Dc brushless motor features

Dc brushless motor has many advantages, but it is worth mentioning that it has fast response, large starting torque, and can provide rated torque from zero speed to rated speed. It controls the current component of DC brushless motor in two axes, and realizes similar motor control and comparable performance with DC motor. However, in terms of characteristics, it is necessary to use complex control technology to achieve the same performance as the brushless DC motor.

In addition, there are more microprocessors to control the motor needs to function inside the chip, and the volume is getting smaller and smaller; Like analog/digital converter, pulse width modulation, etc. Brushless DC motor is an application that electronically controls the commutation of AC motor to obtain the characteristics similar to DC motor and avoid the defects of DC motor mechanism.

There must be an Angle between the rotor field and the stator field. It is not necessary to judge whether the brushless DC motor is in the state after startup, but to execute the next command according to the action state returned from the sensor. The command is to turn three pairs of coils on and off, and these switches are carried out by the transistor. Rotation is achieved by simply charging or discharging the three pairs of transistors in a certain sequence.

Because the zero part of the trapezoid part of the opposite direction of the voltage, so the voltage comparator can detect the voltage positive and negative to judge the motor stator action state.

If the waveform is relatively ideal, a curve of three groups of coil voltages can be obtained by integrating the voltage directly. Thus, the control of brushless DC motor is realized. Decide the starting direction, energize the coil in that direction, rotate the rotor to the starting position in a short time, and energize through the next sequential action to make the motor rotate. In order to improve the use efficiency of brushless DC motor, we need to learn different control and speed regulation according to the use environment, improve the use efficiency of the motor, the control and speed regulation method is applied to the speed regulation.