Sub 750-watt electric propulsion dynamometer

Abstract

The recent surge in popularity of small electric UAVs under 2kg (4 lbs.) has exposed a need for reliable electric motor performance data. With these UAVs using propulsion systems below 750 W, the systems designed to test bigger motors cannot be used. Moreover, there exists no standard form in which this data can be used for aerospace design. Existing data for the propulsion system components were studied and the parameters necessary to characterize the motor have been identified. A test system has been designed and built to obtain these parameters. The system is capable of testing a motor under 27,000 RPM running at up to 18.5 V and 45 A at a maximum of 750 W. The system's capability to produce repeatable, and reliable data has been proven. A method to use the obtained data in conjunction with other propulsion system data to characterize the full system and to identify an optimal propulsion system for a UAV design has also been devised. Moreover, the limitations and necessary conditions for the tests have been laid out.