Primary parameters design method for distributed electric propulsion unmanned aerial vehicle

分布式电推进无人机总体参数设计方法研究

¹ School of Aeronautics, Northwestern Polytechnical University, Xi'an 710072, China
² School of Automation, Northwestern Polytechnical University, Xi'an 710129, China
³ Key Laboratory of Aircraft Electric Propulsion Technology, Ministry of Industry and Information Technology of China, Xi'an 710072, China

Received: 13 June 2020

Abstract

Distributed electric propulsion technology brings new ideas to the design of unmanned aerial vehicle(UAV), such as improving aerodynamic efficiency and propulsive efficiency, and new concept of vertical/short takeoff and landing configurations. However, compared with conventional UAV, the propulsion system of distributed electric propulsion UAV is more complex, which brings difficulties and challenges to the design of distributed electric propulsion UAV. Based on its special aerodynamic/propulsive coupling characteristics, this paper studies the design method and process of primary parameters of distributed electric propulsion UAV. A short takeoff and landing UAV with distributed electric propulsion system is taken as an example for the conceptual design and primary parameter design, and the influence of design parameters on the takeoff mass and endurance is analyzed. Finally, the validity of the established design method is verified by the flight test of the prototype. Results indicate that the distributed electric propulsion system accounts for more than 20% of the takeoff mass; the electric ducted fan efficiency, mass specific power of the motor, mass specific power of the electronic speed controller and the resistivity of power wires are the most significant design parameters that affect the performance of the UAV; with the improvement of technologies, the takeoff mass is expected to be reduced by more than 20%, and the endurance is expected to be increased by more than three times.

摘要

分布式电推进动力技术为无人机的设计带来了新的思路，例如提高气动效率和推进效率以及新概念垂直/短距起降构型等。然而和常规无人机相比，分布式电推进无人机的动力系统更为复杂，这为分布式电推进无人机的设计带来了难度和挑战。研究了考虑气动/推进耦合特性的分布式电推进无人机总体参数设计方法和流程。以一架分布式电推进短距起降无人机为算例进行了概念设计和总体参数设计，并对设计参数对起飞质量和续航性能的影响进行了分析，最后通过原理样机的飞行实验对所建立的设计方法的有效性进行了验证。结果表明，分布式电推进动力系统在起飞质量中的占比超过20%，动力系统中的涵道风扇效率、电机功率系数、电子调速器功率系数和供电线电阻率是影响无人机性能最显著的设计参数，随着技术水平的提升，起飞质量有望降低20%以上，续航性能有望提升3倍以上。