PLC BASED FUZZY LOGIC CONTROLLER FOR A DEFINED TEMPERATURE PROFILE

Abstract

Water baths are used in industrial clinical laboratories, academic facilities, government research laboratories environmental applications as well as food technology and wastewater plants. Because water retains heat so well, using water baths was one of the very first means of incubation. Applications of water bath include clinical laboratory for sulfur test of Petrol and Diesel at different temperature. So we defined a temperature profile for same. In this project, the development of a water bath temperature system to control the liquid’s temperature in the water bath will be presented. In order to develop the water bath temperature control system, MATLAB fuzzy logic toolbox will be utilized. The Fuzzy Logic Controller (FLC) is designed to control water temperature based on the input acquired from the thermal transducer sensor. The 7 x 7 matrix rules for the controller will be used in this project. The output temperature is validated based on the simulation’s temperature profile which is initially set by user. It can be concluded the performance of study with the simulation result. Also a neuro- fuzzy controller (NFC) for temperature control of a water bath system is proposed. A five layer neural network is used to adjust input and output parameters of membership function in a fuzzy logic controller. The hybrid learning algorithm is used for training this network. The simulation results shows that this proposed controller has good set point tracking and disturbance rejection properties. Also it is robust against changes in the system parameters. We also conclude that the proposed adaptive neuro fuzzy controller is better than fuzzy controller.