8/8/2019 What Are the Difference Between Induction Motor and Servo Motor

1/1

What are the difference between Induction motor and servo motor?1. Servo motors is used to control speed systems. It varies the field current

applied to the generator which in turn controls the speed of the motorconnected. Induction motor will work on synchronous speed.

2. Servo motor-closed loop system where as induction motor is an open loopsystem.

3. An induction motor has high inertia and servo motor has a very low inertia.Hence servo motors are used in applications where instant and accurate

positioning of load is reqd.

4.Speed is constant in servo motor.

5.As in induction motor stator is formed by coils while in servo motor stator is

formed with permanent magnet. So in induction motor very high inertia isthere while in servo inertia is low. Due to that servo is very easy to stop at

instant. So it is used in position control while in application where at instantposition stop is not required induction motor is used.

6.The motors are selected according to the torque requirement and based on

the application, for normal industrial application Induction motors areeconomical. For some application which requires high torque, positioningand breaking control, we can use servo motor. Servo needs and drive

package and requires lengthy program.

7.Servo motor is actual normal ac induction motor with added feature as

1) Low inertia rotor 2) high torque break and 3) inbuilt encoder for speedand position feedback. All this components combine work with servo

drive.8.Induction motor has a high inertia whereas servo motor has a low inertia due

to we stop it at any instant. Servo motor has a high starting torque and has acapability to break that torque at any instant, whereas induction motor have a

low starting torque and we cannot stop it any exact position due to high

inertia. Accuracy of servo motor is more than induction motor but it isexpensive. Generally servo motor is to be use where we required a highstarting torque with small displacement. If the servo motor connect with

Servo drive then we needs a 24 volt dc supply to execute or drive.

9.The Only Difference between servo motor and Induction motor is that servo

motor and drive makes a fully closed loop because of built in encoder with

servo motor, but we can make a closed loop system with induction motor byputting an external encoder still there is one addition with servo motor is that

servo motor have permanent magnets which gives better accuracy than

simple induction motor10.

Servo motor has two rotations which are not possible in Induction motor.