Investigation of the performance of a brushless direct current motor at high speeds

Brushless DC motors (BLDC) are very advantageous because they require less maintenance, have high efficiency and can reach high speeds. In this study, a light, high-speed and high-thrust BLDC motor for unmanned air vehicles was produced and the necessary electrical analysis was made. In these analyses, the current drawn by the motor was measured without a propeller, using 14×8 and 18×8 three-blade propellers and using 18*10 two-blade propellers. First, the change in the thrust of the motor, depending on the number of revolutions per minute (RPM), was investigated. It has been observed that the thrust of the motor increases in proportion to the increasing number of revolutions. In the continuation of the study, depending on the current drawn, the number of revolutions and the thrust were examined and the performance characteristics of the engine were determined. Here, it is seen that the number of RPM increases rapidly with the increasing current drawn. Likewise, it was observed that the thrust increased rapidly with increasing curren. Finally, the relationship between the RPM and the thrust was investigated and as expected, the thrust increased with increasing of rpm. As a result, the expected features of the manufactured motor were obtained and the tests were completed successfully.