This paper introduces a temperature control technique for a medical herb dryer system. The technique fixes the drying temperature of the medical herbs at 40℃ even in cases of rapidly changing atmospheric conditions. The control of the dryer temperature is achieved through using on/off controller. The designed dryer contains two systems, which are the thermal and electrical systems. The thermal system is designed to heat the drying air by using solar water collector and electric heater. While, the electrical system which contains a photovoltaic (PV)-WIND hybrid system is used to feed the different electrical loads of the dryer system. The control technique is investigated through simulation work by using MATLAB-SIMULINK. The simulation results indicate the high capability of the proposed technique in controlling the drying temperature, even in case of rapidly changing atmospheric conditions.
Cite this paper
A. Nafeh, E. Sweelem and F. Fahmy, "Temperature Control in a PV-WIND Medical Herb Dryer System," Smart Grid and Renewable Energy, Vol. 4 No. 2, 2013, pp. 153-160. doi: 10.4236/sgre.2013.42019.
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