Motor system design for large UAV

Sammanfattning: This thesis investigates the viability of creating a fully electrical motorsystem for a large UAV capa-ble of VTOL. As of today only relatively small UAV's use fully electrical motors as their only sourceof propulsion, larger UAV's have to rely on more traditional combustion or jet engines. The reasonfor this is the low energy density of modern batteries compared to petroleum and diesel, even withhigh eciency standards on electric motors, this means that UAV's relying only on electric motorswill have a very short ight time and thus short operational range. To get around this dierentmethods that aircraft use to achieve VTOL ight was investigated as well as dierent methods forextending the ight time. The resulting UAV will combine the design of normal quadrocopters andmodern sailplanes to create a UAV capable of gliding long distances to increase the range. Severaldierent motors where considered for the motor system and out of these the EMRAX 208 waschosen. For the propeller a size of 68 inch was chosen with a pitch of 28 inch, the specic propellerused for the thesis was two Powern f-blades mounted on an apex hub. Several dierent batterieswhere also considered to poever the motors, the chosen battery is the LE 5000 7S. To control themotors a Gen5-S9 ESC whas chosen, one is needed for each motor. Using these components, theweight of the cargo and an estimated weight of the body the total weight of this UAV is estimatedto be approximately 482 kilograms, the calculated operational range is 11.25 kilometers.