Features and advantages of brushless motors

The brushless motor is composed of a motor body and a driver, and is a typical mechatronic product.

    Brushless motor refers to the motor without brush and commutator (or slip ring), also known as the motor without commutator. As early as when the motor was born in the last century, the practical motor produced was a brushless form, that is, an AC squirrel cage asynchronous motor. This motor has been widely used. However, asynchronous motors have many insurmountable shortcomings, resulting in slow motor technology development. The transistor was born in the middle of this century, so a brushless DC motor that uses a transistor commutation circuit instead of brushes and commutators came into being. This new type of brushless motor is called an electronically commutated DC motor, which overcomes the defects of the first generation of brushless motors.

    Features of brushless motors

    1. It can replace DC motor speed control, inverter + frequency conversion motor speed control, asynchronous motor + reducer speed control;

    2. It has the advantages of the traditional DC motor, while eliminating the carbon brush and slip ring structure;

    3. With brake and double steering function;

    4. Small size, light weight, and large output;

    5. Excellent torque characteristics, good middle and low speed torque performance, large starting torque and small starting current;

    6. Stepless speed regulation, wide speed regulation range and strong overload capacity;

    7. Soft start and stop, good braking characteristics, can save the original mechanical braking or electromagnetic braking device;

    8. High efficiency, the motor itself has no excitation loss and carbon brush loss, eliminating multi-stage deceleration loss, and the comprehensive power saving rate can reach 20%~60%.

    9. High reliability, good stability, strong adaptability, simple repair and maintenance;

    10. Resistance to turbulence and vibration, low noise, low vibration, smooth operation and long life;

    11. No sparks, especially suitable for explosive places, with explosion-proof type;

    12. Trapezoidal wave magnetic field motor and sine wave magnetic field motor can be selected as required.

    Advantages of brushless motors

    Different from the brushed DC motor, the brushless DC motor does not use a mechanical brush device, uses a square wave self-control permanent magnet synchronous motor, replaces the carbon brush commutator with a Hall sensor, and uses neodymium iron boron as the permanent magnet material of the rotor , Compared with the general traditional DC motor, it has great advantages in performance, and it is the most ideal speed-regulating motor today. Its advantages:

    High efficiency, low energy consumption, low noise, long life, high reliability, servo control, stepless variable frequency speed regulation, relatively low cost and easy to use.

    The stator windings of brushless DC motors are mostly made into three-phase symmetrical star connection, which is very similar to three-phase asynchronous motors. Magnetized permanent magnets are glued to the rotor of the motor. In order to detect the polarity of the motor rotor, a position sensor is installed in the motor. The driver is composed of power electronic devices and integrated circuits. Its function is to receive the start, stop, and brake signals of the motor to control the start, stop and brake of the motor; receive position sensor signals and forward and reverse signals to control the reverse The on and off of each power tube of the variable bridge produces continuous torque; accepts speed commands and speed feedback signals to control and adjust the speed; provide protection and display, etc.

    Brushless DC motors are widely used in household appliances, auto parts, power tools, office automation, industrial and commercial equipment, medical equipment, personal care, robotics and many other industries.