Modelling and Experimental Validation of a Hybrid Electric Propulsion System for Light Aircraft and Unmanned Aerial Vehicles

Massimo Cardone,Enrico Fornaro,Bonaventura Gargiulo

doi:10.3390/en14133969

Abstract

This article presents a numerical model of an aeronautical hybrid electric propulsion system (HEPS) based on an energy method. This model is designed for HEPS with a total power of 100 kW in a parallel configuration intended for ultralight aircraft and unmanned aerial vehicles (UAV). The model involves the interaction between the internal combustion engine (ICE), the electric motor (EM), the lithium battery and the aircraft propeller. This paper also describes an experimental setup that can reproduce some flight phases, or entire missions, for the reference aircraft class. The experimental data, obtained by reproducing two different take-offs, were used for model validation. The model can also simulate anomalous operating conditions. Therefore, the tests chosen for the model validation are characterized by the EM flux weakening (“de-fluxing”). This model is particularly suitable for preliminary stages of design when it is necessary to characterize the hybrid system architecture. Moreover, this model helps with the choice of the main components (e.g., ICE, EM, and transmission gear ratio). The results of the investigation conducted for different battery voltages and EM transmission ratios are shown for the same mission. Despite the highly simplified model, the average margin of error between the experimental and simulated results was generally under 5%.

Highlights

Air travel is continuing to experience the fastest growth among all modes of transportation, environmental issues such as noise, emissions, and fuel consumption are becoming important for energy and environmental sustainability [1].High concentrations of air pollutants (e.g., PM2.5, black carbon, CO, NOx) are observed around general aviation airports, with potential health implications for persons living nearby [2]
Glassock et al [6] showed that a short-duration mission such as skydiving equipped with a hybrid propulsion system can contribute to fuel reduction
The one chosen for this application was the parallel configuration, which allows the summing of the power of the internal combustion engine (ICE) and wasEM

Summary

Introduction

Air travel is continuing to experience the fastest growth among all modes of transportation, environmental issues such as noise, emissions, and fuel consumption are becoming important for energy and environmental sustainability [1].High concentrations of air pollutants (e.g., PM2.5, black carbon, CO, NOx) are observed around general aviation airports, with potential health implications for persons living nearby [2]. Much research in the aeronautical field aims to support natural resources by saving emissions; of all the systems, the full electric propulsion system (FEPS) and the hybrid electric propulsion system (HEPS) [4] seem to have a primary role in the sustainable development of general aviation, and for ultralight aircraft, and UAV [5]. These propulsion systems ensure a reduction in noise and exhaust gas emissions, but due to their internal combustion engines, they offer greater mission flexibility with a potential increase in overall efficiency [6,7].

Methods

Results

Discussion

Conclusion