System and method for improving the vehicle feel, fuel efficiency and performance of a hybrid vehicle

Patent metadata

Field	Value
Publication number	US-9434378-B2
Application number	US-201414581558-A
Country	US
Kind code	B2
Filing date	Dec 23, 2014
Priority date	Dec 23, 2014
Publication date	Sep 6, 2016
Grant date	Sep 6, 2016

Abstract

A system for providing a smoother vehicle response when transitioning a hybrid vehicle having a transmission, a battery and a fuel converter from an EV driving mode to a HV driving mode. The system includes a memory for storing an amount of force to be applied to the transmission for a given pedal input and a given vehicle speed. The system also includes a BMU for determining a state of charge of the battery and for determining a proportional scaling number based on the state of charge. The system also includes an ECU for determining a scaled drive force based on the amount of force to be applied to the transmission and the proportional scaling number and for controlling the utilization of the battery and the fuel converter based on the scaled drive force when the state of charge of the battery is within a low power range.

First claim

What is claimed is:

1. A system for providing a smoother vehicle response when transitioning a hybrid vehicle having a transmission, a battery and a fuel converter from an Electric Vehicle (EV) driving mode to a Hybrid Vehicle (HV) driving mode, comprising:
a memory configured to:
store drive force data including an amount of force to be applied to the transmission corresponding to a given pedal input and a given vehicle speed, and
store proportional scaling data including a proportional scaling number corresponding to a given state of charge of the battery;

a battery management unit configured to:
determine a state of charge of the battery, and
determine, using the stored proportional scaling data from a proportional scaling map, a proportional scaling number based on the state of charge of the battery; and

an electronic control unit configured to:
receive a pedal input and a vehicle speed,
determine, using the stored drive force data, an amount of force to be applied to the transmission based on the received pedal input and the received vehicle speed,
determine a scaled drive force by applying the determined proportional scaling number to the determined amount of force to be applied to the transmission, and
control a utilization of the battery and the fuel converter based on the scaled drive force when the state of charge of the battery is within a low power range for transitioning the hybrid vehicle from the EV driving mode to the HV driving mode.

2. The system of claim 1 , wherein the determined proportional scaling number varies throughout the low power range.

3. The system of claim 2 , wherein the electronic control unit applies a smoothing operation to the determined proportional scaling number throughout the low power range.

4. The system of claim 1 , wherein the fuel converter is an internal combustion engine or a fuel cell.

5. The system of claim 1 , wherein the low power range is between 20 percent and 30 percent of a full state of charge of the battery.

6. The system of claim 1 , wherein the low power range is between 30 percent and 40 percent of a full state of charge of the battery.

7. The system of claim 1 , wherein the proportional scaling number and the corresponding state of charge of the battery have a non-linear relationship in the proportional scaling map.

8. The system of claim 1 , wherein the battery management unit is configured to periodically or continuously determine the state of charge of the battery.

9. A hybrid vehicle for providing a smoother vehicle response when transitioning from an Electric Vehicle (EV) driving mode to a Hybrid Vehicle (HV) driving mode, comprising:
a transmission;
a battery for storing energy and for providing power to the transmission;
a fuel converter for providing energy to the battery and for providing power to the transmission;
a memory for storing drive force data including an amount of force to be applied to the transmission corresponding to a given pedal input and a given vehicle speed and for storing proportional scaling data including a proportional scaling number corresponding to a given state of charge of the battery;
a battery management unit for determining a state of charge of the battery and for determining, using the stored proportional scaling data from a proportional scaling map, a proportional scaling number based on the state of charge of the battery; and
an electronic control unit for receiving a pedal input and a vehicle speed, for determining, using the stored drive force data, an amount of force to be applied to the transmission based on the received pedal input and the received vehicle speed, for determining a scaled drive force by applying the determined proportional scaling number to the determined amount of force to be applied to the transmission, and for controlling a utilization of the battery and the fuel converter based on the scaled drive force when the state of charge of the battery is within a low power range for transitioning the hybrid vehicle from the EV driving mode to the HV driving mode.

10. The hybrid vehicle of claim 9 , wherein the determined proportional scaling number varies throughout the low power range.

11. The hybrid vehicle of claim 10 , wherein the electronic control unit applies a smoothing operation to the determined proportional scaling number throughout the low power range.

12. The hybrid vehicle of claim 9 , wherein the fuel converter is an internal combustion engine or a fuel cell.

13. The hybrid vehicle of claim 9 , wherein the low power range is between 20 percent and 30 percent of a full state of charge of the battery.

14. The hybrid vehicle of claim 9 , wherein the low power range is between 30 percent and 40 percent of a full state of charge of the battery.

15. The hybrid vehicle of claim 9 , wherein the proportional scaling number and the corresponding state of charge of the battery have a non-linear relationship in the proportional scaling map.

16. The hybrid vehicle of claim 9 , wherein the battery management unit is configured to periodically or continuously determine the state of charge of the battery.

17. A method for providing a smoother transition when transitioning from an Electric Vehicle (EV) mode to a Hybrid Vehicle (HV) mode of a hybrid vehicle, comprising:
storing, in a memory coupled to an electronic control unit, drive force data including an amount of force to be applied to a vehicle transmission corresponding to a given vehicle speed and a given pedal input;
storing, in the memory coupled to a battery management unit, proportional scaling data including a proportional scaling number corresponding to a given state of charge of the battery;
determining, using the battery management unit, a state of charge of a battery used to power the vehicle transmission;
determining, using the stored proportional scaling data from a proportional scaling map, a proportional scaling number based on the state of charge of the battery;
determining, using the stored drive force data, an amount of force to be applied to the vehicle transmission based on a received vehicle speed and a received pedal input;
determining, using the electronic control unit, a scaled drive force by applying the determined proportional scaling number to the determined amount of force to be applied to the vehicle transmission; and
controlling, using the electronic control unit, a utilization of the battery and a fuel converter based on the scaled drive force when the state of charge of the battery is within a low power range for transitioning the hybrid vehicle from the EV driving mode to the HV driving mode.

18. The method of claim 17 , further comprising applying a smoothing operation to the determined proportional scaling number throughout the low power range.

19. The method of claim 17 , wherein the fuel converter is an internal combustion engine or a fuel cell.

20. The method of claim 17 , wherein the low power range is between 20 percent and 30 percent of the state of charge of the battery.

21. The method of claim 17 , wherein the low power range is between 30 percent and 40 percent of the state of charge of the battery.

22. The method of claim 17 , wherein the proportional scaling number and the corresponding state of charge of the battery have a non-linear relationship in the proportional scaling map.

23. The method of claim 17 , wherein the determining, using the battery management unit, the state of charge of the battery is performed

Assignees

• Toyota Motor Eng & Mfg North America Inc

Inventors

• Geller Benjamin M

Classifications

• 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

• B60W2510/244

  Charge state · CPC title

• B60W2520/10

  Longitudinal speed · CPC title

• B60W2050/0026

  Lookup tables or parameter maps · 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