Analysis of brushless motor structure.

Analysis of brushless motor structure.

Structurally, there are similarities between brushless motors and brushed motors, including rotors and stators, but the structure is opposite to that of brushed motors; The rotor of a brushed motor is a coil winding connected to the power output shaft, and the stator is made of permanent magnet steel; The rotor of a brushless motor is made of permanent magnet steel, which is connected to the output shaft along with the housing. The stator is a winding coil, and the commutation brush used to alternately transform the electromagnetic field in a brushed motor is removed. Therefore, it is called a brushless motor. Now there is a problem, as there is no transformation of the electromagnetic field.

Brushless DC motor consists of a motor body and a driver, and is a typical electromechanical integrated product. Due to the self controlled operation of brushless DC motors, they do not require additional starting windings on the rotor like synchronous motors that start under heavy loads under variable frequency speed regulation, nor do they produce oscillations and loss of step during sudden load changes. The permanent magnets of small and medium-sized brushless DC motors now mostly use high magnetic energy level rare earth neodymium iron boron (Nd-Fe-B) materials. Therefore, the volume of rare earth permanent magnet brushless motors is reduced by one frame size compared to three-phase asynchronous motors of the same capacity.