Hybrid Vehicle Propulsion Systems And Methods

Patent metadata

Field	Value
Publication number	US-2018050686-A1
Application number	US-201615239010-A
Country	US
Kind code	A1
Filing date	Aug 17, 2016
Priority date	Aug 17, 2016
Publication date	Feb 22, 2018
Grant date	—

Abstract

A hybrid vehicle propulsion includes an engine and a first electric machine, where each is configured to selectively provide torque to propel the vehicle. The propulsion system also includes a second electric machine coupled to the engine to provide torque to start the engine from an inactive state. A high-voltage power source is configured to power both of the first electric machine and the second electric machine over a high-voltage bus. The propulsion system further includes a controller programmed to deactivate the engine and propel the vehicle using the first electric machine in response to the vehicle being driven at a steady-state speed for a predetermined duration of time. The controller is also programmed to restart the engine using the second electric machine powered by the high-voltage power source.

First claim

What is claimed is:

1 . A hybrid vehicle propulsion system comprising:
an engine and a first electric machine each configured to selectively provide torque to propel the vehicle; a second electric machine coupled to the engine to provide torque to start the engine from an inactive state; a high-voltage power source to power both of the first electric machine and the second electric machine over a high-voltage bus; and a controller programmed to
deactivate the engine and propel the vehicle using the first electric machine in response to the vehicle being driven at a steady-state speed for a predetermined duration of time, and
restart the engine using the second electric machine powered by the high-voltage power source.

2 . The hybrid vehicle propulsion system of claim 1 further comprising a low-voltage power source, wherein the high-voltage power source and the low-voltage power source are integrated as part of a single energy storage module.

3 . The hybrid vehicle propulsion system of claim 1 wherein the controller is further programmed to select one of a plurality of drive modes based on at least one of a vehicle speed, a torque demand, a SOC of the high-voltage power source, and a SOC of a low-voltage power source.

4 . The hybrid vehicle propulsion system of claim 1 further comprising a DC-DC converter to exchange power flow between the high-voltage bus and a low-voltage bus, wherein the DC-DC converter includes a fault mode to power the second electric machine using a low-voltage power source in response to a fault associated with the high-voltage power source.

5 . The hybrid vehicle propulsion system of claim 1 further comprising at least one vehicle accessory driven by a third electric machine, wherein the third electric machine is selectively powered by one of the high-voltage power source and a low-voltage power source.

6 . The hybrid vehicle propulsion system of claim 1 wherein the controller is further programmed to operate a vehicle HVAC system using power from the high-voltage power source while the engine is in an inactive state.

7 . The hybrid vehicle propulsion system of claim 1 wherein the second electric machine is a brushless permanent magnet motor having an electronic commutator comprising solid state switches and an imbedded electric machine controller.

8 . A method of operating a vehicle propulsion system comprising:
selectively operating at least one of a combustion engine and a first electric machine to provide a propulsion torque, the first electric machine being powered by a high-voltage power source; deactivating the combustion engine in response to the vehicle being operated at a speed corresponding to a power draw less than a power threshold for a predetermined amount of time; and in response to a torque demand that is greater than a torque demand threshold, restarting the combustion engine using torque output from a second electric machine powered by the high-voltage power source.

9 . The method of claim 8 further comprising powering at least one of the first electric machine and the second electric machine using a low-voltage power source in response to a fault condition associated with the high-voltage power source.

10 . The method of claim 8 further comprising operating the second electric machine as a generator in response to a fault condition associated with the first electric machine.

11 . The method of claim 8 further comprising operating the first electric machine as a generator to provide power to the high-voltage power source in response to a vehicle coast condition.

12 . The method of claim 8 further comprising deactivating the combustion engine in response to the vehicle being at a standstill for a predetermined amount of time.

13 . The method of claim 8 further comprising generating a state of health prognosis signal for at least one of the first electric machine, the second electric machine, and the high-voltage power source, and transmitting the prognosis signal to an off-board processor.

14 . The method of claim 8 further comprising powering at least one vehicle accessory component using torque output from the first electric machine while the engine is deactivated.

15 . The method of claim 8 further comprising:
receiving a signal indicative of at least one available parking space;
providing a user interface to inform a user of the at least one available parking space;
generating at least one proximity signal indicative of at least one object in a vicinity of the vehicle; and
in response to a user prompt, automatically operating the first electric machine to propel the vehicle to the target parking space.

16 . A vehicle propulsion system comprising:
an engine and a first electric machine each configured to selectively provide torque to propel the vehicle; a second electric machine coupled to the engine to provide torque to start the engine from an inactive state; a high-voltage power source to power both of the first electric machine and the second electric machine over a high-voltage bus; and a controller programmed to
start the engine using cranking torque output from the second electric machine powered by the high-voltage power source,
operate both of the first electric machine and the combustion engine to propel the vehicle in response to an acceleration demand greater than an acceleration threshold,
operate the first electric machine as a generator to restore charge at the high-voltage power source in response to a vehicle deceleration condition, and
deactivate the engine and operate the first electric machine to propel the vehicle in response to the vehicle being operated at a speed causing a power draw less than a predetermined power limit.

17 . The vehicle propulsion system of claim 16 wherein the controller is further programmed to operate the first electric machine to automatically propel the vehicle to a user-selected parking space based on information transmitted over a wireless network indicative of at least one available parking space.

18 . The vehicle propulsion system of claim 16 wherein the controller is further programmed to select one of a plurality of drive modes based on at least one of a vehicle speed, a torque demand, and a SOC of the high-voltage power source.

19 . The vehicle propulsion system of claim 16 further comprising a DC-DC converter to exchange power flow between the low-voltage bus and a high-voltage bus, wherein the DC-DC converter includes a fault mode to power the second electric machine using a low-voltage power source in response to a fault associated with the high-voltage power source.

20 . The vehicle propulsion system of claim 16 further comprising a low-voltage power source, wherein the high-voltage power source and the low-voltage power source are integrated as part of a single energy storage module.

21 . The vehicle propulsion system of claim 16 wherein the controller is further programmed to generating a state of health prognosis signal for at least one of the first electric machine, the second electric machine based on a model stored in a memory at the controller.

Assignees

• Gm Global Tech Operations Llc

Inventors

• Atluri Venkata Prasad
• Bucknor Norman K
• Conell Robert S
• Gopalakrishnan Suresh
• Hao Lei
• Lee Chunhao J
• Lahr Derek F
• Li Dongxu
• Li Shifang
• Namuduri Chandra S
• Nehl Thomas W
• Omekanda Avoki M
• Powell Jr Bob R
• Prasad Rashmi
• Samie Farzad
• Shidore Neeraj S
• Sullivan Aaron M

Classifications

• B60Y2300/18066

  Coasting · CPC title

• B60K6/48

  Parallel type · CPC title

• B60W20/40 Primary

  Controlling the engagement or disengagement of prime movers, e.g. for transition between prime movers {(power-up or power-down of the driveline B60W30/192)} · CPC title

• F02N11/04

  the motors being associated with current generators · CPC title

• B60W20/13

  in order to stay within battery power input or output limits; in order to prevent overcharging or battery depletion · CPC title