Fuzzy Adaptive PID Control of a Shell and Tube Heat Exchanger Output Temperature

This paper presents the design and the performance comparison of a classic PID controller, a feedforward PID controller, and a fuzzy PID controller. These controllers have been implemented to control the outlet temperature of a shell and tube heat exchanger. The controller with feedforward is proposed to provide assistance in the closed-loop control, in order to reduce the disturbances that affect the system. This method is compared with the fuzzy one, which is based on the concepts of artificial intelligence, genetic algorithm, neural networks, and fuzzy logic. For this controller, Gaussian membership functions have been established, a universe of discourse ranging from -6 to 6 for the error and its derivative, and a universe of discourse ranging from -0.5 to 0.5 for the control variables. From the results of this study, it has been concluded that the tracking error in the output temperature under the variation of the set-point decreases in a faster way in the PID with feedforward respect to the classical PID. However, the fuzzy adaptive PID control is based on the optimized parameters.