Steam temperature control of hydro-diffusion essential oil extraction system using hybrid-fuzzy plus PID controller

In extracting the essential oils, some of the influential factors need to be considered which can affect the yield and quality of the oils. Many studies have performed on several influential parameters and dictated that the temperature of extraction plays an important parameter that can give large effect on yield and quality. In order to regulate the temperature, a suitable controller is required. However, until now, very little publications stress on the control development of essential oil extraction system. This work proposed the simulation comparative studies on control performance of hybrid fuzzy plus PID controller using 3, 5 and 7 membership functions to regulate the steam temperature of hydro-diffusion essential oil extraction system. The ARX model was used to represent the system dynamic. The effectiveness of the proposed controller was tested via robustness test. Based on the simulated outcomes, the step responses analysis shows that the controllers performed very well. From the set point tracking test, the developed controllers were able to track the changes of set point whether in small or large set point change. There were also true for load disturbance tests.