The Difference Between Brushed Motor And Brushless Motor

A brushed motor is a rotating motor that contains a brush device, which converts electrical energy into mechanical energy into electrical energy. A brushed motor is the basis of all motors. It has the advantages of fast starting, timely braking, large-scale speed regulation and stable control circuit. Simple and so on. The commutation of the brushed DC motor is always realized by the contact between the graphite brush and the annular commutator on the rotor, while the brushless DC motor feeds back the rotor position to the control circuit through the Hall sensor, so that it knows the commutation of the motor. accurate time. A brushless DC motor consists of a motor body and a driver, and is a typical mechatronic product. Because the brushless DC motor operates in a self-controlled manner, it will not add a starting winding to the rotor like a synchronous motor with heavy-load starting under variable frequency speed regulation, nor will it cause oscillation and loss of step when the load changes suddenly. The permanent magnets of small and medium-capacity brushless DC motors are now mostly made of rare-earth neodymium-iron-boron (Nd-Fe-B) materials with high magnetic energy levels. Therefore, the volume of the rare earth permanent magnet brushless motor is one frame size smaller than that of the three-phase asynchronous motor of the same capacity. What are the specific differences between them?

1. The nature is different: the speed regulation process of the brushed motor is to adjust the voltage of the motor power supply. The adjusted voltage and current are converted by the commutator and the brush to change the strength of the magnetic field generated by the electrode to achieve the purpose of changing the speed. The brushless motor speed regulation process is that the voltage of the motor's power supply remains unchanged, and the control signal of the ESC is changed. , and then change the switching rate of the high-power MOS tube through the microprocessor to realize the change of the speed.

2. Different performance: brushed motor has simple structure, long development time and mature technology. The brushless motor has removed the brush, and the most direct change is that there is no electric spark generated when the brushed motor is running, which greatly reduces the interference of the electric spark to the remote control radio equipment.

3. Different use times: brushless motors have less brushes, and the wear of brushless motors is mainly on the bearings. From a mechanical point of view, brushless motors are almost maintenance-free motors, and only need to do some dust removal when necessary. Maintenance can be done. Brushed motors last longer.