Nowadays, many automation equipment manufacturers have begun to pay attention to brushless DC motors, replacing previous motors with many insurmountable defects such as low efficiency, high noise, and high power consumption, such as AC induction motors, stepper motors, etc. Recently, I have received many inquiries from customers. Brushless DC motors and brushed DC motors will rotate whether they are powered on. In fact, this is not the case. The brushless DC motor must be equipped with a corresponding driver to rotate. This is determined by the structural principle of the brushless DC motor.

The brushless DC motor replaces the mechanical commutator with an electronic commutator. Because of the electronic commutation, the brushless DC motor requires a driver drive circuit. The commutation circuit of the brushless DC motor consists of two parts: drive and control. These two parts are not easy to separate. Especially for low-power circuits, the two parts are often integrated into a single dedicated integrated circuit.

The Hall sensor inside the motor will sense the current position of the motor rotor, and then determine the order of the power transistors in the converter according to the windings of the stator. The magnetic field generated by the current flowing through the motor coil interacts with the magnets of the rotor to make the motor Turn.

Of course, this simple drive can only guarantee the basic rotation function of the brushless DC motor. Brushless DC motors also have other functions such as PWM speed regulation, FG signal output, analog signal speed regulation, external potentiometer speed regulation, open/closed loop control, etc., which require more complex circuits to implement. We integrate multiple functions on a PCB board to achieve control.

Brushless DC motors belong to the category of permanent magnet brushless synchronous motors. Their performance parameters, model, power supply voltage, output power, phase angle, presence or absence, photoelectric switch or self-identification function must be used in conjunction with a brushless DC motor controller. to operate normally.

Brushless DC motors do not have brushes and commutators, so if they want to maintain the direction of rotation, they must have an electronic commutator. The electronic commutator is controlled by the driver. At the same time, the brushless motor controller can also control the start and stop of the motor, forward and reverse rotation, speed adjustment, overvoltage, overcurrent and undervoltage protection. Therefore, a brushless motor controller is necessary. Even if the DC brushless motor is powered directly, it will not work.

The above is the entire content of why brushless DC motors must be equipped with drivers compiled by the editor of Xinda Motor. I hope it will be helpful to everyone! Xinda Motor Co., Ltd. focuses on the global industrial automation field and is committed to high performance. The R&D and production of high-quality brushless DC motors, stepper motors and supporting drive controllers is a leading high-tech enterprise in China providing motion control technology solutions.