Electrified vehicle control using battery state of charge and power capability strategy

Patent metadata

Field	Value
Publication number	US-11814030-B2
Application number	US-202016936054-A
Country	US
Kind code	B2
Filing date	Jul 22, 2020
Priority date	Jul 22, 2020
Publication date	Nov 14, 2023
Grant date	Nov 14, 2023

Abstract

A vehicle and control method include a traction battery, a temperature sensor, current sensor, and voltage sensor associated with the traction battery, an electric machine powered by the traction battery to provide propulsive power to the vehicle, and a controller configured to control at least one of the electric machine and the traction battery in response to a battery state of charge (SOC) estimated using a battery model having parameters including a first resistance in series with a second resistance and a capacitance in parallel to the second resistance. The battery model parameters are adjusted during vehicle operation using a Kalman filter and reinitialized to new values in response to a vehicle key-on, in response to a change in the battery current exceeding a corresponding threshold, and/or in response to any of the parameter values crossing an associated limit.

First claim

What is claimed is:

1. A vehicle comprising:
a traction battery having a plurality of cells;
a temperature sensor configured to measure battery temperature of the traction battery;
a current sensor configured to measure battery current flow to and from the traction battery;
a voltage sensor configured to measure output terminal voltage of the traction battery;
an electric machine powered by the traction battery and configured to provide propulsive power to the vehicle; and
a controller configured to control at least one of the electric machine and the traction battery in response to an estimated battery power capability based on a battery model having a plurality of model parameters reinitialized in response to at least one of the plurality of model parameters having a value exceeding a corresponding limit for the at least one model parameter.

2. The vehicle of claim 1 wherein the controller is further configured to reinitialize the plurality of model parameters in response to a change in battery current exceeding a corresponding threshold.

3. The vehicle of claim 1 wherein the plurality of model parameters comprises a first resistance, a second resistance, and a capacitance of the battery model, wherein the first resistance is in series with the second resistance and the capacitance is in parallel with the second resistance.

4. The vehicle of claim 3 wherein the controller is further configured to adjust the first resistance, the second resistance, and the capacitance during operation of the vehicle using a Kalman filter.

5. The vehicle of claim 4 wherein the controller controls at least one of the electric machine and the traction battery in response to a state of charge (SOC) of the traction battery, the SOC based on the plurality of model parameters, the battery temperature, the battery current, and the battery terminal voltage.

6. The vehicle of claim 3 wherein each of the plurality of model parameters is reinitialized to a previously stored value.

7. The vehicle of claim 3 further comprising a transceiver configured to wirelessly communicate vehicle data to a cloud server, wherein each of the plurality of model parameters is reinitialized to a value received from the cloud server.

8. The vehicle of claim 1 further comprising an internal combustion engine coupled to the electric machine.

9. A vehicle comprising:
a traction battery;
a temperature sensor configured to measure battery temperature of the traction battery;
a current senor configured to measure battery current flow to and from the traction battery;
a voltage sensor configured to measure output terminal voltage of the traction battery;
an electric machine powered by the traction battery and configured to provide propulsive power to the vehicle; and
a controller configured to control at least one of the electric machine and the traction battery in response to a battery state of charge (SOC) estimated using a battery model including a first resistance in series with a second resistance and a capacitance in parallel to the second resistance, wherein the first resistance, second resistance, and the capacitance are initialized to corresponding values in response to at least one of the values crossing a corresponding battery model parameter value limit and a change in the battery current exceeding a corresponding threshold.

10. The vehicle of claim 9 wherein the first resistance, the second resistance, and the capacitance values are adjusted during operation of the vehicle based on a Kalman filter.

11. The vehicle of claim 10 wherein values for the first resistance, the second resistance, and the capacitance values are received wirelessly by the controller from a cloud server.

12. The vehicle of claim 9 further comprising an internal combustion engine.

13. The vehicle of claim 12 wherein the controller is further configured to determine a battery power capability based on the first resistance, the second resistance, and the capacitance.

14. The vehicle of claim 13 wherein the first resistance, the second resistance, and the capacitance are determined as a function of the battery temperature, the battery current, and age of the traction battery.

15. A method for controlling an electrified vehicle, comprising, by a controller:
initializing traction battery model parameters for a first resistance, a second resistance, and a capacitance in response to a vehicle key-on;
controlling at least one of an electric machine and the traction battery in response to a battery state of charge (SOC) and a battery power capability estimated using the battery model including the first resistance in series with the second resistance and the capacitance in parallel to the second resistance, wherein the first resistance, the second resistance, and the capacitance are adjusted during operation of the vehicle using a Kalman filter, and wherein the first resistance, the second resistance, and the capacitance are re-initialized to associated values in response to a change in the battery current exceeding a corresponding current threshold, and in response to at least one of the first resistance, the second resistance, and the capacitance exceeding respective first resistance, second resistance, and capacitance limit thresholds.

16. The method of claim 15 wherein at least one of the SOC and the battery power capability are determined as a function of temperature of the traction battery.

17. The method of claim 16 wherein at least one of the SOC and the battery power capability are determined as a function of age of the traction battery.

18. The method of claim 17 wherein at least one of the SOC and the battery power capability are determined as a function of traction battery current.

19. The method of claim 18 further comprising wirelessly receiving values to initialize the first resistance, the second resistance, and the capacitance from a cloud server.

Assignees

• Ford Global Tech Llc

Inventors

• Vuylsteke Gabrielle
• Araujo Xavier Marcelo

Classifications

• B60W20/00 Primary

  Control systems specially adapted for hybrid vehicles {(hybrid vehicle design, B60K6/00; electric vehicles B60L)} · CPC title

• B60W10/06

  including control of combustion engines · CPC title

• B60W10/08

  including control of electric propulsion units, e.g. motors or generators · CPC title

• B60W10/24

  including control of energy storage means · CPC title

• B60W2510/244

  Charge state · CPC title