Sensorless Control of Outer Rotor Brushless DC Motor With Back-EMF Observer for Drone

Abstract

The outer rotor brushless direct current motor, which is a highly speed, efficiently, silence and long-life motor, is the most popular motor for drones. Control methods of this type of motor is the most important parameter to be considered. The hall effect sensors, that used in BLDC motor, are not trustable in control applications therefore the back-EMF observer method can be operated for sensorless control. Reducing the production cost of the drive for drone applications is one of the primary goals of manufacturers. Manufacturing cost reduction is often achieved by eliminating driver auxiliary components such as sensors. The use of these sensors, which are important for the detection of rotor position, has been eliminated with sensorless driver designs. This study presents a sensorless outer rotor BLDC motor driver algorithm with back-EMF observer with motor input terminal current and DC bus voltage independent of rotor speed. The sensorless driver model proposed in the study was implemented for a 330W drone motor with a rated voltage of 14.8V. The proposed sensorless control algorithm is proved by MATLAB/SIMULINK results