Benefits of Servo Systems
The main advantage of a Servo System compared to traditional DC or AC motors is the addition of motor feedback. This feedback can be used to detect unwanted motion, or to ensure the accuracy of the commanded motion. The feedback is generally provided by an encoder of some sort. Servo Motors, in constant speed changing use, have a better life cycle than typical AC wound motors. Servo Motors can also act as a brake by shunting off generated electricity from the motor itself.
Closed loop systems using Servo Drives offer more reliability and precision in motion applications than open loop systems by using the feedback to account for errors and system disturbances (unlike open loop systems). When compared to straight power amplifiers, Servo Drives offer a wide range of advantages for automatic machining systems, including superior positioning, speed, and motion control.
The Servo Drive is thus responsible for regulating the difference between actual motor status with requested motor status by making the necessary current or voltage adjustments. This differs from an open loop system where the motor could spin at the wrong RPM regardless. Servo Drives enable the motor to respond with damping, feedback gain, and stiffness based on the requirements of the system.
For automatic systems that require position control, this makes the use of a Servo Drive ideal. Whether it is just positioning a globe valve to the right position or aiming a telescope, a Servo Drive can regulate a shaft to its desired position regardless of friction or other disturbances.
So, whether you are looking for a system with greater torque than a stepper motor or just more precise control, a Servo System is most likely a necessary component of your machining or manufacturing process. A broad range of Servo Systems (power output and features) are typically available to offer a solution with the precision and performance required for your automation needs.
For more information regarding Servo Systems, please refer to the following related blog posts:
Tom Jackson
A very comprehensive introduction to the advantages of servo drives. Very nice article