Servo Drives / Servo Amplifiers
Servo systems can be used in CNC machining, factory automation, and robotics, amongst other things. Their main advantage over 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. Servos, 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.
All Servo Motors require a Servo drive sometime referred to as a Servo amplifier. This unit converts the command signal into a set amount of current which is then fed to the motor. Current is directly proportional to torque, so the servo is controlled by this variable. The speed / torque curve of the motor is the key factor to consider when specifying a replacement motor, or when speccing a complete system. Our technical department can help in this regard should you require it.
Types of Servo Amplifier
There are two main types of servo amplifiers used, these are Linear Servo Amplifiers and Pulse Width Modulated Amplifiers.
Linear Amplifiers are usually used in applications requiring less than 100 watts, or when the input cannot be switched due to the limitations of other parts of the system. These types of servo amplifier generally run hotter.
PWM Servo Amplifiers switch the voltages on and off at high speed to acheive the avearage target voltage. This results in a more energy efficient servo drive and also creates far less heat. These are far more common than the linear amplifiers mentioned previously.
Servo Drives Features
Most modern Digital Servo Drives include built in communications interfaces. These interfaces allow for full system control over standard fieldbus netwokrs, allowing the operator to fine tune the entire system from one screen. These drives also feature self tuning, with parameters set and stored on the drive which are then used to auto adjust on the fly.
Digital Servo Drives also offer far higher bandwidth than analogue systems, allowing for far better control and much better control of position, velocity and torque.
Need Assistance Working Out Which Drive You Require?
If you need specialist components or just a hand to work out which drive would suit what you need then give us a call on 01905 887 667. Our staff are available during office hours and will be happy to help you with any questions.