Battery management system architectures for unmanned air vehicles: a strategic issue

Abstract

Among all of the industrial emissions 3% is produced by aviation. Electric propulsion is a promising option in achieving targets of better environment and sustainability. New concepts of power systems for more electric aircraft (MEA) are being developed, which requires developing demanding battery technologies and other types of energy storage systems. In this roadmap, batteries are strategically critical systems for developing further electric propulsion in aviation. This development also provides benefit to unmanned air vehicles. Using electric propulsion creates more flexible design possibilities for UAVs. Advances in power electronics technologies provide more possibilities for electric power use in UVAs, which also making it possible to use battery technologies. Lithium-ion batteries compared to other electric energy storage systems, provides higher specific energy and energy density. Besides these batteries require to be managed for safe and economic operation. The management function is performed by electronic circuits and systems called battery management systems (BMS). For aviation applications, BMS functions are critical because of the higher safety requirements. Some of the functions can be listed as balancing, over charge/discharge protection, short and overload protection. These functions are related to BMS subsystems which are designed through alternative design architectures. For each specific application, BMS design shall be revisited and BMS subsystems shall be decided according to application specific requirements. While the main focus is safety of the battery or electric energy storage system, reliability is also important for aviation. In this paper, requirements are reviewed for aviation batteries and architecture alternatives and aspects related to BMS design are discussed. It is concluded that, requirement based parametric design of the BMS is essential in aviation battery management applications.