Vehicle drive system, power management device, and method for managing power
A power distribution system for a hybrid vehicle having an engine is disclosed. The power distribution system includes an electric motor/generator, a vehicle accessory drive system comprising a first accessory, and a power distribution apparatus. The power distribution apparatus includes a first power transfer member comprising a first shaft, the first shaft being configured to transfer power to the engine and from the engine. The power distribution apparatus further includes a second power transfer member comprising a second shaft, the second shaft being configured to transfer power to the motor/generator and from the motor/generator. The power distribution apparatus further includes a third power transfer member comprising a third shaft, the third shaft being configured to transfer power to the accessory drive system to drive the first accessory. The power distribution apparatus further includes a first clutch and a second clutch.
1. A power distribution system for a hybrid vehicle having an engine, the power distribution system comprising:
an electric motor/generator;
a vehicle accessory drive system comprising a first accessory; and
a power distribution apparatus in operable communication with the engine, the electric motor/generator, and the vehicle accessory drive system, the power distribution apparatus comprising:
a first power transfer member comprising a first shaft, the first shaft being configured to transfer power to the engine and from the engine;
a second power transfer member comprising a second shaft, the second shaft being configured to transfer power to the motor/generator and from the motor/generator;
a third power transfer member comprising a third shaft, the third shaft being configured to transfer power to the accessory drive system to drive the first accessory; and
a first clutch configured to rotationally couple any two of the first shaft, the second shaft, and the third shaft;
wherein the electric motor/generator, the engine, or a combination of the electric motor/generator and the engine, can supply power through the power distribution apparatus to the accessory drive system, and
wherein the third shaft of the power distribution apparatus is configured to operate at a predetermined velocity during multiple vehicle operating modes, wherein the predetermined velocity is controlled by the motor/generator and is independent of the motor/generator operation and is independent of the engine velocity.
2. The power distribution system of claim 1 , wherein the vehicle accessory drive system further comprises a second vehicle accessory.
3. The power distribution system of claim 2 , wherein power is delivered to the first and second vehicle accessories through pulleys operably communicating with a belt, the belt receiving power from the third shaft.
4. The power distribution system of claim 1 , wherein the first accessory comprises an air conditioner system, a power steering system, a power braking system, an oil pump, or a coolant pump.
5. The power distribution system of claim 1 , wherein the third shaft is configured to rotate at a velocity of from 500 to 6,000 revolutions per minute when the engine operates at a velocity of from 0 to 7,000 revolutions per minute.
6. The power distribution system of claim 1 , wherein the power distribution apparatus comprises a first planetary gear system.
7. The power distribution system of claim 6 , wherein the first power transfer member comprises a planet gear carrier, the second power transfer member comprises a sun gear, and the third power transfer member comprises a ring gear.
8. The power distribution system of claim 7 , further comprising a second planetary gear system configured to change a torque level between the motor/generator and the second power transfer member of the power distribution apparatus, the second planetary gear system comprising a second ring gear continuously connected to the second shaft, and a second sun gear continuously connected to a fourth shaft, the fourth shaft being configured to transfer power to and from the electric motor/generator.
9. The power distribution system of claim 7 , wherein the ring gear to the sun gear tooth ratio is from about 1.5 to about 3.0:1.
10. The power distribution system of claim 6 , wherein the first power transfer member comprises a ring gear, the second power transfer member comprises a sun gear, and the third power transfer member comprises a planet gear carrier.
11. The power distribution system of claim 1 , wherein a first torque conversion device is disposed between the power distribution apparatus and the engine, the motor/generator, or the accessory drive system.
12. The power distribution system of claim 11 , wherein a second torque conversion device is disposed between the power distribution apparatus and the engine, the motor/generator, or the accessory drive system.
13. The power distribution system of claim 11 , wherein the torque conversion device comprises a gear system.
14. The power distribution system of claim 11 , wherein the torque conversion device comprises a second planetary gear system.
15. The power distribution system of claim 11 , wherein the torque conversion device comprises a belt and pulley system.
16. A power distribution system for a hybrid vehicle having an engine, the power distribution system comprising:
an electric motor/generator;
a vehicle accessory drive system comprising a first accessory; and
a power distribution apparatus in operable communication with the engine, the electric motor/generator, and the vehicle accessory drive system, the power distribution apparatus comprising:
a first power transfer member comprising a first shaft, the first shaft being configured to transfer power to the engine and from the engine;
a second power transfer member comprising a second shaft, the second shaft being configured to transfer power to the motor/generator and from the motor/generator;
a third power transfer member comprising a third shaft, the third shaft being configured to transfer power to the accessory drive system to drive the first accessory; and
a first clutch configured to rotationally couple any two of the first shaft, the second shaft, and the third shaft;
a second clutch configured to prevent power from being transferred from the power distribution apparatus to the engine in a first direction;
wherein the electric motor/generator, the engine, or a combination of the electric motor/generator and the engine, can supply power through the power distribution apparatus to the accessory drive system, and
wherein the third shaft of the power distribution apparatus is configured to operate at a predetermined velocity, wherein the predetermined velocity is independent of the engine velocity.
17. The power distribution system of claim 16 , wherein the second clutch is configured to engage the first power transfer member to prevent power transfer to the engine in the first direction.
18. The power distribution system of claim 1 , wherein power is transferred to the accessory drive system at a predetermined power level of 0.1 horsepower to 10 horsepower.