Servomotor

The word servitude comes from the Greek word meaning "slave". "Servo motor" can be understood as the absolute obedience of the control signal command of the motor: before the control signal is issued, the rotor is stationary; When the control signal is issued, the rotor rotates immediately; When the control signal disappears, the rotor can stop immediately.

Servo motor is a micro special motor used as an executive element in the automatic control device. Its function is to convert electrical signals into angular displacement or angular velocity of the rotating shaft. Servo motor, also known as the executive motor, is used as an executive component in the automatic control system to convert the electrical signals received into the angular displacement or angular velocity output on the motor shaft.

Classification of servo motors

Servo motor is divided into AC servo and DC servo two categories.

The basic construction of an AC servo motor is similar to that of an AC induction motor (asynchronous motor). There are two excitation windings Wf and control windings WcoWf on the stator with a phase space displacement of 90° electrical Angle, which are connected to a constant AC voltage. The change of AC voltage or phase applied to Wc is used to control the operation of the motor.

Ac servo motor has the characteristics of stable operation, good controllability, fast response, high sensitivity and strict nonlinearity index of mechanical characteristics and regulation characteristics (less than 10% ~ 15% and less than 15% ~ 25%, respectively).

Advantages and disadvantages of DC servo motor

Advantages: good speed control features, in the whole speed range can achieve smooth control, almost no oscillation, more than 90% of the high efficiency, less heat, high speed control, high accuracy position control accuracy (depending on the encoder), rated operating area, which can realize constant torque, moment of inertia is low, low noise, no brush wear, free maintenance (applicable to clean, explosive environment).

Disadvantages: more complex control, drive parameters need to be adjusted on the spot PID parameters to determine, need more wiring.

Dc servo motor is divided into brush and brushless motor.