Production of PEM fuel cell-lithium polymer battery hybrid system powered mini-UAV and modelling of energy management system

In recent years, the use of mini-UAVs has become increasingly common. Mini-UAVs which are used in military and civil applications have electric source or internal combustion engine in the drive system as required. Driven by the hybrid system, where electricity is supplied from different sources, the UAVs are intended to remain in the air longer. For this reason, fuel cells and batteries are hybridized and have advantages over systems using only batteries under the appropriate energy management system. In order to make these advantages feasible, battery operated flight tests of the UAV produced within the scope of this study were performed. In addition, the hybrid system with the theoretical power and energy values deemed necessary during the design phase was brought together and the ground tests and thrust tests of the system were performed under laboratory conditions. In the light of the data obtained from the battery flight tests, a hybrid system was operated for a sample flight profile and the change of battery voltage was observed during operation. In the light of the quasi-experimental data obtained, an energy management system for a flight profile was modeled and experimental and model data were compared. It was observed that the data obtained from the model created in MATLAB / Simulink environment can be obtained with the appropriate energy management model for the battery charge rate, hydrogen tank charge rate, fuel cell operating current. Starting from the task description stage of the UAV, a flow diagram for the energy management and modeling of the hybrid system was created. The hybridization rate for an exemplary flight profile is defined and how this ratio is calculated for each flight phase is determined. Keywords: Fuel cell, Hybridization, UAV, Energy management system