Advantages of brushless DC motors 2
The DC motor has fast response, large starting torque, and can provide rated torque from zero speed to rated speed. The performance of the torque, the armature magnetic field and the rotor magnetic field must be maintained at 90°, which requires carbon brushes and commutators. Carbon brushes and commutators will generate sparks and carbon powder when the motor rotates, so in addition to causing damage to the components, the application is also limited. The AC motor has no carbon brushes and commutators, and is maintenance-free, sturdy, and widely used. However, in order to achieve the performance equivalent to the DC motor, complex control technology can be used to achieve it. With the rapid development of semiconductors today, the switching frequency of power components is much faster, which improves the performance of the drive motor. The speed of the microprocessor is also getting faster and faster, and the control of the AC motor can be placed in a rotating two-axis orthogonal coordinate system, and the current components of the AC motor in the two axes can be properly controlled, which is similar to the control of the DC motor and has the equivalent of the DC motor. performance.
In addition, many microprocessors have implemented the functions necessary to control the motor in the chip, and the volume is getting smaller and smaller; such as analog-to-digital converter (analog-to-digital converter, adc), pulse width modulation (pulse wide modulator, pwm)...etc. The brushless DC motor is an application that electronically controls the commutation of the AC motor to obtain similar characteristics of the DC motor without the lack of the DC motor mechanism.