Energy storage system having a flywheel for a vehicle transmission

• US 9,718,343 B2
• Filed: 04/20/2012
• Issued: 08/01/2017
• Est. Priority Date: 04/20/2011
• Status: Expired due to Fees

• Current Assignee: Ricardo UK Limited (Ricardo PLC)
• Original Assignee: Ricardo UK Limited (Ricardo PLC)
• Inventors: Shepherd, Simon, Atkins, Andrew Farquhar, Davis, Jonathan
• Primary Examiner(s): Andrews, Michael
• Application Number:
  US14/112,672
• Publication Number:
  US 20140103761A1
• Time in Patent Office: 1,929 Days
• Field of Search: 310 74, 310 83, 310 99, 310103, 310104
• CPC Class Codes: B60K 2006/262 the motor or generator are used as clutch, e.g. between engine and driveshaft
• CPC Class Codes: B60K 6/105 the accumulator being a flywheel
• CPC Class Codes: B60K 6/30 characterised by chargeable mechanical accumulators, e.g. flywheels
• CPC Class Codes: B60L 50/30 using propulsion power stored mechanically, e.g. in fly-wheels
• CPC Class Codes: B60Y 2400/423 Electromagnetic clutches, e.g. powder type clutches
• CPC Class Codes: B60Y 2400/608 Clutch motors, i.e. having rotating stators
• CPC Class Codes: H02K 49/104 Magnetic couplings consisting of only two coaxial rotary elements, i.e. the driving element and the driven element
• CPC Class Codes: H02K 51/00 Dynamo-electric gears, i.e. dynamo-electric means for transmitting mechanical power from a driving shaft to a driven shaft and comprising structurally interrelated motor and generator parts
• CPC Class Codes: H02K 7/006 Structural association of a motor or generator with the drive train of a motor vehicle
• CPC Class Codes: H02K 7/025 for power storage
• CPC Class Codes: H02K 7/11 with dynamo-electric clutches
• CPC Class Codes: H02K 7/1815 structurally associated with reciprocating piston engines general aspects of generating sets, e.g. housing, F02B63/04
• CPC Class Codes: Y02E 60/16 Mechanical energy storage, e.g. flywheels or pressurised fluids
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

An apparatus is provided comprising a flywheel (112) for storing kinetic energy and an electrical machine (190) mechanically coupled to the flywheel and arranged for conversion between mechanical and electrical energy. The apparatus is arranged for transferring energy between the flywheel and a vehicle transmission via a variable ratio transmission (182). The electrical machine is coupled to the flywheel via a disconnect clutch which comprises a magnetic coupling (116).

Claims

1. An apparatus comprising:

a flywheel for storing kinetic energy, the apparatus arranged for mechanically transferring energy between the flywheel and a vehicle transmission via a variable-ratio transmission; and

an electrical machine arranged for conversion between mechanical energy and electrical energy,

wherein the electrical machine is mechanically coupled to the flywheel via a first disconnect clutch, said first disconnect clutch comprising a magnetic coupling, and

wherein the electrical machine is mechanically coupled to the variable-ratio transmission via a second disconnect clutch.

2. The apparatus of claim 1 wherein the electrical machine is coupled to the flywheel via first and second gears.

3. The apparatus of claim 1 wherein the electrical machine is concentrically arranged on an axis of the flywheel.

4. The apparatus of claim 1 wherein the flywheel is connected to a mechanical coupling member which is longitudinally split into two or more sections, wherein the disconnect clutch selectively couples the split sections.

5. The apparatus of claim 1 wherein the second disconnect clutch comprises a dog-engagement type, or frictional engagement type.

6. The apparatus of claim 1 wherein the second disconnect clutch comprises a magnetic coupling.

7. The apparatus of claim 1 further comprising an electromagnet, wherein said electromagnet is arranged for application of an external magnetic field to the magnetic coupling comprised within the first disconnect clutch.

8. The apparatus of claim 1 wherein the flywheel runs in a vacuum.

9. A method of operating the apparatus of claim 1,

the method comprising storing energy in the flywheel and selectively disconnecting the flywheel from other parts of the apparatus, wherein said other parts comprise the electrical machine and/or the variable-ratio transmissions, wherein the step of selectively disconnecting the flywheel comprises desynchronising the rotation of first and second parts of the magnetic coupling from one another.

10. A method as claimed in claim 9 wherein the first part of the magnetic coupling comprises a low speed rotator and the second part of the magnetic coupling comprises a high speed rotator and wherein the step of desynchronising the rotation of the first and second parts of the magnetic coupling from one another comprises reducing the rotational speed of the low speed rotator below a threshold, wherein said speed reduction is achieved by applying a torque to the magnetic coupling.

11. A method as claimed in claim 10 wherein the torque which is applied to the magnetic coupling exceeds the dynamic torque capacity for the magnetic coupling.

12. A method as claimed in claim 10 wherein the torque is applied to the magnetic gear by any of:

the electrical machine, the variable ratio transmission, a brake or a clutch.

13. A method as claimed in claim 9 further comprising applying an external magnetic field to the magnetic gear during desynchronisation of the first and second parts of the magnetic coupling from one another.

14. A method as claimed in claim 13 wherein the external magnetic field is applied to the magnetic coupling instantaneously or for a finite period of time, which may be predetermined.

15. A method as claimed in claim 13 wherein the external magnetic field is produced using an electromagnet.

16. A method as claimed in claim 9 wherein the step of desynchronising rotation of the first and second parts of the magnetic coupling from one another is achieved by influencing a magnetic field produced by the magnetic coupling using a ferromagnetic shield.

17. A method as claimed in claim 9 wherein the first and second parts of the magnetic coupling comprise first and second rotators with a common rotational axis, wherein the step of desynchronising rotation of the first and second parts of the a magnetic coupling from one another is achieved by physically separating the rotators from one another along said axis, in order to reduce their torque capacity.

18. A method as claimed in claim 9 wherein the method comprises selectively disengaging the first clutch and/or the second clutch during operation of the apparatus.

19. A method as claimed in claim 18 wherein said second disconnect clutch comprises a magnetic coupling.

20. A method as claimed in claim 9 further comprising the step of resynchronising the first and second parts of the magnetic coupling with one another in order to reconnect the flywheel to other parts of the apparatus.

21. The apparatus of claim 1 wherein the electrical machine is at least partially integrated with the flywheel.

22. The apparatus of claim 1 wherein a rotor of the electrical machine is integrated with the flywheel and runs in a vacuum with the flywheel.

23. The apparatus of claim 1, wherein the first disconnect clutch separates the flywheel from the electrical machine such that the flywheel can rotate independently of the electrical machine.

24. The apparatus of claim 1, wherein the second disconnect clutch separates the electrical machine from the variable-ratio transmission, such that the flywheel can rotate with the electrical machine and independently of the variable-ratio transmission.