Energy storage and conversion apparatus

• US 5,912,519 A
• Filed: 04/07/1998
• Issued: 06/15/1999
• Est. Priority Date: 08/08/1994
• Status: Expired due to Fees

• Current Assignee: British Nuclear Technology
• Original Assignee: British Nuclear Technology
• Inventors: Horner, Roger Eric, Crombie, Ian, Barker, Geoffrey Martin, Hayward, David Stephen, Tarrant, Colin David
• Primary Examiner(s): LABALLE, CLAYTON E
• Application Number:
  US09/055,769
• Time in Patent Office: 434 Days
• Field of Search: 310/74, 310/90.5, 310/157, 310/261, 310/156, 74/572
• US Class Current: 310/74
• CPC Class Codes: F16C 2361/55 Flywheel systems in general F16F15/00
• CPC Class Codes: F16C 32/0423 with permanent magnets on both parts repelling each other
• CPC Class Codes: F16F 15/30 Flywheels F16F15/16, F16F15/28 take precedence; suppression of vibrations in rotating systems using elastic members or friction-damping members moving with the system, i.e. split flywheels or single masses connected to a hub by elastic members or friction-damping members F16F15/12; rotary-body aspects in general F16C13/00, F16C15/00
• CPC Class Codes: F16F 15/305 made of plastics, e.g. fibre reinforced plastics [FRP] , i.e. characterised by their special construction from such materials
• CPC Class Codes: F16F 15/3156 Arrangement of the bearings
• CPC Class Codes: H02K 1/2791 Surface mounted magnets; Inset magnets
• CPC Class Codes: H02K 16/00 Machines with more than one rotor or stator machines for transmitting mechanical power from a driving shaft to a driven shaft and comprising structurally interrelated motor and generator parts H02K51/00; permanent magnet machines with multiple rotors or stators relatively rotated for vectorially combining the excitation fields or the armature voltages H02K21/029
• CPC Class Codes: H02K 5/04 Casings or enclosures characterised by the shape, form or construction thereof
• CPC Class Codes: H02K 7/025 for power storage
• CPC Class Codes: H02K 7/086 radially supporting the rotor around a fixed spindle; radially supporting the rotor directly H02K7/09 takes precedence
• CPC Class Codes: H02K 7/09 with magnetic bearings
• CPC Class Codes: Y02E 60/16 Mechanical energy storage, e.g. flywheels or pressurised fluids

Abstract

An energy storage and conversion apparatus (1) comprising a containment (5) defining a vacuum chamber (7), a substantially vertical shaft within the vacuum chamber (7), a stator (11) on the shaft (9), and a cylindrical rotor (13) which, in is driven by the stator (11) to store energy as kinetic energy of the rotor (13) and acts with the stator (11) as a generator to release energy, wherein the rotor (13) is supported by the shaft (9) via an end cap (29), positioned at the upper end of the cylindrical rotor (13), which engages the shaft (9). The rotor (13) is suspended from a pin bearing (31) which is attached to an end cap (29). The pin bearing (31) sits in a bearing cup (37) mounted in a damper (39) at the end of the shaft (9). A magnet bearing (43) is provided at the lower end of the rotor (13) to assist in positioning the rotor (13) relative to the stator (11).

Claims

1. An energy storage and conversion apparatus comprising

a containment defining a vacuum chamber,

a substantially vertical shaft within the vacuum chamber,

a stator on the shaft, and

a cylindrical rotor which, in use, is driven by the stator to store energy as kinetic energy of the rotor and acts with the stator as a generator to release energy,

characterized in that the rotor comprises an inner layer of glass fibre and on outer layer of carbon fibre, the thickness of the inner layer being about two thirds of the thickness of the complete rotor.

2. An apparatus as claimed in claim 1, wherein the inner layer contains a material magnetized to form a multipolar magnetization for interaction with the stator, during use.

3. An apparatus as claimed in claim 2, wherein the magnetized material is a powder introduced into the inner layer during manufacture.

4. An apparatus as claimed in claim 2, wherein the magnetized material is ferrite or NdFeB.

5. An apparatus as claimed in claim 2, wherein the magnetized material extends from the inner surface of the inner layer to about half way through the inner layer.

6. An apparatus as claimed in claim 1, wherein the inner layer contains a material magnetized to form at least one homo-polar radial magnetization for interaction with a magnet mounted on the shaft to produce a bearing for the rotor.

7. An apparatus as claimed in claim 1, wherein the inner and outer layers are strain matched to prevent separation during use.

8. An apparatus as claimed in claim 1, wherein an end cap of the rotor assists in suspending the rotor on the shaft.

9. An apparatus as claimed in claim 1, wherein the speed of the rotor is measured to provide an output indicative of the energy stored in the rotor.

10. An apparatus as claimed in claim 9, wherein a visual output is provided giving the energy available from the apparatus in real time.

11. An apparatus as claimed in claim 9, wherein the speed of the rotor is measured by monitoring the switching frequency of the motor/generator power electronics.

12. An apparatus as claimed in claim 1 wherein an external circuit is provided through which gases in the containment are driven by a pressure difference, the external circuit including a device for removing gas thereby improving the vacuum within the containment.