Abstract: An improved synchronous tubular electrical machine comprises a radially outer member that has a substantially cylindrical inner surface and radially inner member that is substantially cylindrical and is coaxially disposed within the outer member such that it may move reciprocally relative to the outer member in the axial direction. A plurality of axially spaced circumferential armature coils are electrically insulated from one another and are formed as part of one of the outer member and the inner member. A plurality of axially spaced circumferential superconducting coils are formed as part of the other of the outer member and the inner member. During operation of the tubular machine, each superconducting coil is maintained in a superconducting state and an electrical current is supplied to each superconducting coil in such a manner that the current flowing around each coil is in the opposite direction to the current flowing around the coils adjacent to it.

Abstract: A stator for a tubular electrical generator or motor has a substantially cylindrical inner surface containing a series of axially-spaced slots for receiving the coils of a stator winding. The stator is formed from a plurality of stacked annular laminations that define the slots and the inner surface. The laminations comprise circumferentially-spaced radial slits defining fingers that extend radially outwards from their radially inner edges. The slits and fingers reduce the overall eddy losses in the stator while permitting simple manufacture, simple assembly and high radial thermal conduction for good cooling. In an alternative embodiment, the laminations and their fingers may be replaced by layers of batons of similar radial extent to the laminations.

Abstract: A superconducting electrical machine has rotor and stator assemblies. A first rotor assembly is located to rotate within a stator assembly and is spaced from the stator assembly by an air gap. A second rotor assembly is located to rotate outside the stator assembly and is also spaced from the stator assembly by an air gap. The first and second rotor assemblies have at least one superconducting field winding. The superconducting field windings are formed from a High Temperature Superconducting (HTS) material such as BSCCO-2223 or YBCO, for example. The double rotor assembly configuration provides a new technical effect over conventional rotating superconducting machines having a single rotor assembly.

Abstract: The present invention provides a stator for a tubular electrical machine having a substantially cylindrical inner surface containing a series of axially-spaced slots for receiving the coils of a stator winding. The stator comprises axially successive layers of laminations 2, each layer being formed from a number of curved laminations stacked together in the circumferential direction.

Abstract: An improved synchronous tubular electrical machine comprises a radially outer member that has a substantially cylindrical inner surface and radially inner member that is substantially cylindrical and is coaxially disposed within the outer member such that it may move reciprocally relative to the outer member in the axial direction. A plurality of axially spaced circumferential armature coils are electrically insulated from one another and are formed as part of one of the outer member and the inner member. A plurality of axially spaced circumferential superconducting coils are formed as part of the other of the outer member and the inner member. During operation of the tubular machine, each superconducting coil is maintained in a superconducting state and an electrical current is supplied to each superconducting coil in such a manner that the current flowing around each coil is in the opposite direction to the current flowing around the coils adjacent to it.

Abstract: A stator for a tubular electrical generator or motor has a substantially cylindrical inner surface containing a series of axially-spaced slots for receiving the coils of a stator winding. The stator is formed from a plurality of stacked annular laminations that define the slots and the inner surface. The laminations comprise circumferentially-spaced radial slits defining fingers that extend radially outwards from their radially inner edges. The slits and fingers reduce the overall eddy losses in the stator while permitting simple manufacture, simple assembly and high radial thermal conduction for good cooling. In an alternative embodiment, the laminations and their fingers may be replaced by layers of batons of similar radial extent to the laminations.

Abstract: A stator for a high power density air gap electrical machine comprises an outer annular laminated iron stator core and a stator winding comprising a plurality of coils having linear conductor portions extending substantially parallel to a longitudinal axis of the machine. Support teeth for the coils are fabricated from a non-magnetic material, with each support being interposed between two adjacent ones of the linear conductor portions of the coils. The supports not only supplement the mechanical strength of the winding but also define channels for the flow of coolant to extract heat from the coils.

Abstract: A stator for a high power density air gap electrical machine comprises an outer annular laminated iron stator core and a stator winding comprising a plurality of coils having linear conductor portions extending substantially parallel to a longitudinal axis of the machine. Support teeth for the coils are fabricated from a non-magnetic material, with each support being interposed between two adjacent ones of the linear conductor portions of the coils. The supports not only supplement the mechanical strength of the winding but also define channels for the flow of coolant to extract heat from the coils.