Motion Control Digital Drives

Digital motor drives come in two different types – Non-regenerative and Regenerative as detailed below.

Non- Regenerative Digital Drives

Non-regenarative drives are the most common type of Digital drive used and control motor speed and torque in a single direction only. This is shown in Quadrant 1 or 3 in the diagram below, in both instances the torque and rotation are in the same direction (pulling).

Regenerative Digital Drives

Also known as Four-Quadrant drives, these drives are capable of controlling the direction of torque as well as speed and direction accomplishing all four quadrants in the diagram. These drives have the ability to drive under break conditions (holding) where the mechanical energy of the motor and load is converted into electrical energy and returned to the power source. In this respect it can be viewed much as a generator.

Regenerative drives are basically two Digital drives integrated and interlocked by control circuitry. One drive is responsible for Quadrants 1 and 3 and the other for 2 and 4.

Non-regenerative drives do not have the braking ability of regenerative drives unless fitted with an additional braking circuit but cannot hold a motor in a fixed position. Non-regenerative drives also lack the ability to reverse a motor without additional circuitry to reverse polarity or switch contacts. However while regenerative drives can achieve breaking and reversal, they are more expensive and complex due to double the amount of circuitry required for its two combined drives.