Research On Double-input Cuk Type Full-bridge Converter

As the proposing of the concept that high altitude long endurance unmanned aerial vehicle，solar uavswhich can obtain solar energy while flying are widely noted. A variety of solar uavs are designed byresearchers of various countries. However，solar energy is not stable as weather change quickly，so asupplementary power source is required. Fuel cell is one of ideal candidates for its features of high powerdensity and pollution free. In traditional new energy powering system, every new power source needs aconverter linked. If a multi-inputs converter substitutes for multiple single-input converts, the size andweight can be clearly reduced. This dissertation is researching on this multi-inputs converted for solar cellsand fuel cells.This dissertation obtained a double-input Cuk full-bridge converter which is deduced from thegenerating rules of single-primary-winding multi-input Converter. This converter, compared to thetraditional multi-winding multi-input converters, has a simpler structure and less components. Nevertheless,it can power the load simultaneously or individually. As the input current is continuous, it can be applied tosuch sources like fuel cells, batteries and photovoltaic cells. In addition, an improved control strategy isemployed so that the latter converter can achieve soft switching. Aiming to solve the problem of unstablesolar energy powering， power management is also researched in this dissertation.Finally，the parameters of main circuit、driver circuit and control circuit are designed according toperformance requirements. A1kW prototype of double-inputs Cuk full-bridge converter is developed andtested. Simulation and experiment results proved that the analysis is correct.