AC Servo Drives

Mechanisms belonging to the range of motion electronic products, AC servo drives operate on alternate voltage patterns. As electronic amplifiers, they serve to power electric servo motors that similarly operate on alternate voltage pattern.

As special electronic amplifiers they A) monitor control feedback signals received from motors. B) According to feedback signals received they make necessary adjustments. C) They form a part of a dynamical system.

The function of AC servo drives is guided by the ‘control theory’, which is a sub part of Physics and Mathematics. According to this theory, A) A controller, manipulates the input to a system. B) This manipulation is geared to achieving the desired effect on the output. C) Output variables follow a reference of time. A.C servo drives act as controllers or A.C electrical amplifiers.


"Motion theory" also controls the functioning of servo drives. As special electronic mechanisms, they control the velocity of mechanisms. After receiving a command signal from a control system geared to A.C voltage, they amplify such signals and after due amplification, they transmit electric current to a system. Automatically, the electric current transmitted will be proportionate to the received command signal.

The servo motor with an attached velocity sensor does the needful work of reporting the motor’s actual velocity back to servo drive. After a due comparison of motor’s actual velocity with the command velocity, AC servo drives contribute to altering the due voltage frequency. Thus any error in voltage frequency is corrected by A.C servo drives. Usually servo motors rotate at a velocity matching the control signal. Servo motor control ensures the due matching leading to the establishment with proper configuration and tuning- which is a combination of proportional and derivative gain.

A.C servo drives are not only easily available, but they are also compatible with different variety of motors. Use of A.C servo drives has manifold advantages. Forming an integral part of the servo system their additional feedback serves to detect unwanted motion. They usually accurately assess the commanded motion. Moreover they are better adjusted to changing speed, with a better life span; giving effective durability to a system.

Servo drives are generally of two types. 1) Digital servo deals with discreet tracking of signals. 2) Analog deals with continuous tracking of signals.  Servo drives which form an integral part of the servo system have an enormous role to play in industries involved with robotics, automation and any other kind reliant on motion theory.

Custom Servo drives - an Overview

Custom servo drives are a kind of cost effective and optimized servo drive which are designed according to the customers applications to meet their needs of form, cost, fit and function specifications. Mostly known as the “special electronic amplifiers”, a custom or standard servo drive is commonly used to control the motors of the electric servo.

Over the decades, the technology of servo controls has changed a lot with its size, rotational speed, and torque. Custom servo drives are one of the major developments in the world of servo drives. The custom servo is almost similar to its digital counterparts. They have the same gears, motors and cases and most importantly they have a “Feedback potentiometer or Pot” like the digitals.

Designs of the custom servo drives:

• Optimized packaging- form factors, special connectors
• Multi Axis- two and three axis packages and systems based on racks
• Power Ratings-voltage and custom current ratings
• Java Beans-“fill in the blanks” standard indexer functions
• Enhanced Firmware-standard compensation filters
• Performance Edge-temperature compensation, low noise
• Feedback-special encoders

Classification of custom servo drives:

Custom servo drives can be classified based on the shapes, electric circuitry, sizes, type of feedback, input power variations, command and performance signal. Every factor has a great value in making the decision of the actual price of the custom servo drive.

Usage of custom servo drives:

Nowadays, custom servo drives are usually used in various industries like packaging, robotics, textile, factories of CNC machining and printing. With the increasing usage, the need of custom servo controls has increased a lot.

Advantages of using custom servo drives:

• Power saving ability:  In a custom servo drive, no power is sent to the servo motor when the car is idle. When the signal of moving the car is received, the power is sent to the servo motor up to a maximum voltage and then the servo responses. The servo doesn’t responses until the power reaches the maximum. This helps to save the excess power from being wasted. 
• Immense Standing Torque: The quotients of the standing torques of the custom servo drives are very high.
•  Monitoring: The custom servo drive is able to monitor the feedback signals from the motors by making some subsequent adjustments.

It is a fact that custom servo drives are very essential for the industry which totally depends on the motion control. So, to grow your industry, switch on to custom servo drives.