US 6,278,197 B1 · Contra-rotating wind turbine system

Abstract

Wind turbine apparatus includes an upright mast with support bearings underlying and rotatably supporting a hub assembly having inner and outer coaxial shafts telescopically related but radially spaced to permit independent rotation about a generally horizontal axis. An armature winding is provided on the outer shaft and a plurality of dielectrically separated magnets are mounted on the inner shaft at a plurality of circumferentially spaced locations. A first set of rotor blades is mounted on the inner shaft at a plurality of circumferentially spaced locations, the rotor blades extending radially away from the axis of rotation and positioned on the inner shaft for rotating the inner shaft in a first direction about the axis of rotation when subjected to wind-induced air flow. A second set of rotor blades is similarly mounted on the outer shaft axially spaced from the first set of rotor blades for rotating the outer shaft about the axis of rotation in an opposite direction. The hub assembly may be selectively positioned in azimuth so that the first set of rotor blades is relatively closer to the wind-induced air flow, or windward, and the second set of rotor blades is relatively farther from the wind-induced air flow, or leeward. Electrical power is generated as the armature winding on the outer shaft and the plurality of magnets on the inner shaft rotate in opposite directions and power transfer apparatus is provided for drawing off the electrical power from the hub assembly to a distant receiver.

Claims17

Dependent claims

Wind turbine apparatus comprising:

a hub assembly including inner and outer coaxial shafts, the inner shaft having an outer peripheral surface, the outer shaft having an inner peripheral surface spaced from the outer peripheral surface of the inner shaft;
first bearing means supporting the outer shaft for rotation about a generally horizontal axis;
second bearing means supporting the inner shaft on the outer shaft for rotation about the axis of rotation;
an armature winding on the outer shaft;
a plurality of magnets on the inner shaft at a plurality of circumferentially spaced locations, each adjacent pair of the magnets being separated with a dielectric spacer;
a first set of rotor blades mounted on the inner shaft at a plurality of circumferentially spaced locations and extending radially away from the axis of rotation, the first set of rotor blades positioned on the inner shaft for rotating the inner shaft in a first direction about the axis of rotation when subjected to wind-induced air flow;
a second set of rotor blades mounted on the outer shaft axially spaced from the first set of rotor blades at a plurality of circumferentially spaced locations and extending radially away from the axis of rotation, the second set of rotor blades positioned on the outer shaft for rotating the outer shaft about the axis of rotation in a second direction opposite the first direction when subjected to wind-induced air flow;
thereby generating electrical power as the armature winding on the outer shaft and the plurality of magnets on the inner shaft rotate in opposite directions.

5 more elements

Wind turbine apparatus comprising:

a hub assembly including inner and outer coaxial shafts, the inner shaft having an outer peripheral surface, the outer shaft having an inner peripheral surface spaced from the outer peripheral surface of the inner shaft;
first bearing means supporting the outer shaft for rotation about a generally horizontal axis;
second bearing means supporting the inner shaft on the outer shaft for rotation about the axis of rotation;
a first set of rotor blades mounted on the inner shaft at a plurality of circumferentially spaced locations and extending radially away from the axis of rotation, the first set of rotor blades positioned on the inner shaft for rotating the inner shaft in a first direction about the axis of rotation when subjected to wind-induced air flow;
and
a second set of rotor blades mounted on the outer shaft axially spaced from the first set of rotor blades at a plurality of circumferentially spaced locations and extending radially away from the axis of rotation, the second set of rotor blades positioned on the outer shaft for rotating the outer shaft about the axis of rotation in a second direction opposite the first direction when subjected to wind-induced air flow.

3 more elements

A method of generating power comprising the steps of:

(a) providing a hub assembly including inner and outer coaxial shafts, the inner shaft having an outer peripheral surface, the outer shaft having an inner peripheral surface spaced from the outer peripheral surface of the inner shaft;
(b) mounting a first set of rotor blades on the inner shaft at a plurality of circumferentially spaced locations so as to extend radially away from the axis of rotation;
(c) mounting a second set of rotor blades on the outer shaft axially spaced from the first set of rotor blades at a plurality of circumferentially spaced locations so as to extend radially away from the axis of rotation;
and
(d) positioning the first and second sets of rotor blades so that wind-induced air flow causes the first set of blades to rotate with the inner shaft in a first direction and so that wind-induced air flow causes the second set of blades to rotate with the outer shaft in a second direction opposite the first direction.

2 more elements

Dependencies are inferred from the claim text.

Contra-rotating wind turbine system

Life of this patent

Contra-rotating wind turbine system

Life of this patent

Abstract

Claims17