METHOD FOR ESTIMATING VEHICLE BATTERY PARAMETERS

• US 20130241565A1
• Filed: 03/19/2012
• Published: 09/19/2013
• Est. Priority Date: 03/19/2012
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Gibbs, James C.
• Granted Patent: US 9,522,599 B2
• Time in Patent Office: Days
• US Class Current: 324/433
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 2260/44 by parameter estimation
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 58/16 responding to battery ageing, e.g. to the number of charging cycles or the state of health [SoH]
• CPC Class Codes: B60L 58/20 having different nominal voltages
• CPC Class Codes: B60L 7/18 Controlling the braking effect B60L7/12, B60L7/14, B60L7/16 take precedence
• CPC Class Codes: G01R 31/382 Arrangements for monitoring battery or accumulator variables, e.g. SoC
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors

Abstract

A method and system for accurately estimating one or more vehicle battery parameters, such as state-of-charge (SOC). In an exemplary embodiment, a battery control module gathers standard battery readings for estimating SOC at a relatively slow sampling rate. The battery control module receives adjustment data from one or more control modules located around the vehicle, where the control modules gather readings at faster sampling rates and then provide the information to the slower battery control module. The adjustment data from the faster control modules is representative of energy consumption and/or generation events that occur in between the readings taken by the battery control module at the slower sampling rate, and enable the method to make a more accurate and complete estimate of SOC.

Claims

1. A method for estimating a vehicle battery parameter, comprising the steps of:

(a) determining an initial value for the vehicle battery parameter being estimated, the initial value is based on data gathered at a first sampling rate;

(b) determining an adjustment factor for the vehicle battery parameter being estimated, the adjustment factor is based on data gathered at a second sampling rate that is faster than the first sampling rate; and

(c) modifying the initial value with the adjustment factor to determine an overall value for the vehicle battery parameter being estimated, wherein the overall value takes into account changes to the vehicle battery parameter that are represented in the data gathered at the second sampling rate but are not represented in the data gathered at the first sampling rate.

2. The method of claim 1, wherein the vehicle battery parameter is a state-of-charge (SOC), and step (a) further comprises determining an initial value for the SOC, step (b) further comprises determining an adjustment factor for the SOC, and step (c) further comprises modifying the initial value with the adjustment factor to determine an overall value for the SOC.

3. The method of claim 2, wherein step (a) further comprises determining the initial value for the SOC by using battery voltage and battery current readings gathered at the first sampling rate.

4. The method of claim 2, wherein step (b) further comprises determining the adjustment factor for the SOC by using adjustment data gathered at the second sampling rate.

5. The method of claim 4, wherein step (b) further comprises using a battery control module to determine the adjustment factor for the SOC, the adjustment factor is determined by receiving the adjustment data from a separate control module at the battery control module and using the adjustment data from the separate control module to determine the adjustment factor.

6. The method of claim 5, wherein the separate control module is a suspension control module and the adjustment data represents energy that has been consumed by actuators under the control of the suspension control module.

7. The method of claim 5, wherein the separate control module is a brake control module and the adjustment data represents energy that has been consumed or generated by devices under the control of the brake control module.

8. The method of claim 4, wherein step (b) further comprises determining the adjustment factor for the SOC by using at least one of the following pieces of adjustment data:

the amount of energy of an energy consumption event or the duration of an energy consumption event.

9. The method of claim 4, wherein step (b) further comprises determining the adjustment factor for the SOC by gathering adjustment data regarding energy consumption by a plurality of devices that are controlled by a single control module.

10. The method of claim 4, wherein step (b) further comprises determining the adjustment factor for the SOC by gathering adjustment data regarding energy consumption by a plurality of devices that are controlled by a plurality of control modules.

11. The method of claim 4, wherein step (b) further comprises determining the adjustment factor for the SOC by using adjustment data that is gathered at the second sampling rate and is provided in a cumulative message that is sent at the first sampling rate.

12. The method of claim 2, wherein step (c) further comprises adding the adjustment factor for the SOC to the initial value for the SOC to determine the overall value for the SOC, the overall value is less than the initial value during energy consumption events and the overall value is greater than the initial value during energy generation events.

13. A method for estimating a state-of-charge (SOC) for a vehicle battery, comprising the steps of:

(a) determining an initial value for the SOC, the initial value is based on data gathered by a first device;

(b) determining an adjustment factor for the SOC, the adjustment factor is based on data gathered by a second device that gathers data faster than the first device; and

(c) modifying the initial value with the adjustment factor to determine an overall value for the SOC, wherein the overall value takes into account changes to the SOC that are represented in the data gathered by the second device but are not represented in the data gathered by the first device.

14. The method of claim 13, wherein step (a) further comprises determining the initial value for the SOC by using battery voltage and battery current readings gathered by the first device.

15. The method of claim 13, wherein step (b) further comprises determining the adjustment factor for the SOC by using adjustment data gathered by the second device.

16. The method of claim 13, wherein step (b) further comprises using a battery control module to determine the adjustment factor for the SOC, the adjustment factor is determined by receiving adjustment data from a separate control module at the battery control module and using the adjustment data from the separate control module to determine the adjustment factor.

17. The method of claim 16, wherein the separate control module is a suspension control module and the adjustment data represents energy that has been consumed by actuators under the control of the suspension control module.

18. The method of claim 16, wherein the separate control module is a brake control module and the adjustment data represents energy that has been consumed or generated by devices under the control of the brake control module.

19. The method of claim 16, wherein step (b) further comprises determining the adjustment factor for the SOC by using at least one of the following pieces of adjustment data:

the amount of energy of an energy consumption event or the duration of an energy consumption event.

20. The method of claim 13, wherein step (c) further comprises adding the adjustment factor for the SOC to the initial value for the SOC to determine the overall value for the SOC, the overall value is less than the initial value during energy consumption events and the overall value is greater than the initial value during energy generation events.