Design and performance of the field regulated reluctance machine

A topological configuration for rotating electromagnetic machines that can produce significantly higher force density than an induction machine is investigated. The stator is constructed using full pitch concentrated windings embedded in conventional slots. Rotor saliency is produced using poles constructed of axially oriented laminations. Operation is such that all of the conductors are actively taking part in torque production all of the time. The means for exciting the stator windings allow for independent control of torque and regulation of the rotor flux. A force density comparison is made based on operation with equal surface current density, construction losses, and peak-air-gap flux density. Construction and testing of a prototype 500-r/min, 28-kW laboratory machine, converter, and controller are described.<>