Referred to using terms such as AC servo drive, amplifier, brushless servo drive, DC servo drive, invertor, power amplifier, PWM DC servo drive, stepper drive, stepping motor controller, speed /position / torque controller, the drive electronics are the power unit in the drive or control system.
They convert the demand signals from the controller and provide controlled power delivery to the electric motor, causing motion.
Taking into consideration factors such as speed, accuracy, size, dynamics, environment etc will determine what technology is best suited to your requirement.
Our product offering focuses on servo and stepper drives, but we also offer solutions for inverter applications.
The definition ‘digital servo drive’ typically describes a drive unit that can be ‘digitally’ configured. The drive does not have potentiometers, resistors, capacitors, solder bridges, etc to effect the set-up, but a programmable interface.
The demand signal, most commonly represents a desired velocity, but can also represent a torque or position.
A feedback sensor in the servo motor reports the motor’s actual velocity and position back to the servo drive (closed loop control).
The term ‘analogue servo’ generally refers to drives (or amplifiers) that operate using an ‘analogue’ control circuit. The control input is typically +/- 10V signal (for speed or torque) or a PWM interface and are available for brushed and brushless servo motors.
Analogue drives are still widely used on medical and metrology equipment, particularly in low-voltage applications.
Stepper systems are typically open-loop. The motor position is controlled precisely without any feedback mechanism. The control is typically via STEP and DIRECTION signals and stepper systems can offer very good speed and position control, especially for low speed applications.