Battery voltage control device and battery voltage control method

Patent metadata

Field	Value
Publication number	US-9783069-B2
Application number	US-201514625460-A
Country	US
Kind code	B2
Filing date	Feb 18, 2015
Priority date	Feb 18, 2014
Publication date	Oct 10, 2017
Grant date	Oct 10, 2017

Abstract

A battery voltage control device includes a step-up module that steps up a voltage of a battery and applies the voltage to a driving motor, an image analysis processing module that acquires and analyzes a piece of image information of an outside of a vehicle that is obtained through imaging, and driving state forecast module that forecasts a driving state including starting or stopping of the vehicle based on a piece of environment information of the outside of the vehicle that is obtained through analysis of the piece of image information and controls step-up by the step-up module based on the forecast driving state.

First claim

The invention claimed is:

1. A battery voltage control device, comprising:
a step-up module configured to step-up a voltage of a battery and apply the voltage to a driving motor;
an outside-of-vehicle monitoring module configured to monitor an outside of a vehicle and acquire environment information of the outside of the vehicle; and
a step-up control module configured to control step-up by the step-up module based on the acquired environment information of the outside of the vehicle.

2. The battery voltage control device according to claim 1 , further comprising:
a driving state forecast module configured to forecast a driving state including start or stop of the vehicle based on the environment information of the outside of the vehicle,
wherein the step-up control module is further configured to control step-up by the step-up module based on the forecast driving state.

3. The battery voltage control device according to claim 1 , wherein the outside-of-vehicle monitoring module comprises an image analysis processing module configured to acquire and analyze image information of the outside of the vehicle obtained through imaging, and acquire the environment information based on the image information.

4. The battery voltage control device according to claim 3 , wherein the image analysis processing module is further configured to acquire the image information from a stereo camera assembly.

5. The battery voltage control device according to claim 2 , wherein the driving state forecast module is further configured to forecast start or stop of the vehicle based on the environment information that indicates a lighting state of a traffic signal ahead of the vehicle.

6. The battery voltage control device according to claim 2 , wherein the driving state forecast module is further configured to forecast start or stop of the vehicle based on the environment information that indicates a lighting state of a brake lamp of a preceding vehicle ahead of the vehicle.

7. The battery voltage control device according to claim 1 , further comprising:
a travel mode acquisition module configured to acquire a travel mode that relates to an output characteristic of the driving motor; and
an accelerator opening degree acquisition module configured to acquire an accelerator opening degree, wherein the step-up control module is further configured to control a target step-up voltage of step-up by the step-up module based on the travel mode and the accelerator opening degree.

8. The battery voltage control device according to claim 7 , wherein the step-up control module is further configured to set the target step-up voltage to be higher than a necessary step-up voltage necessary for the driving motor to output a target driving force, and change a margin of the target step-up voltage with respect to the necessary step-up voltage according to the travel mode.

9. The battery voltage control device according to claim 7 , wherein the step-up control module comprises a future driver-required driving force computation module configured to compute a future driver-required driving force based on the travel mode and the accelerator opening degree, and a target step-up voltage computation module configured to compute the target step-up voltage based on the future driver-required driving force.

10. The battery voltage control device according to claim 9 , wherein the future driver-required driving force computation module is further configured to compute a driver-required driving force based on a map on which a relation between the accelerator opening degree and a required driving force is defined for each of the driving modes, and compute the future driver-required driving force based on the driver-required driving force.

11. The battery voltage control device according to claim 10 , wherein the future driver-required driving force computation module is configured to perform a limit process, that is based on a threshold of a change rate of the driver-required driving force, on the driver-required driving force, and compute the future driver-required driving force based on the driver-required driving force that has undergone the limit process.

12. The battery voltage control device according to claim 1 , further comprising:
a driving state forecast module configured to forecast that an acceleration to pass will be performed by a lane change based on the environment information,
wherein the step-up control module is further configured to control step-up by the step-up module based on a voltage margin according to a vehicle speed or a driver-required driving force based on a determination that the acceleration to pass is forecast to be performed.

13. The battery voltage control device according to claim 12 , wherein the step-up control module is further configured to set a value of the voltage margin to be a high value with a decrease in the vehicle speed.

14. The battery voltage control device according to claim 12 , wherein the step-up control module is further configured to set a value of the voltage margin to be a high value with a decrease in the required driving force.

15. The battery voltage control device according to claim 12 , wherein the step-up control module is further configured to set the voltage margin based on a voltage margin map on which the voltage margin is prescribed according to the vehicle speed or the required driving force.

16. The battery voltage control device according to claim 15 , wherein the voltage margin map prescribes the voltage margin based on the vehicle speed or the required driving force according to a driving mode.

17. A battery voltage control method comprising:
acquiring a driving state of a vehicle;
monitoring an outside of the vehicle and acquiring environment information of the outside of the vehicle; and
controlling step-up of a battery voltage by a step-up converter based on the acquired environment information of the outside of the vehicle.

18. The battery voltage control method according to claim 17 , further comprising:
forecasting a driving state including starting or stopping of the vehicle based on the environment information of the outside of the vehicle, wherein, in the controlling of the step-up, the step-up of the battery voltage by the step-up converter is controlled based on the forecast driving state.

19. The battery voltage control method according to claim 17 , further comprising:
acquiring a travel mode that relates to an output characteristic of a driving motor; and
acquiring an accelerator opening degree,
wherein, in the controlling of the step-up, a target step-up voltage of step-up of a battery voltage to be applied to the driving motor is controlled based on the travel mode and the accelerator opening degree.

20. The battery voltage control method according to claim 17 , further comprising:
forecasting that an acceleration for passing will be performed by a lane change based on the environment information of the outside of the vehicle; and
computing a voltage margin according to a vehicle speed of a driver-required driving force based on a determination that the acceleration for passing is forecast, wherein, in the step of controlling the step-up, step-up of a battery voltage by a step-up converter is controlled based on the computed voltage margin.

21. A battery voltage control device, comprising:
a step-up module configured to step-up a voltage of a battery and then apply the voltage to a driving motor;
a step-up control module configured to control s

Assignees

• Fuji Heavy Ind Ltd
• Subaru Corp

Inventors

• Morita Tomohiro

Classifications

• B60L2240/12

  Speed · CPC title

• B60L2260/50

  by future state prediction · CPC title

• Y02T90/16

  Information or communication technologies improving the operation of electric vehicles · CPC title

• B60L2210/12

  Buck converters · CPC title

• B60L2240/527

  Voltage · CPC title