Abstract: The invention provides a generator suited for drilling equipment, such as oil and gas applications. A turbine can drive the permanent-magnet, synchronous generator. The generator uses axial flux topology for a stator and a rotor. The design permits a wide airgap between the stator and rotor, so fluid and debris from drilling operations can flow through the generator relatively unobstructed, and the fluid flow can provide a power source to rotate the turbine coupled to the rotor to generate electrical power. The airgap can accommodate non-magnetic sealing plates to provide additional protection to the generator components. The rotor includes a Halbach magnet array of permanent magnets, producing high-intensity magnetic flux in an axial direction. The Halbach magnet array avoids any necessity for the conventional rotor back-iron to return the flux. The proposed generator is intended to generate electric power for drilling equipment, permitting the elimination of costly batteries.

Abstract: A rotary electrical machine which has a plurality of disc-shaped stator stages and a plurality of disc-shaped rotor stages, each of the rotor stages being respectively alternately interleaved with the stator stages. A space is provided between each stator stage and its adjacent rotor stage. Each of the stator stages is provided with at least two stator windings, defining a passage therebetween adjacent windings. A coiled pipe is disposed in or formed integrally with each of the passages in substantially the same plane as the stator stage, such that the outlet of one pipe is coupled with the inlet of the pipe disposed in the adjacent passage. In use, fluid, for example air, helium, water or oil is caused to flow around the coiled pipes in the passages between the stator windings. At the same time, cooling gas, for example, air or helium, is caused to pass through the stator-rotor spaces so as to cool the magnets, etc. and the retention hoops, etc.

Abstract: A retention ring (1) is applied to a disc rotor assembly (3) which comprises a plurality of substantially equiangularly spaced magnets (7). The ring is expanded by driving it over a tapered mandrel (13) onto a rim (5) of the rotor assembly.