Multi-phase motor drives, including induction motors and permanent magnet motors, are used in a wide variety of applications and offer fault-tolerant operation under faults in motor windings and converter switches. Symmetrical multi-fed drives based on three-phase modules are of special interest in safety critical applications. They offer simple control under a fault condition. However, even a single open-circuit fault of one switch or winding will cause complete interruption of a faulty module.
Rensselaer researchers have designed a convenient and inexpensive linear permanent magnet machine solution for transportation, conveyance, and other applications. When designed for short-strokes, the machine is very robust and rugged, and exhibits excellent performance characteristics such as very high thrust density, low ripples, and normal forces. Traditionally, linear PM machines had the armature windings in the translator and the PMs in the stator or vice-versa. This novel design allows both the field and armature excitations in the same part of the machine.
This technology relates to an actuator motor with fast dynamic response capability, high torque density, high efficiency, and improved thermal and mechanical stability at high speed while minimizing weight. According to one example, an actuator motor includes a rotor shaft with an array of permanent magnets attached according to a Halbach array configuration. A stator includes windings that induce a torque on the rotor shaft when rotating magnetic fields interact with the optimized magnetic flux distributions of the magnets of the Halbach array.