Using Proportional Integral Derivative and Fuzzy Logic with Optimization for Greenhouse Temperature Control

Abstract

Several Studies were undertaken to evaluate the efficiency of different greenhouse control systems.  Since one of the fastest growing modern technologies in control systems used in greenhouses as well as in other fields is fuzzy logic, further research is needed to study the accuracy of the system compared to PID control system for the same environment and modeling them with the same mathematical model. In this research fuzzy logic controller was tested theoretically and experimentally compared with four PID controllers settings namely, P, PI, PD, and PID in terms of their accuracy and feasibility to control greenhouse temperature.

An optimization procedure was used to determine the best control parameters for PID and Fuzzy Logic controllers. Five tests were conducted to cool the greenhouse using evaporative cooling system during summer season.

Results of the research indicated that PI and PD controllers were the most efficient controllers in the controllers output or ventilation rate behavior with a zero overshoot and small maximum and minimum error from the set point. However, the Fuzzy Logic controller made the closest mean to the set point. No significant difference was noticed between the control behavior of fuzzy logic controller and the PID controllers. Therefore, fuzzy logic controller is considered an equivalent and alternative to PID controller in greenhouse climate control.