Hybrid engine system

1. A system for power transfer, comprising:

a primary internal combustion engine;

a secondary internal combustion engine;

a flywheel;

a first clutch having first and second portions; and

a second clutch having first and second portions wherein:

the first and second clutches each have an engaged position in which the first and second portions of the clutch rotate together and a disengaged position in which the first portion of the clutch rotates independently of the second portion of the clutch;

axes of rotation of the primary engine, the secondary engine, the flywheel, the first clutch, and the second clutch are substantially collinear;

the first portion of the first clutch is coupled to the primary engine such that the first portion of the first clutch and the primary engine rotate together;

the second portion of the first clutch is coupled to the flywheel such that the second portion of the first clutch and the flywheel rotate together;

the second clutch is disposed between the primary and secondary engines;

the first portion of the second clutch is coupled to the secondary engine such that the first portion of the second clutch and the secondary engine rotate together; and

the second portion of the second clutch is coupled to the primary engine such that the second portion of the second clutch and the primary engine rotate together.

2. The system of claim 1 , further comprising:

permanent magnets affixed to a surface of the flywheel; and

a stator having coils located proximate the permanent magnets and separated from the permanent magnets by a gap.

3. The system of claim 2 , further comprising:

a controller coupled to the coils wherein the flywheel is capable of operating as a kinetic storage device, a motor, and a generator depending on the current in the coils.

4. The system of claim 1 , further comprising:

a third clutch having an axis of rotation collinear with axes of rotation of the first and second clutches, the third clutch having a first portion coupled to the flywheel and a second portion coupled to a power takeoff and the third clutch selectably engages the flywheel with the power takeoff.

5. The system of claim 4 , further comprising:

a transmission coupled to the power takeoff wherein an axis of rotation of the transmission is offset from the axis of rotation of the power takeoff.

6. The system of claim 1 wherein: the flywheel is disposed on a side of the primary engine distal from the secondary engine.

7. The system of claim 1 , further comprising:

permanent magnets affixed to a surface of the flywheel;

a stator having coils located proximate the permanent magnets and separated from the permanent magnets by a gap; and

a controller electronically coupled to:

the coils to control current through the coils so that the flywheel acts as one of a motor and a generator;

the first clutch to command engagement and disengagement of the first clutch; and

the second clutch to command engagement and disengagement of the second clutch.

8. The system of claim 7 wherein, upon receiving a starting request:

the controller commands the flywheel to rotate by commanding the flywheel to act as a motor and controlling the current in the coils;

the controller commands the first clutch to engage when the flywheel is rotating at a speed greater than a first threshold speed; and

the controller commands the primary engine to start when the engine is rotating at a speed greater than a second threshold speed.

9. The system of claim 8 , wherein:

the controller commands one of the primary and secondary engines to operate and commands the other of the primary and secondary engines to be deactivated when demanded power from the system is in a first range;

the controller commands both the primary and secondary engines to operate when demanded power from the system is in a second range; and

the controller bases a transition from the first range and the second range at least on minimizing overall brake specific fuel consumption (bsfc) of the primary and secondary engines.

10. The system of claim 4 , further comprising:

a transmission; and

a third clutch selectably coupling the transmission and the flywheel.

11. A coupling system for power transfer, comprising:

a first internal combustion engine;

a second internal combustion engine;

a motor-generator;

a first coupler selectably coupling the first engine with the second engine; and

a second coupler selectably coupling the second engine with the motor generator wherein axes of rotation of the first engine, the second engine, the motor-generator the first coupler, and the second coupler are substantially coincident; and when both of the first and second couplers are engaged, the first engine, the second engine, the motor-generator, the first coupler, and the second coupler rotate synchronously;

a third coupler; and

a power takeoff selectably coupable to the motor-generator via the third coupler.

12. The system of claim 11 wherein the first and second couplers are clutches and the first and second couplers are one of electronically and hydraulically actuated.

13. The system of claim 11 wherein the motor-generator further comprises a kinetic energy storage device.

14. The system of claim 11 wherein the first engine comprises a first opposed-piston, opposed-cylinder engine and the second engine comprises a second opposed-piston, opposed-cylinder engine.

15. The system of claim 11 wherein the first, second, and third couplers comprise electronically-controlled clutches.

16. The system of claim 15 , further comprising:

a transmission having an axis of rotation displaced from the axis of rotation of the power takeoff; and

an element coupling the transmission with the power takeoff wherein the element is one of a belt, a chain, and a gear.

17. A system for power transfer, comprising:

a primary internal combustion engine;

a secondary internal combustion engine;

a motor-generator; and

a first clutch;

a second clutch wherein:

axes of rotation of the primary engine, the secondary engine, the motor-generator, the first clutch, and the second clutch are substantially collinear;

the first clutch is disposed between the primary engine and the motor-generator;

a first portion of the first clutch is coupled to the primary engine such that the first portion of the first clutch and the primary engine rotate together;

a second portion of the first clutch is coupled to the motor-generator such that the second portion of the first clutch and the motor-generator rotate together;

the second clutch is disposed between the primary and secondary engines;

a first portion of the second clutch is coupled to the secondary engine such that the first portion of the second clutch and the secondary engine rotate together;

the first and second clutches have an engaged position in which the first and second portions of the clutch rotate together and a disengaged position in which the first portion of the clutch rotates independently of the second portion of the clutch;

when the motor-generator is operated as a motor and the first clutch is engaged, the primary engine is caused to rotate; and

when the second clutch is engaged, the primary and secondary engines rotate synchronously.

18. The system of claim 17 , further comprising:

a transmission; and

a third clutch selectably coupling the transmission and the flywheel.

19. The system of claim 17 wherein the motor-generator comprises a flywheel with magnets affixed to the flywheel and coils of a stator separated from the magnets by a gap.

20. The system of claim 17 , further comprising:

a controller electronically coupled to the first and second clutches and the motor-generator, wherein upon receiving a starting request:

the controller commands the motor-generator to rotate;

the controller commands the first clutch to engage when the motor-generator is rotating at a speed greater than a first threshold speed; and

the controller commands the primary engine to start when the primary engine is rotating at a speed greater than a second threshold speed.

21. The system of claim 18 , further comprising:

a controller electronically coupled to the first and second clutches, the motor-generator, and the third clutch.