance attenuation (NLEDA) technique of quantitative feedback theory (QFT). In the considered pH process, a strong acid flows into the constant volume well mixed tank and is thoroughly mixed with the strong base whose flow rate is manipulated to neutralize the outlet from the tank. The controller is designed to regulate the pH of the outlet stream within (7.0±0.2) in the presence of significant parameter uncertainties and load disturbances. The robust stability of the control system is guaranteed by the QFT design procedure. The robust performance of the proposed controller is evaluated by rigorous simulation studies with the help of the nonlinear process model. The effects of sensor noise and random disturbances on the controller performance are also studied. The results are found to be very good
Keywords :
chemical sensors; controllers; feedback; frequency-domain synthesis; noise; pH control; robust control; QFT; acid; control system; controller performance; flow rate; frequency domain design; load disturbances; nonlinear equivalent disturbance attenuation; nonlinear pH process; nonlinear process model; parameter uncertainties; quantitative feedback theory; random disturbances; robust pH controller synthesis; robust performance; robust regulatory controller; robust stability; sensor noise; simulation; Adaptive control; Continuous-stirred tank reactor; Control system synthesis; Feedback; Open loop systems; Programmable control; Robust control; Sliding mode control; Three-term control; Uncertain systems;
Conference_Titel :
TENCON '98. 1998 IEEE Region 10 International Conference on Global Connectivity in Energy, Computer, Communication and Control
Conference_Location :
New Delhi
Print_ISBN :
0-7803-4886-9
DOI :
10.1109/TENCON.1998.797124
