Design and Implementation of Adaptive Fuzzy Knowledge Based Control of pH for Strong Acid-Strong Base Neutralization Process

  • Parikshit Kishor Singh Indian Institute of Information Technology Kota, MNIT Jaipur campus
  • Surekha Bhanot Department of EEE, BITS Pilani, Pilani, 333031, India
  • Hare Krishna Mohanta Department of Chemical Engineering, BITS Pilani, Pilani, 333031, India
  • Vinit Bansal Field Consultant, National Instruments, Bengaluru, India
Keywords: strong acid-strong base neutralization process, nonlinear process, pH control, fuzzy knowledge based control, adaptive control, intelligent control


pH control is a benchmark for control of nonlinear processes because of its importance in number of industrial process applications. Fuzzy Knowledge Based Control (FKBC) of such nonlinear processes incorporates the method for constructing nonlinear controllers using heuristic experience. This paper describes design and implementation of adaptive FKBC for a pH neutralization process consisting of strong acid (Hydrochloric acid, HCl) and strong base (Sodium Hydroxide, NaOH) streams in the multifunctional Process Control Teaching System (PCT40) with Process Vessel accessory (PCT41) and pH Probe accessory (PCT42) of Armfield® Ltd., United Kingdom. The adaptive FKBC modifies fuzzy universe of discourse by using adaptive gain matrix based on error and change in error. The adaptive FKBC has been found to operate over wide range with satisfactory performance. Results of adaptive FKBC for servo and regulatory operations have been compared with optimized fuzzy logic control schemes. The pH neutralization system is interfaced with Laboratory Virtual Instrumentation Engineering Workbench (LabVIEW®) for experimental validation of results.

Author Biography

Parikshit Kishor Singh, Indian Institute of Information Technology Kota, MNIT Jaipur campus
Assistant Professor, Department of ECE


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