AC Servo Motor

Synchronous AC servo motors
Synchronous AC servo motors are characterized by their ability to operate at a constant speed, which is synchronized with the frequency of the supply current.

The rotor contains permanent magnets or a wound field that interacts with the rotating magnetic field produced by the stator windings, resulting in smooth and precise rotational motion.

Asynchronous (induction) AC servo motors
Asynchronous or induction AC servo motor operates based on the principle of electromagnetic induction, where the rotor is not magnetically synchronized with the stator’s rotating magnetic field.

The rotor lagging behind the stator’s magnetic field creates the torque necessary for rotation. The slip between the rotor and the stator field is what differentiates it from synchronous motors.

Single-phase AC servo motors
Single-phase AC servo motors operate on a single-phase alternating current (AC) supply. They use a stator and a rotor to generate a rotating magnetic field, which induces motion in the rotor.

The stator is equipped with windings that create a magnetic field when AC voltage is applied. The rotor, typically a squirrel-cage type, rotates due to the interaction with the magnetic field, resulting in precise movement.

Two-phase AC servo motors
Two-phase AC servo motors operate on a two-phase AC supply. They use two stator windings positioned at 90 degrees to each other to produce a rotating magnetic field, providing better control and efficiency.

The interaction between the magnetic fields generated by the two stator windings and the rotor creates precise rotational motion. This setup allows for more accurate control of speed and position.

Positional rotation AC servo motor
Positional rotation AC servo motors are designed to move to a specific angle or position based on control signals. They use a stator and a rotor system where the stator creates a magnetic field, and the rotor moves to align with this field, achieving precise positioning.

The stator is equipped with windings that generate a magnetic field when AC voltage is applied. The rotor, often coupled with positional feedback mechanisms like encoders, adjusts its position in response to control signals, ensuring accurate movement.

Continuous rotation AC servo motor
Continuous rotation AC servo motors are designed for continuous 360-degree rotation. They control speed and direction based on input signals, making them suitable for applications requiring constant motion.

The stator creates a rotating magnetic field when AC voltage is applied, and the rotor, usually of the squirrel-cage type, rotates continuously due to this interaction. Speed and direction are controlled via feedback mechanisms such as tachometers or encoders.

Linear servo motor
A linear servo motor converts electrical energy into linear motion rather than rotational motion. They use a stator and mover system where the stator generates a magnetic field, and the mover travels linearly along this field, resulting in precise linear movements.

The stator is equipped with windings that produce a magnetic field when AC voltage is applied. The mover, often equipped with linear encoders, moves precisely in response to control signals, ensuring accurate linear positioning.