Real-Time Performance Evaluation of a Fuzzy PI + Fuzzy PD Controller for Liquid-Level Process

Abstract

In this paper, a comparative study was carried out to evaluate the real-time performance of fuzzy proportional-integral plus fuzzy proportional-derivative (Fuzzy PI + Fuzzy PD) controller with the real-time performance of Conventional PI for a liquid-level process experiment. The process considered for this experiment shows highly nonlinear behavior due to equal percentage pneumatic control valve. NATIONAL INSTRUMENTS™ based hardware and software tools (LabVIEW™) were used for precise and accurate acquisition, measurement and control. The real time implementation of the Fuzzy PI + Fuzzy PD controller was carried out in two configurations: namely, feedback and cascade. In cascade control configuration Fuzzy PI + Fuzzy PD controller was implemented in the primary loop. The secondary loop was tuned using the conventional PI controller. It was evaluated that Fuzzy controller perform better in comparison with conventional controller in both the feedback and cascade control configurations.