Performance Assessment of a Distributed Electric Propulsion System for a Medium Altitude Long Endurance Unmanned Aerial Vehicle

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.

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Design of an Electric Propulsion System for a Quadrotor Unmanned Aerial Vehicle

Journal of Aircraft ◽

10.2514/1.38409 ◽

2009 ◽

Vol 46 (3) ◽

pp. 1050-1058 ◽

Cited By ~ 21

Author(s):

Michael J. Stepaniak ◽

Frank van Graas ◽

Maarten Uijt De Haag

Keyword(s):

Unmanned Aerial Vehicle ◽

Electric Propulsion ◽

Propulsion System ◽

Electric Propulsion System ◽

Aerial Vehicle

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Modeling of Solar Electric Propulsion System for UAVs

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.b1040.0782s519 ◽

2019 ◽

Vol 8 (2S5) ◽

pp. 200-202

Keyword(s):

Renewable Energy ◽

Electric Propulsion ◽

Electrical Energy ◽

Propulsion System ◽

Weight Class ◽

Electric Propulsion System ◽

Solar Electric Propulsion ◽

Military Applications ◽

Solar Powered ◽

Long Endurance

UAVs are growing their importance in both civil and military applications. The endurance of UAVs are related to their on board fuel carrying capacity which is limited by the weight class of aircraft. There is a need for long endurance UAVs for persistent Intelligence, Surveillance, Target Acquisition, and Reconnaissance(ISTAR) missions. One of the solutions to overcome the endurance limitations for usage of UAV is the renewable energy. Among all renewable energy, solar energy is found more economical. Electrical powered aircraft/(UAV) propulsion system uses electrical energy to change the velocity of UAV. Electric propulsion system is now mature and widely used technology on spacecraft. In this work, UAV with solar cells on the surface of the wings as well as on board energy storage is discussed. This paper quantifies the requirement for perpetual endurance in solar-powered flight.

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Indirect engine sizing via distributed hybrid-electric unmanned aerial vehicle state-of-charge-based parametrisation criteria

Proceedings of the Institution of Mechanical Engineers Part G Journal of Aerospace Engineering ◽

10.1177/0954410019843722 ◽

2019 ◽

Vol 233 (14) ◽

pp. 5360-5368

Author(s):

S Wang ◽

JT Economou ◽

A Tsourdos

Keyword(s):

Unmanned Aerial Vehicle ◽

Electric Propulsion ◽

Combustion Engine ◽

Electrical Power ◽

Propulsion System ◽

State Of Charge ◽

Electrical System ◽

Starting Conditions ◽

Aerial Vehicle ◽

Hybrid Electric

This paper presents a design process for the challenging problem of sizing the engine pack for a distributed series hybrid-electric propulsion system of unmanned aerial vehicle. Sizing the propulsion system for hybrid-electric unmanned aerial vehicles is a demanding problem because of the two different categories of propulsion (the engine and the motor), and the electrical system characteristics. Furthermore, what adds to the difficulty is that the internal combustion engine does not directly drive the propellers, but it is connected to an electrical generator and therefore provides electrical power to the electric motors and propellers. Hence there is a clear distinction from the traditional engine solutions which are mechanically coupled to the propeller. This paper addresses this specific distinction and proposes an indirect solution based on properties on the electrical part of the system. In particular, a novel parametric characterisation engine sizing approach is presented using the battery pack state-of-charge during a realistic unmanned aerial vehicle flight scenario. Five candidate engine options were considered with different starting conditions for the electrical system. The results show that by using the state-of-charge properties it is possible to select an appropriate size of engine pack while carrying a suitable electrical propulsion pack. However, the solutions are not unique and are appropriate for given design criteria clearly indicated in the paper.

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Performance Assessment of an Integrated Parallel Hybrid-Electric Propulsion System Aircraft

Volume 3: Coal, Biomass, Hydrogen, and Alternative Fuels; Cycle Innovations; Electric Power; Industrial and Cogeneration; Organic Rankine Cycle Power Systems ◽

10.1115/gt2019-91459 ◽

2019 ◽

Author(s):

Smruti Sahoo ◽

Xin Zhao ◽

Konstantinos G. Kyprianidis ◽

Anestis Kalfas

Keyword(s):

Performance Assessment ◽

Electric Propulsion ◽

Electrical Power ◽

Propulsion System ◽

System Level ◽

Electric Propulsion System ◽

The Core ◽

Parallel Hybrid ◽

Overall Efficiency ◽

Hybrid Electric

Abstract Hybrid-electric propulsion system promises avenues for a greener aviation sector. Ground research work was performed in the past for the feasibility assessment, at the system level, for such novel concepts and the results showed were promising. Such designs, however, possess unique challenges from an operational point of view, and for sizing of the sub-system components; necessitating further design space exploration for associating with an optimal operational strategy. In light of the above, the paper aims at presenting an operational analysis and performance assessment study, for a conceptualised parallel hybrid design of an advanced geared turbofan engine, based on 2035 timeframe technology level. It is identified that the hybrid power operation of the engine is constrained with respect to the requirement of maintaining an adequate surge margin for the low pressure side components; however, a core re-optimised engine design with consideration of electrical power add-in for the design condition, relieves such limit. Therefore such a design, makes it suitable for implementation of higher degree of hybridisation. Furthermore, performance assessment is made both at engine and engine-aircraft integrated level for both scenarios of hybrid operation and the benefits are established relative to the baseline engine. The performance at engine level engine specific fuel consumption (SFC), thrust specific power consumption (TSPC), and overall efficiency, shows improvement in both hybridised scenarios. Improvement in SFC is achieved due to supply of the electrical power, whereas, the boost in TSPC, and overall efficiency is attributed to the use of higher efficiency electrical drive system. Furthermore, it is observed that while the hybridised scenario performs better at engine level, the core re-optimised design exhibits a better saving for block fuel/energy consumption, due to the considerable weight savings in the core components.

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