In the BLDC motor, an electronic microsensor senses the position of the rotor - the rotating part of the motor - and controls the current through the windings of the strator, the stationary part of the DC motor. Unlike the strator, the rotor contains only permanent magnets and moves through the magnetic field generated in the strator.
Compared to brushed motors, brushless motors have higher torque per unit power, have higher reliability, and generate less electromagnetic interference. For drones, especially multicopters, high torque is important because balancing the drone is achieved by changing the propeller speed.
Brushless DC motors are used in industrial and household appliances, automobiles, aerospace, consumer products, medical technology and industrial automation.