Conceptual Design of Fuel Cell Based Hybrid Unmanned Air Vehicle

Abstract

Unmanned air vehicles (UAVs) are used successfully in many different fields mainly various military and civilian applications. Recently electric powered UAVs have become more preferable due to their better accessibility, cost, transportation and silence. However, the batteries used in electric UAVs still do not have enough energy density for long endurance flights. Due to the difficulty of using piston and gas turbine engines in small-sized UAVs, hydrogen fuel cells are seen as one of the considerable options to increase endurance and range. In this study, conceptual design of hybrid UAV including fuel cell, solar unit and battery is presented. Small, light and high endurance UAV was designed using aerodynamic calculations and minimum power requirement for cruise flight was determined. 100 W fuel cell produced by Horizon Fuel Cell Technologies and 3S, 5 Ah of battery were used for main power supplies, moreover solar cells to charge the battery were designed to mount on the surface of the wings. Also, a new power management system is designed for switching between the energy sources. As a result of this work, it is determined that fuel cells and solar units are the significant options which can increase the endurance of UAV up to 8 times depending on the design, solar flux, hydrogen capacity etc.