Wind turbine generator rotor arrangement

A rotor arrangement for a wind turbine generator, the rotor arrangement comprising:

• a cylindrical ring structure, defining a central hollow portion, arranged to rotate around a rotational axis, the cylindrical ring structure comprising:
• a plurality of ring-shaped permanent magnet packages arranged coaxially around the rotational axis,
• a plurality of tie rods extending axially through the plurality of permanent magnet packages to join the plurality of permanent magnet packages together;
• and between at least one axially adjacent pair of the plurality of permanent magnet packages, a plurality of circumferentially arranged spacer components, each of the plurality of spacer components being arranged on a respective one of the plurality of tie rods and being configured to hold that pair of permanent magnet packages apart to define a pair of radial channels that extend between the pair of permanent magnet packages, and
• a plurality of impeller vanes, each impeller vane extending radially inward from an inner circumferential edge of the cylindrical ring structure to define a leading edge within the central hollow portion of the cylindrical ring structure, the leading edge being configured to meet oncoming air as the rotor arrangement rotates, in use, and thereby to cause a flow of air in a radial direction through the respective pair of radial channels.

A rotor arrangement for a wind turbine generator, the rotor arrangement comprising a cylindrical ring structure arranged to rotate around a rotational axis, the cylindrical ring structure comprising:

• a plurality of ring-shaped permanent magnet packages arranged coaxially around the rotational axis, at least one ring-shaped permanent magnet package of the plurality of packages defining an inner circumferential edge,
• a plurality of tie rods extending axially through the plurality of permanent magnet packages to join the plurality of permanent magnet packages together;
• and
• one or more spacer components, located adjacent to an axially outer end package of the plurality of ring-shaped permanent magnet packages, against which one or more retaining elements of the rotor arrangement bear to retain the permanent magnet packages on the plurality of tie rods,
• wherein at least one of the one or more spacer components includes an impeller element that extends radially outward from a leading edge to a trailing edge, the leading edge of the impeller element protruding radially inward beyond the inner circumferential edge and being configured to meet oncoming air as the rotor rotates and to guide the oncoming air in a radial direction to flow from the leading edge to the trailing edge across the axially outer end package.

A rotor arrangement for a wind turbine generator, the rotor arrangement comprising a cylindrical ring structure arranged to rotate around a rotational axis, the cylindrical ring structure comprising:

• a plurality of ring-shaped permanent magnet packages arranged coaxially around the rotational axis, at least one pair of adjacent ring-shaped permanent magnet packages being spaced apart from one another,
• a plurality of tie rods extending axially through the plurality of permanent magnet packages to join the plurality of permanent magnet packages together;
• and
• one or more impeller vanes extending radially inward from an inner circumferential edge of the cylindrical ring structure, for causing radial flow of air between the at least one pair of adjacent, spaced apart ring-shaped permanent magnet packages as the rotor arrangement rotates.

A rotor arrangement for a wind turbine generator, the rotor arrangement comprising a cylindrical ring structure arranged to rotate around a rotational axis, the cylindrical ring structure comprising:

• a plurality of ring-shaped permanent magnet packages arranged coaxially around the rotational axis,
• a plurality of tie rods extending axially through the plurality of permanent magnet packages to join the plurality of permanent magnet packages together;
• and
• one or more spacer components located between at least one axially adjacent pair of the plurality of permanent magnet packages to space the respective pair of permanent magnet packages apart,
• wherein the one or more spacer components are configured to act as an impeller as the rotor rotates, in use, thereby to cause air to flow in a radial direction, with respect to the rotational axis of the rotor arrangement, between the at least one axially adjacent pair of permanent magnet packages,
• wherein the one or more spacer components comprise a plurality of circumferentially arranged spacer components, each of the plurality of spacer components being arranged on a respective one of the plurality of tie rods,
• wherein each of the plurality of circumferentially arranged spacer components is shaped to define an impeller element for causing the radial flow of air,
• wherein each impeller element is elongate and extends from a leading edge to a radially outer trailing edge, defining a longitudinal axis between the leading and trailing edges, and
• wherein each impeller element is shaped so that the leading edge protrudes radially inward, beyond an inner circumferential edge of the adjacent permanent magnet package, to meet oncoming air as the rotor arrangement rotates.

A rotor arrangement for a wind turbine generator, the rotor arrangement comprising a cylindrical ring structure arranged to rotate around a rotational axis, the cylindrical ring structure comprising:

• a plurality of ring-shaped permanent magnet packages arranged coaxially around the rotational axis,
• a plurality of tie rods extending axially through the plurality of permanent magnet packages to join the plurality of permanent magnet packages together;
• one or more spacer components located between at least one axially adjacent pair of the plurality of permanent magnet packages to space the respective pair of permanent magnet packages apart;
• and
• one or more impeller vanes extending radially inward from an inner circumferential edge of the cylindrical ring structure, for causing the radial flow of air as the rotor arrangement rotates,
• wherein at least one of the one or more spacer components includes an impeller element that extends radially outward from a leading edge to a trailing edge, the leading edge of the impeller element being configured to meet oncoming air as the rotor rotates and to guide the oncoming air in a radial direction to flow from the leading edge to the trailing edge between the at least one axially adjacent pair of permanent magnet packages, and
• wherein each impeller vane is arranged in a complementary manner to a respective one of the impeller elements of the one or more spacer components so that, collectively, the impeller vane and the impeller element cause the radial flow of air as the rotor arrangement rotates.

A rotor arrangement for a wind turbine generator, the rotor arrangement comprising a cylindrical ring structure arranged to rotate around a rotational axis, the cylindrical ring structure comprising:

• a plurality of ring-shaped permanent magnet packages arranged coaxially around the rotational axis,
• a plurality of tie rods extending axially through the plurality of permanent magnet packages to join the plurality of permanent magnet packages together;
• one or more spacer components located between at least one axially adjacent pair of the plurality of permanent magnet packages to space the respective pair of permanent magnet packages apart;
• and
• one or more impeller vanes extending radially inward from an inner circumferential edge of the cylindrical ring structure, for causing the radial flow of air as the rotor arrangement rotates,
• wherein at least one of the one or more spacer components includes an impeller element that extends radially outward from a leading edge to a trailing edge, the leading edge of the impeller element being configured to meet oncoming air as the rotor rotates and to guide the oncoming air in a radial direction to flow from the leading edge to the trailing edge between the at least one axially adjacent pair of permanent magnet packages, and
• wherein each impeller vane extends axially along the length of the cylindrical ring structure.