Intelligent fuzzy controller for a solar energy wood dry kiln process

This paper presents the design of a hybrid intelligent fuzzy controller which combines optimal fuzzy controller (OFC), fuzzy controller (FC), and adaptive fuzzy controller (AFC). The controller was design algorithmically in which the membership functions were constructed based on the process´ characteristics and the combined controllers´ performance. The control algorithm is implemented in a solar energy wood drying kiln process and was developed using input-output data pairs. The membership functions were design in such a way that the process is stable and robust to variations on environment´s weather and process´ time constant or delay. The developed control system involves the control of temperature and ambient humidity at different operating zones. The model of the process was developed using system identification method based on online input/output data and knowledge that were accumulated through extensive tests. The basis for tuning the membership function is derived from the drying schedule of a specific wood specimen. The developed algorithm was implemented on a microcontroller AVR ATmega 128 using programming language bascom. The implementation results of the developed control algorithm show that the proposed approach for control system design has a great potential to improve the performance of wood dry kiln process.