How does the servo motor work? What are the characteristics of DC servo motors

With the development of industry, the application of motors has penetrated into various industries, especially servo motors. In recent years, they have developed rapidly and their technology has become better and better. So, what is the working principle of servo motors? What are the characteristics of DC servo motors?

Servo motors can accurately control speed and position accuracy, and can convert voltage signals into torque and speed to drive control objects. The rotor speed of servo motors is controlled by input signals and responds quickly.

Servo motors are used as actuators in automatic control systems and have the characteristics of small electromechanical time constants, high linearity, and high starting voltage. They are converted into angular displacement or angular velocity outputs on the motor shaft. Divided into two categories: DC and AC servo motors, their main feature is that they do not rotate when the signal voltage is zero, and the speed decreases uniformly with the increase of torque.
Put it simply! Servo motors mainly rely on pulses for positioning, which can be understood as when the servo motor receives one pulse, it will rotate the angle corresponding to one pulse to achieve displacement.

DC servo motors are divided into brushed motors and brushless motors, and there are still differences between the two.

1. Brushed motors have low cost, simple structure, large starting torque, wide speed range, and easy control. However, they are difficult to maintain and can also generate certain electromagnetic interference, requiring high environmental requirements. Can be used for ordinary industrial and civilian occasions with low requirements.

2. Brushless motors have small size, light weight, large output, fast response, high speed, low inertia, smooth rotation, and stable torque. But the control is slightly more complex and easy to achieve intelligence. Its electronic commutation method is relatively flexible, which can be square wave commutation or sine wave commutation. Brushless motors are maintenance free, efficient, operate at low temperatures, emit low electromagnetic radiation, have a long lifespan, and can be used in various environments.