Conceptual design of hybrid propulsion system for one seat an aircraft and effects on vehicle performance

With an increasing understanding of the clean environment, the aviation industry has turned to renewable energy sources that provide electrical propulsion. Fuel cells are one of the most popular sources of power for electric vehicles terms of being greener, more reliability and higher efficiency. Among fuel cells, the most attractive option for flight is polymer electrolyte membrane fuel cells (PEMFC). In this thesis, in order to contribute to the concept of electric aircraft in literature, it was aimed to design conceptual hybrid propulsion system by using fuel cell and battery to Cri-Cri which is a single seat aircraft. For the conceptual design, the maximum take-off weight and accordingly the required power was estimated. Then, the characteristics of the aircraft such as take-off speed, take-off distance, climbing rate, climbing speed, climbing angle were determined and the power consumption during the take-off, climbing, cruising and landing stages were determined. Finally, the electrical structure study has been made. The main components of the electrical structure are electric motor, fuel cell system, battery, DC/AC converter and DC/DC converter.After the design was completed, the weight analysis was performed and the duty cycle was determined. Then the amount of hydrogen consumed and the amount of energy consumed were calculated. As a result, Cri-cri needs 26 kW during take-off, 30 kW during climb, 10 kW during cruise and 7 kW during descent. It also consumed 0.68 kg of hydrogen in total, including 0.1 kg in the take-off and climb, 0.52 kg in the cruise and 0.06 in the descent. The remaining 0.32 kg of hydrogen is reserved for use in emergencies. The total amount of energy consumed is 31 kWh.