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Fuel cells have been under considerable interest for both commercial and military aviation applications for power generation needed for advanced computational and communication systems on board aircraft, as well as for other power requirements needed both while in flight and on the ground. However, in order to power the fuel cells, hydrogen must be generated at some point, the ideal source being the logistic fuels such as JP-5 or JP-8 that is already used for propulsion. This process is not trivial, as several potential issues can arise from processing logistic fuel, the two primary concerns being the effect of sulfur within the fuel on the processing and fuel cell components, and the longevity issues resulting from coke formation during fuel processing. In the first part of this paper, we look as work that we have performed that addresses some of these issues for the steam reforming of JP-5 to produce pure hydrogen for fuel cell use.

Two high voltage, Series Connected Boost Regulators (SCBR) were developed to demonstrate the benefits of the SCBR topology for low Earth orbit communication satellites. The resulting breadboards had a power density of 1,200 W/kg and a measured efficiency of 95-99%. Several peak power tracking methods and algorithms were implemented to demonstrate the ability of the SCBR to peak power track a solar array. The peak power tracker derived maximum power at all times and reduced the number of sunlight battery discharges necessary. The breadboards also demonstrated several modularity techniques, which will allow a common SCBR module to be used in several applications. The breadboards were tested in an end-to-end high voltage test facility using high fidelity solar array simulators, an actual NiH2 battery, and simulated constant power loads. Design details and test results are presented.