油电混电技术通过对二次能源系统的优化，不但可以提高能源的利用效率，还具有电推进独有的尺寸独立性优势，可以将多个螺旋桨分布式布局而无显著的效率和重量变化，在通用航空技术发展中具有极大的潜力和优势。基于固旋翼飞行器的顶层设计要求以及初始最大起飞重量的估计值，通过性能约束构造混电系统设计区间，先后得到固定翼模式动力系统和旋翼模式动力系统的初始设计参数，结合具体的飞行任务计算出电池和燃油的重量。经过多次迭代计算，并对每一次迭代获得的推进系统参数进行能量运行检验，最终确定推进系统的设计参数，包括混电系统及其各分系统重量、电池和燃油重量等。此外，在推进系统设计区间内，以功率混合度为调节变量，分析了最小化飞行器最大飞行重量（MTOM）和最小燃油消耗2种优化目标的设计差别，为不同应用场景的混电飞行器设计提供依据。最后通过对比分析，验证了设计方法的有效性。
Through optimization of secondary energy systems, hybrid-electric systems can improve the efficiency of energy utilization, and gain a unique advantage of size independence of electric propulsion, which can distribute multiple propellers without significant changes in efficiency and weight, thereby having great potential in the development of general aviation technology. In this paper, based on the top-level design requirements and an estimated initial Maximum Takeoff Mass (MTOM) of a fixed-wing Vertical Takeoff and Landing (VTOL) aircraft, the design space of the hybrid-electric system is constructed by point performance constraints, through which the initial design parameters of horizontal and vertical propulsion systems are obtained. Combined with the specific mission, the weight of the battery and fuel is calculated. After several iterations and energy operations, the design parameters of the propulsion system are obtained, including the MTOM, the weight of each component of the hybrid-electric system, and the weight of battery and fuel. In the design space, taking the hybridization of power as a variable, we analyze the different design objectives between the minimum MTOM and the minimum fuel consumption, providing the design basis for the hybrid-electric aircraft in different scenarios. Finally, the effectiveness of the design method is verified through comparison analysis.
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