Servo motor is a kind of engine that controls mechanical and electronic components in servo system, and it is one of the simple and variable speed electronic devices of auxiliary motor. Servo motor can convert voltage signal into torque and exclusive to drive control object. Servo motor rotor speed is controlled by the input signal, and has the characteristics of quick response, which is usually used in the executive components of automatic control system. Servo motor is characterized by no auto-rotation phenomenon when the signal voltage is zero, and the speed will decrease at a constant speed with the increase of torque.
Servo motor can convert the received electrical signal into angular displacement or angular velocity on the motor shaft.
Servo motors could be divided into DC servo motors and AC servo motors.