What are the difference between Induction motor and servo motor?

感应电机和伺服电机的区别

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 motor connected. Induction

motor will work on synchronous speed.

伺服电机用在速度控制系统中，它通过变化电场电流来控制电机的速度。感应电机工作的同步速度。

2) Servo motor is closed loop system where as induction motor is an open loop

system.

伺服电机是闭环系统，感应电机是开环系统。

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 required.

感应电机高惯量 伺服电机低惯量，因此伺服电机用在负载需要精确的位置控制的场合。

4) Speed is constant in servo motor.

伺服电机的速度是常量 (这一点不正确)

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 is there

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 instant position stop is not

required induction motor is used.

感应电机的定子是由线圈构成，伺服电机的定子由永磁铁构成(这也不正确)

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

application, for normal industrial application Induction motors are economical. For

some application which requires high torque, positioning and breaking control, we

can use servo motor. Servo needs and drive package and requires lengthy program.