Papers by Author: A.S. Kadalla

Abstract: The main hindrance to the widespread of solar systems is the cost of the solar collectors. Researchers all over the world have been exploring different means of overcoming this limitation in order to make solar conversion more cost effective. This paper describes an experimental work on optimum seeking position of solar collectors using feedback control theory. Single axis tracking mode is employed together with sun seek sensor for automatic reset. The performance of the tracking collector compares favorably against a fixed collector.

Abstract: The problem of precise control of the air – gap of magnetic levitation vehicles is considered in this paper. A sliding mode controller is designed for the levitation control task. Robustness of the controller was investigated using computer simulations. The results show that the controller is robust to parameter variations of up to ±13% and can tolerate disturbances up to ±400N/Kg.