AC Motor-Based Drive System Functions Without Gearboxes or Pulse Encoders

Standard induction motors, normally designed to run at base speeds between 850 to 3500 rpm, are not particularly well suited for low-speed operation, as their efficiency drops with the reduction in speed. They may also be unable to deliver sufficient smooth torque at low speeds. Use of a gearbox is the traditional mechanical solution for this challenge. However, the gearbox is a complicated piece of machinery that takes up space, reduces efficiency, and needs both maintenance and significant quantities of oil. Elimination of the gearbox via these new permanent magnet motors/drive configurations saves space and installation costs, energy and maintenance, and provides more flexibility in production line and facility design.