Detailed analysis of energy management systems of hybrid energy source unmanned aerial vehicle

Technological developments in the aviation sector and the number of flights and routes in air traffic are increasing every day. However, the emission amounts of air vehicles at a unit distance are quite high compared to other public transportation vehicles. The European Union Commission aims to reduce carbon emissions by 50% for the year 2030 and to zero carbon emissions for the year 2050. For this reason, the number of studies aimed at using more electricity in the aviation field is also increasing. In addition, advances in battery technologies are also accelerating the transition to electrical systems. Hybrid systems are preferred to increase system efficiency and ensure a longer life of energy resources. With this motivation, a hybrid Unmanned Aerial Vehicle (UAV) system consisting of a fuel cell as the main power source and a Lithium-ion (Li-ion) battery that assists the fuel cell in sudden power changes was modeled in the MATLAB/Simulink environment in this thesis study. In hybrid systems, an Energy Management System (EMS) is needed to control energy sources and increase the efficiency of UAVs. In this study, three different EMS structures, rule-based Thermostat On/Off, Type-Ⅰ and Type-II fuzzy logic, have been analyzed in detail in UAVs. The contribution of this thesis study to the literature is that it is analyzed by applying three different EMS methods to a UAV powered by a fuel cell and a Li-ion battery. The preferred EMS method may also differ depending on the system to be used and the number of resources. Since two sources cannot be used at the same time in the Thermostat On/Off Control Strategy, the efficiency of the system is lower. Although the simulation results of Type-II fuzzy logic based EMS are better, they are structurally more complex and the decision-making time is longer. For this reason, it has been concluded that Type-Ⅰ fuzzy logic EMS can be used more effectively and widely in most applications.