Servo motor refers to the engine that controls the operation of mechanical components in a servo system, and is an indirect variable speed device that supplements the motor.

The servo motor can control speed with very accurate position accuracy, and can convert voltage signals into torque and speed to drive the control object. The rotor speed of the servo motor is controlled by input signals and can react quickly. In automatic control systems, it is used as an executing element and has characteristics such as small electromechanical time constant and high linearity. It can convert the received electrical signal into angular displacement or angular velocity output on the motor shaft. It is divided into two categories: DC and AC servo motors, and its main feature is that there is no self rotation phenomenon when the signal voltage is zero, and the speed decreases uniformly with the increase of torque.