Abstract: A permanent magnet electric generator includes a rotor assembly and a stator assembly. The rotor assembly has axially disposed annular outer and inner rings concentric with an axis of rotation. A plurality of magnets is disposed on the outer ring, each magnet having a north pole and a south pole. The permanent magnets are aligned with the axis of rotation, and adjacent magnets have alternating polarity. The stator assembly includes a plurality of stator blocks aligned to form an annular ring-shaped stator member retained by a stator frame. The stator member is configured to be at least partially disposed inside the rotor assembly and is circumferentially encircled by the rotor assembly.

Abstract: An electric arc welding system is powered by a power generator with a rotor assembly circumferentially surrounding a stator assembly. The arc welding system generates a three phase AC current, which is converted into a DC current by a converter. An electrode coupled to the converter receives the DC current, wherein a welding arc is created between the electrode and a workpiece. A controller is coupled to the converter. The controller is operable to apply a control signal to the converter to cause the converter to vary the magnitude of the DC current.

Abstract: A permanent magnet electric generator includes a rotor assembly and a stator assembly. The rotor assembly has axially disposed annular outer and inner rings concentric with an axis of rotation. The inner ring has a radius less than the radius of the outer ring. The inner ring is disposed inside the outer ring. A rotor frame is attached to the inner ring and the outer ring. The rotor frame defines a radial gap between the inner and the outer rings. A rotor hub is concentric with the axis of rotation and is disposed inside the inner ring. The rotor hub is coupled to the inner ring by a hub frame that is mounted on the rotor hub. The rotor hub is adapted to be rotationally coupled to a shaft for rotating the rotor assembly. A plurality of magnets is disposed on the outer ring, each magnet having a north pole and a south pole. The permanent magnets are aligned with the axis of rotation, and adjacent magnets have alternating polarity.