IP Library › Granted Patent US 10,254,345

Granted Patent B2

US 10,254,345 · App. 15/541,503 · Granted Apr 9, 2019

Battery state-of-charge estimation apparatus and state-of-charge estimation method

Inventors: Hideaki Tani (Tokyo, JP); Satoshi Wachi (Tokyo, JP); Hiroyuki Saito (Tokyo, JP); Hiroto Nishiguchi (Tokyo, JP); Keisuke Ogasawara (Tokyo, JP)

Assignee: Mitsubishi Electric Corporation

G01R31/361 G01R31/36 H01M10/44 H01M10/443 H01M10/448 H01M10/48 H01M10/486 H02J7/0047 B60L11/1861 B60W2510/244 H01M2220/20 H02J2007/005

View Patent ↗

Loading inventors, assignments & file history…

Monitor This Case

Get email alerts when status or documents change.

Order Certified Copies

Most orders are placed with the USPTO same day — all within 24 business hours.

Order via The Patent Place →

Pre-filled with this patent's details

Quick Facts

Patent No.: US 10,254,345
App. No.: 15/541,503
Granted: Apr 9, 2019
Kind: B2

External Links

USPTO Patent Center↗ Full Patent PDF↗

Abstract

Final state-of-charge calculation means is provided which calculates a final state-of-charge of the battery according to state-of-charge estimate values by electric current integration mode state-of-charge estimation means and equivalent circuit model mode state-of-charge estimation means. The final state-of-charge calculation means performs, when a difference between the state-of-charge estimate value by the electric current integration mode state-of-charge estimation means and the state-of-charge estimate value by the equivalent circuit model mode state-of-charge estimation means becomes less than or equal to the state-of-charge difference threshold value, switching of the final state-of-charge from the state-of-charge estimate value by the electric current integration mode state-of-charge estimation means to the state-of-charge estimate value by the equivalent circuit model mode state-of-charge estimation means.

Claims (75)

1. A battery state-of-charge estimation apparatus comprising at least one microprocessor comprising:

an electric current integration mode state-of-charge calculator to calculate a first state-of-charge estimate value of a battery according to an electric current integration mode;

an equivalent circuit model mode state-of-charge calculator to calculate a second state-of-charge estimate value of the battery according to an equivalent circuit model mode;

a state-of-charge difference threshold value calculator to calculate a state-of-charge difference threshold value for a difference between the first state-of-charge estimate value, and the second state-of-charge estimate value; and

a final state-of-charge calculator to calculate a final state-of-charge of the battery according to the first and the second state-of-charge estimate values, wherein

the final state-of-charge calculator performs,

when the difference between the first state-of-charge estimate value and the second state-of-charge estimate value becomes less than or equal to the state-of-charge difference threshold value,

switching of the final state-of-charge from the first state-of-charge estimate value to the second state-of-charge estimate value, and

the final state-of-charge calculator prohibits the first state-of-charge estimate value from being switched, until an initial start-up of a vehicle having the battery mounted therein is completed.

2. The battery state-of-charge estimation apparatus according to claim 1 , wherein the at least one microprocessor further comprises an electric current integration mode state-of-charge estimate error calculator to calculate, by accumulating electric current detection errors of an electric current sensor, a state-of-charge estimate error that is an error of the first state-of-charge estimate value by the electric current integration mode state-of-charge calculator, wherein

the state-of-charge difference threshold value is obtained by clipping of an upper limit of the state-of-charge estimate error.

3. The battery state-of-charge estimation apparatus according to claim 2 , wherein

the at least one microprocessor further comprises a final state-of-charge calculator, and

the final state-of-charge calculator performs,

after a condition that the difference between the first state-of-charge estimate value and the second state-of-charge estimate value is less than or equal to the state-of-charge estimate error is satisfied for a predetermined time period,

when the difference between the first state-of-charge estimate value and the second state-of-charge estimate value becomes less than or equal to the state-of-charge difference threshold value,

switching of the final state-of-charge from the first state-of-charge estimate value to the second state-of-charge estimate value.

4. The battery state-of-charge estimation apparatus according to claim 2 , wherein

the at least one microprocessor further comprises a final state-of-charge calculator, and

the final state-of-charge calculator performs,

when a condition that the difference between the first state-of-charge estimate value and the second state-of-charge estimate value is less than or equal to the state-of-charge estimate error is satisfied for a predetermined time period,

switching of the final state-of-charge from the first state-of-charge estimate value to the second state-of-charge estimate value.

5. The battery state-of-charge estimation apparatus according to claim 1 , wherein

the state-of-charge difference threshold value is calculated based on a map according to the final state-of-charge, and

the state-of-charge difference threshold value is set to be reduced as the final state-of-charge approaches an upper limit value and a lower limit value from an intermediate value.

6. The battery state-of-charge estimation apparatus according to claim 1 , wherein

the state-of-charge difference threshold value is calculated based on a map according to the final state-of-charge,

when the final state-of-charge is near an upper limit value and a temperature of the battery is high, the state-of-charge difference threshold value is set to be reduced, and

when the final state-of-charge is near a lower limit value and a temperature of the battery is low, the state-of-charge difference threshold value is set to be reduced.

7. The battery state-of-charge estimation apparatus according to claim 1 , wherein

the state-of-charge difference threshold value calculator includes a battery state determiner to determine whether or not the battery is under a stable condition, and

the state-of-charge difference threshold value is set to be reduced in a case where the battery is not under the stable condition, as compared to a case where the battery is under the stable condition.

8. The battery state-of-charge estimation apparatus according to claim 1 , wherein

the final state-of-charge calculator

constantly sets, as the final state-of-charge, the second state-of-charge estimate value according to the equivalent circuit model mode when a key-off time period of the vehicle is less than or equal to a predetermined time period.

9. A battery state-of-charge estimation apparatus comprising at least one microprocessor comprising:

an electric current integration mode state-of-charge calculator for calculating a state-of-charge estimate value of a battery according to an electric current integration mode;

an equivalent circuit model mode state-of-charge calculator for calculating a state-of-charge estimate value of the battery according to an equivalent circuit model mode;

a state-of-charge difference threshold value calculator for calculating a state-of-charge difference threshold value for a difference between the state-of-charge estimate value by the electric current integration mode state-of-charge calculator, and the state-of-charge estimate value by the equivalent circuit model mode state-of-charge calculator; and

a final state-of-charge calculator for calculating a final state-of-charge of the battery according to the state-of-charge estimate values by the electric current integration mode state-of-charge calculator and the equivalent circuit model mode state-of-charge calculator, wherein

the final state-of-charge calculator preforms,

when the difference between the state-of-charge estimate value by the electric current integration mode state-of-charge calculator and the state-of-charge estimate value by the equivalent circuit model mode state-of-charge calculator becomes less than or equal to the state-of-charge difference threshold value,

switching of the final state-of-charge from the state-of-charge estimate value by the electric current integration mode state-of-charge calculator to the state-of-charge estimate value by the equivalent circuit model mode state-of-charge calculator; and

the final state-of-charge calculator includes

a state-of-charge estimate value stepwise changer to change stepwise between the state-of-charge estimate value by the electric current integration mode state-of-charge calculator and the state-of-charge estimate value by the equivalent circuit model mode state-of-charge calculator when the final state-of-charge is switched.

10. A battery state-of-charge estimation apparatus comprising at least one microprocessor comprising:

an electric current integration mode state-of-charge calculator for calculating a state-of-charge estimate value of a battery according to an electric current integration mode;

an equivalent circuit model mode state-of-charge calculator for calculating a state-of-charge estimate value of the battery according to an equivalent circuit model mode;

an equivalent circuit model failure diagnosis tester to diagnose the equivalent circuit model mode state-of-charge calculator, wherein

the final state-of-charge calculator performs,

the final state-of-charge calculator constantly sets, as the final state-of-charge, the state-of-charge estimate value according to the electric current integration mode state-of-charge calculator when the equivalent circuit model failure diagnosis tester detects a failure of the equivalent circuit model mode state-of-charge calculator.

11. A battery state-of-charge estimation method comprising:

a first step of calculating a first state-of-charge estimate value of a battery according to an electric current integration mode;

a second step of calculating a second state-of-charge estimate value of the battery according to an equivalent circuit model mode;

a third step of calculating a state-of-charge difference threshold value for a difference between the first state-of-charge estimate value and the second state-of-charge estimate value;

and

a fourth step of calculating a final state-of-charge of the battery according to the first state-of-charge estimate value and the second state-of-charge estimate value, wherein

in the fourth step,

when a difference between the first state-of-charge estimate value and the second state-of-charge estimate value becomes less than or equal to the state-of-charge difference threshold value, the final state-of-charge is switched from the first state-of-charge estimate value to the second state-of-charge estimate value, and

the first state-of-charge estimate value is prohibited from being switched to the second state-of-charge estimate value, until an initial start-up of a vehicle having the battery mounted therein is completed.

12. The battery state-of-charge estimation method according to claim 11 , comprising a fifth step of calculating, by accumulating electric current detection errors of an electric current sensor, a state-of-charge estimate error that is an error of the first state-of-charge estimate value, wherein

the state-of-charge difference threshold value is obtained by clipping of an upper limit of the state-of-charge estimate error.

13. The battery state-of-charge estimation method according to claim 11 , wherein

in the fourth step,

when the difference between the first state-of-charge estimate value and the second state-of-charge estimate value becomes less than or equal to the state-of-charge difference threshold value,

the final state-of-charge is switched from the first state-of-charge estimate value to the second state-of-charge estimate value.

14. The battery state-of-charge estimation method according to claim 11 , wherein

in the fourth step,

the final state-of-charge is switched from the first state-of-charge estimate value to the second state-of-charge estimate value.

Assignments (1)

ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jul 5, 2017

From: TANI, HIDEAKI; WACHI, SATOSHI; SAITO, HIROYUKI; NISHIGUCHI, HIROTO; OGASAWARA, KEISUKE

To: MITSUBISHI ELECTRIC CORPORATION

Reel/Frame 042899/0862 →

Continuity (1)

Related Publication 20170350943A1 · Dec 7, 2017