Thermal management of an unloaded hybrid dryer by generalized predictive control

Abstract

The temperature control inside a hybrid dryer has always remained the main concern in drying applications. At present, the majority of the drying community researchers use classical controllers to command the thermal environment inside the drying chamber. Such a control strategy leads to diminish the dryer efficiency and alters the quality of the dried products. In this regard, the objective of this work is to develop an advanced temperature control system for the thermal management of a hybrid solar-electrical dryer. In addition, the proposed system must be convenient, efficient, and affordable in developing countries. A Generalized Predictive Controller (GPC) is designed and validated for temperature control covering a wide range of 40 °C–75 °C. Mathematical and identified models are developed to represent the thermal behavior of the dryer. The identified linear model is used to design the GPC controller. This controller has proven great feasibility and effectiveness by maintaining the chamber temperature with a settling time that remained under 22 min, with a static error of 0.5 °C and no overshoot or dips. Moreover, the GPC algorithm is implemented with an Arduino board which represents an easy, and low-cost solution for temperature control in drying applications.