How Does a Servo Drive Work? Darwin Motion Professionals Explain

Posted on 7th Dec 2022

A servo drive refers to an electronic device, which is part of a closed loop system. It produces current and voltage to revolve a servo motor. The closed loop system integrates the servo drive, servo motor and feedback device, and gets a commanded in analog or digital signal form.

Servo drive can be often termed as an amplifier that takes the command signal for position, speed or torque requisite and adjusts the servo motor’s applied voltage and or current by using closed loop control.

A servo drive is an essential part of a servo system that even includes the controller, motor and feedback device. Simple digital and analogue i/o or digital fieldbus communication, including EtherCAT, CANopen, and many more industry standard protocols, can be used to communicate to and from controllers and other devices.

Servo Drives are vital part of our product portfolio here at Darwin Motion Pvt. Ltd - VFD, Variable Frequency Drive & Servo Drive Manufacturer. We design and develop broad range of servo drives such as Matrix 180, Matrix 190, Matrix 500, Matrix 680, Matrix 880, and Matrix 500-HF at affordable price.

Servo drives comes in various voltage and current ratings and may offer position, velocity, and/or torque control. Servo motor type broad range are controlled using servo drives that include AC, DC , brushed, brushless, rotary, or linear motors. Potentiometer, resolver, Hall effects, encoder, linear transducer, tachometer, or any other appropriate sensor can be a feedback device. The servo drive has the tendency to powers the motor and make comparison of feedback data along with verifying that the servo motor is operating as commanded or not. PLC, CNC, or motion controller are some of the sources from which command signals are supplied.

When you break down the working of a servo drive, you might know that there are two major elements common in all servo drives which are as follows the power stage and servo loops. The drive power stage starts with input power from an AC or DC source and uses transistors in an H bridge configuration for delivering power to the servo motor. The transistors work like a switch to ease voltage and current flow though the servo motor in any direction, offering forward or reverse motion.

The servo loops offer proportional control of the motor according to the input command signal. A simple servo drive might include a single servo loop for controlling torque. More advanced servo drives have a velocity loop and might include a position loop. In a whole servo drive system, a digital signal offered by a motion controller will command a specific motion profile using all three servo loops tuned for best performance. Each loop signals the following loop and examine the proper feedback elements to make on time corrections for matching the commanded parameters.

Servo drives comes with ASIC chips where an electronic design engineer might incorporate a customized control platform, or as ready for connecting "box” built units.  Also, servo drives come integrated into motion controllers with full I/O and safety elements in one package.

If you want to know your current and voltage requirements for a drive? You can search Darwin Motion product catalogue and identify what best fits your needs.