Electric Propulsion System Optimization Using Performance Maps

초록

This paper presents a performance map based approach that enables the holistic analysis and design of electric propulsion systems composed of an electronic speed control, a motor, a propeller, and an airframe. As all the performance parameters, including the flight speeds and climb rates, are expressed as contours, this approach provides insights into the performance of the combined propulsion system, not only for a single cruise condition, but for a wide range of operating conditions. First, by using the rotational speed and torque as the two independent variables, the process of computing the efficiency and plotting the efficiency contours for each component is presented. Selected practical techniques, which utilize data provided by the manufacturer, and which do not require costly measurements, are introduced. The approach based on the performance map is applied to evaluate eight combinations of the electronic speed control, motor, and propeller for a two-meter wingspan unmanned aircraft. The results suggest that the maximum range can vary by more than 10% depending on the selection of the components. The methodology described in this paper can be applied to design optimization, component selection for existing airframe as well as mission design and optimization of electric powered aircraft.