HYBRID POWER SOURCE FOR PSEUDO-SATELLITES.

This paper presents some studies concerning hybrid power sources fuel cell, new generation photovoltaic cells with high efficiency and small battery based for High Altitude Pseudo-Satellites (HAPS). HAPS are recent entrants UAS-s in both directions of research of major aviation companies. Their goal is to replace services provided by classical communications and surveillance satellites, which show a high cost, with services provided by much cheaper technology platforms. It is exposed a state-of-the-art in the field of hybrid power sources used on high altitude UAVs and the future trends in the electrical propulsion of aircraft are highlighted. The hybrid power source's primary energy sources are photovoltaic panels and fuel cells. Regarding the problems that arise in the use of fuel cells on board the HAPS are: power / weight ratio; the energy system design according to the size of aircraft considering the use of fuel cell with solar cells; the need to use a regenerative system that allows to achieve flight durations of the order of five years without returning to the ground. An estimation concerning the possibility to obtain a practically unlimited flight duration using photovoltaic cells and regenerative fuel cells is also presented. [ABSTRACT FROM AUTHOR]