Methods for determining the charge state and/or the power capacity of a charge store

• US 20040032264A1
• Filed: 06/23/2003
• Published: 02/19/2004
• Est. Priority Date: 06/29/2001
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Schoch, Eberhard
• Granted Patent: US 6,876,175 B2
• Time in Patent Office: Days
• US Class Current: 324/426
• CPC Class Codes: G01R 31/379 for lead-acid batteries
• CPC Class Codes: G01R 31/3828 using current integration

Abstract

Methods are described for determining the state of charge and/or the operability of a charge accumulator using estimates, the information, which is obtained at at least two different operating points or operating conditions of the energy accumulator, being taken into account in the estimates. The estimates are carried out with regard to an instantaneous and/or future state of charge and/or an instantaneous and/or future operability of the charge accumulator. Different methods are executed, depending on the operating point or operating condition. The methods are usually run in a processor of a control unit.

Claims

1. A method for determining the state of charge and/or the operability of a charge accumulator using estimates,

wherein information obtained at at least two different operating points of the energy accumulator is taken into account in the estimates.

2. The method for determining the state of charge and/or the operability of a charge accumulator as recited in claim 1,

wherein at least two different methods are executed, in particular an open-circuit voltage method and a model-based estimation method, and the information obtained in each case is taken into account for determining the state of charge.

3. The method for determining the state of charge and/or the operability of a charge accumulator as recited in claim 1,

wherein weightable correction variables are formed from the information.

4. The method for determining the state of charge and/or the operability of a charge accumulator as recited in claim 1, 2, or 3,

wherein the estimations are carried out with regard to an instantaneous and/or future state of charge, and/or an instantaneous and/or a future operability of the charge accumulator.

5. The method for determining the state of charge and/or the operability of a charge accumulator as recited in claim 3,

wherein the estimation with regard to the future state of charge and/or the future operability of the charge accumulator are carried out by using a predictor.

6. The method for determining the state of charge and/or the operability of a charge accumulator as recited in one of the preceding claims,

wherein the two operating states are the idle state of the charge accumulator and an active state of the charge accumulator.

7. The method for determining the state of charge and/or the operability of a charge accumulator as recited in one of the preceding claims,

wherein a state estimate and a parameter estimate are implemented.

8. The method for determining the state of charge and/or the operability of a charge accumulator as recited in claim 6,

wherein an open-circuit voltage method and a model-based estimation method are used for the state estimate and the parameter estimate.

9. The method for determining the state of charge and/or the operability of a charge accumulator as recited in one of the preceding claims,

wherein mathematical models are formed which are processable in a processor taking predefinable variables into account.

11. A device for carrying out at least one method of determining the state of charge and/or the operability of a charge accumulator as recited in one of the preceding claims,

wherein the device includes at least one processor, which is in particular a component of a control unit, to which the required information is supplied.

12. The device for determining the state of charge and/or the operability of a charge accumulator as recited in claim 11,

wherein it has means for estimating the state and parameters, means for calculating the state of charge, and means for predicting the operability, which are connected to one another.

10. A method for determining the state of charge and/or the operability of a charge accumulator,

wherein state variables and parameters are determined from the following measured variables:

battery voltage, battery current, and battery temperature according to a first method A, in particular an open-circuit voltage method; and

additional state variables and parameters are determined according to a second, model-based method B and correction variables are obtained therefrom; and

the state variables are used for calculating the state of charge, and the state variables and the parameters are used for predicting the operability of the charge accumulator and for determining the predetermined battery voltage.

13. (New) A method for determining at least one of a state of charge and an operability of a charge accumulator in accordance with an estimate, comprising:

taking into account in the estimate information obtained at at least two different operating points of the charge accumulator.

14. (New) The method as recited in claim 13, further comprising:

executing at least an open-circuit voltage operation and a model-based estimation operation; and

determining the state of charge in accordance with information obtained in each of the open-circuit voltage operation and the model-based estimation operation.

15. (New) The method as recited in claim 14, further comprising:

forming a weightable correction variable from the information.

16. (New) The method as recited in claim 13, further comprising:

performing an estimation in accordance with at least one of;

at least one of an instantaneous state of charge and a future state of charge, and

at least one of an instantaneous operability of the charge accumulator and a future operability of the charge accumulator.

17. (New) The method as recited in claim 15, further comprising:

operating a predictor to perform an estimation in accordance with at least one of a future state of charge of the charge accumulator and a future operability of the charge accumulator.

18. (New) The method as recited in claim 13, wherein:

two operating states include an idle state of the charge accumulator and an active state of the charge accumulator.

19. (New) The method as recited in claim 13, further comprising:

implementing a state estimate and a parameter estimate.

20. (New) The method as recited in claim 19, wherein:

an open-circuit voltage operation and a model-based estimation operation are used for the state estimate and the parameter estimate.

21. (New) The method as recited in claim 13, further comprising:

forming a mathematical model that is processable in a processor in accordance with a predefinable variable.

22. (New) A method for determining at least one of a state of charge and an operability of a charge accumulator in accordance with an estimate, comprising:

determining a state variable and a state parameter from the following measured variables;

a battery voltage,

a battery current, and

a battery temperature according to a first operation;

determining an additional state variable and an additional sate parameter according to a second, model-based operation;

obtaining a correction variable from at least one of the state variable, the additional state variable, the state parameter, and the additional state parameter;

calculating the state of charge in accordance with at least one of the state variable and the additional state variable; and

predicting the operability of the charge accumulator and determining the battery voltage in accordance with at least one of the state variable and the additional state variable and at least one of the state parameter and the additional state parameter.

23. (New) The method as recited in claim 22, wherein:

the first operation includes an open-circuit voltage operation.

24. (New) A device for determining at least one of a state of charge and an operability of a charge accumulator in accordance with an estimate, comprising:

an arrangement for taking into account in the estimate information obtained at at least two different operating points of the charge accumulator; and

a control unit including at least one processor and to which required information is supplied.