The characteristics of brushless motors are all motors with electronic commutation that have external characteristics of DC motors and are collectively referred to as brushless motors. The emergence of brushless motors has broken the strict boundaries between AC and DC speed control systems. In the history of the development of brushless motors, there have been two types of brushless motors with different structures, namely brushless DC motors and AC commutated brushless motors.
The power of the brushless DC motor is finally supplied in a DC manner. According to the method of obtaining DC power, brushless DC motors usually have AC-DC-AC control systems and DC-AC control systems, which are commonly known as square waves.
The AC commutated brushless motor uses a thyristor inverter to directly convert 50Hz AC power into an AC power supply whose frequency changes with the rotor. Its speed regulation characteristics are similar to DC motors. At this time, the input of the motor is a positive wave.
In fact, the AC commutation brushless motor is much more complicated than the brushless DC motor. In the later naming, there are actually differences. The brushless DC motor has always used the original name, and the AC commutation brushless motor is Called permanent magnet synchronous motor. If the inverter is integrated in the motor, the DC input can still be called a DC motor, but a high-power inverter is usually outside the motor, so the AC power is actually supplied to the motor through the inverter. The structure of a brushless DC motor is very similar to that of a permanent magnet synchronous AC motor. The difference is that the input of a brushless DC motor is a square wave, and the input of a permanent magnet synchronous motor is a sine wave. Therefore, the brushless motor has both DC and AC, you can choose according to your needs.