Comparison of Servo Motor and Brushless Motor

Comparison of  Servo Motor and Brushless Motor

1.Definitions of servo motor and DC brushless motor:

Servo motor is a precise control motor mainly used for applications that require high-precision speed and position control. They are usually equipped with encoder feedback, which can monitor the position and speed of the motor shaft in real time. The control of servo motor usually requires complex algorithms, such as PID controllers, and can be powered by AC or DC, can also called AC motor, DC motor and DC brush motor etc...But most modern servo motors are powered by AC. Its characteristic is that it can accurately control the angle, speed, and position of the motor, which is suitable for scenarios that require high-precision control. Servo motor are widely used in automation production lines, robots, medical devices, aerospace and other fields.

Brushless DC motor combines the control characteristics of DC motors with the brushless structure of AC motor, using electronic commutators instead of mechanical commutators, suitable for high-efficiency and high-speed applications. Compared with traditional brushed motors, it does not require the brush to come into contact with the rotor, and does not generate electric sparks when the speed reaches tens of thousands of revolutions. Therefore, it has the advantages of long service life, strong anti-interference ability, and large braking torque. Brushless motors are widely used in fields such as power tools, toys, photography equipment, electric vehicles, etc., such as fans, pumps, and power tools.

2、 Characteristics of servo motors and brushless motors

The servo motor has high control accuracy, fast speed, and smooth operation. It has strong adaptability and stability, can adapt to different loads and working conditions, and can work stably at high speeds and high torque output states. In addition, servo motors can also achieve stepless speed regulation, adjust output torque and speed as needed, and quickly respond to external loads, control signals, and system feedback. But servo motors are expensive and difficult to install and debug.

Brushless motors have the characteristics of high output torque, low noise, long lifespan, and strong anti-interference ability during use. Brushless motors do not generate electrical sparks, thus ensuring high safety and maintaining efficient operation even under high loads. Brushless motors have a simple structure, small size, light weight, easy installation, and relatively affordable price.

3、 Comparison of torque between servo motor and brushless motor

Under the same conditions, the torque of a servo motor is generally greater than that of a brushless motor. This is because the servo motor adopts a feedback control system, which can adjust the output current and torque, thereby obtaining a larger output torque. The output torque of a brushless motor depends on the rotor and power circuit design of the motor, and its torque value is relatively small.

4、 Differences in Applicable Scenarios

Servo motors are suitable for applications that require high-precision motion control and high-speed, high torque output, such as CNC machine tools, CNC machine tools, packaging machinery, printing machinery, injection molding machinery, etc. Brushless motors are suitable for applications that require high torque output and strong anti-interference capabilities, such as power tools, photography equipment, electric vehicles, etc.

【 Conclusion 】 Servo motor and brushless motor each have their own characteristics and can replace each other in different scenarios. In general, the torque value of servo motors is greater than that of brushless motors, but they are expensive and difficult to install and debug. Brushless motors have relatively small output torque, but they are relatively inexpensive and easy to install. The selection of specific application scenarios needs to be judged based on specific circumstances and requirements.

There are significant differences between servo motors and brushless DC motors (BLDC) in terms of functionality, application scenarios, and control methods. ‌In short, when choosing a suitable motor, it is necessary to comprehensively consider the specific application requirements, performance requirements, cost budget, and maintenance capabilities. Each type of motor has its unique advantages and limitations, suitable for different application scenarios.