Design And Optimization Of A General Aircraft’s Hybrid Electric Propulsion System

The hybrid-electric aircraft combines the advantages of piston-engine aircraft andelectric aircraft. Compared to electric aircraft, the initial cost of hybrid-electric aircraft islower and its endurance is longer. Compared to piston-engine aircraft, on the premise ofoverall performance is not reduced, it is more prone to energy conservation andenvironmental protection. The hybrid-electric propulsion system is a new kind of aircraftpropulsion system which has the bright development and promotion prospects. Compared tothe two types of conventional aircrafts, it adds the kinds and compound modes of propulsionsystems patterns. According to the flight profile, system working mode is optimized, so thatthe main power source-piston engine can work in the area where energy cost and pollutionemission is low. It could be ensured that the aircraft has a good power performance, lowemissions and low energy cost.In this thesis, on the basis of analysis of the key components on the hybrid electricpropulsion system, the reference aircraft (AMT200) of drag polar and basic performancecharacteristics (including: drag, power, range and endurance) are analyzed, and a conceptdesign method of hybrid electric propulsion system is put forward. Furthermore, according tothe output power, the weight of engine and motor are estimated. Determine the performanceparameters such as the weight, power requirements, energy consumption, energy cost andcarbon dioxide emissions of the improved hybrid electric aircraft and compared with thecorresponding parameters of the reference aircraft. In addition, the hybrid electric propulsiontransmission system is designed and simulated. Combined with the characteristics of threekinds of working state: the engine and electric motor work together at the same time, engineworks alone, motor works alone, calculation and parametric design of a planetary gear issuitable for the hybrid system. By using the designing software CATIA, a planet gear systemthat is suitable for hybrid electric propulsion transmission system is calculated andparameterization designed.The results show that although the hybrid electric aircraft is heavier, the running cost andcarbon dioxide emissions of hybrid electric propulsion system greatly reduced. The energyconsumption cost of hybrid electric aircraft accounts for only63%of the original modelreference aircraft (AMT200), and the carbon dioxide emissions also accounts for only45%ofthe original reference aircraft. The research has not only achieved the purpose of lowering fuel consumption and emissions, but also verifies the design rationality of the hybrid electricpropulsion transmission system and the feasibility of the implementation the two hybridelectric propulsion coupling in general aircraft.