Modeling and Detailed Analysis of Rule Based, Conventional Fuzzy and Type-II Fuzzy Logic Energy Management Systems of Fuel Cell-Battery Hybrid Powered Unmanned Aerial Vehicles

Abstract

The emissions that aircraft discharge into the atmosphere are growing daily as a result of advancements in the aviation sector and an increase in air traffic. For this reason, studies on the use of more electricity in the field of aviation have also increased. Development in battery technologies accelerates the transition to electric systems. Hybrid systems are preferred to increase the system efficiency and to ensure longer lifespan of energy sources. With this motivation, a hybrid Unmanned Aerial Vehicle (UAV) system in which Fuel Cell (FC) is the main power source and Lithium Ion (Li-ion) battery assists FC in sudden power changes is modelled and analyzed in Matlab/Simulink environment. In hybrid systems, Energy Management System (EMS) is needed to control energy resources and increase the efficiency of the UAVs. In this study, three different EMS structures in UAVs, including rule-based Thermostat on/off, classical and Type-II fuzzy logic are analyzed in detail. These EMS methods are modeled and examined for the hybrid UAV system. The unique value of this study is to apply three different EMS methods to a UAV powered by a fuel cell and Li-ion battery. An important contribution has been made to researchers that the preferred EMS method may be different depending on the system to be used and the number of resources. Although Type-II fuzzy logic EMS gives better results, it is more complex and the decision-making time is longer. For this reason, traditional fuzzy logic EMS is more widely used in most applications.