Systems and methods for simultaneously charging a battery with multiple power sources

• US 10,666,062 B2
• Filed: 03/06/2018
• Issued: 05/26/2020
• Est. Priority Date: 03/08/2016
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Greening, Thomas C., Hasan, Kamran M.
• Primary Examiner(s): Doan, Nghia M
• Application Number:
  US15/913,634
• Publication Number:
  US 20180205252A1
• Time in Patent Office: 812 Days
• Field of Search: 320138-140, 320160-162
• CPC Class Codes: H02J 2207/20 Charging or discharging characterised by the power electronics converter
• CPC Class Codes: H02J 2207/40 adapted for charging from various sources, e.g. AC, DC or multivoltage
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/0071 with a programmable schedule

Abstract

Systems and methods for power management are disclosed herein. In one disclosed embodiment, a battery charging system includes a battery charger for simultaneously charging a battery (and/or providing power to a system load) with multiple power sources, using a closed-loop charging servo target based on measurements taken by one or more gauges. In some embodiments, the multiple power sources may be utilized simultaneously according to a charging profile that specifies, e.g., one or more battery charging parameters, as well as according to determined priority levels for one or more of the multiple power sources coupled to the battery. In some embodiments, the priority level of a given power source is not fixed; rather, the priority level for the given power source may change based upon the characteristics of the given power source. In some embodiments, the priority levels for the multiple power sources are implemented using cascaded voltage target values.

Claims

1. A battery charging controller configured to couple to a battery gauge of a battery and a plurality of power converters, so as to supply power to a terminal of the battery, wherein the controller is configured to:

assign a priority level to each of the plurality of power converters;

set a target value for each of the plurality of power converters in accordance with a feedback control loop based on a comparison between one or more profile target values of a charging profile and one or more battery metrics measured by one or more sensors; and

cause the plurality of converters to simultaneously charge the battery in accordance with their respective assigned priority levels and target values.

2. The battery charging controller of claim 1, wherein the controller is further configured to set decreasing target values for each of the plurality of power converters in decreasing order of assigned priority level.

3. The battery charging controller of claim 2, wherein the target value for a given power converter is set to the target value of the power converter having an immediately higher priority level minus a difference offset amount.

4. The battery charging controller of claim 3, wherein the difference offset amount is determined based, at least in part, on an accuracy of the given power converter and the power converter having the immediately higher priority level.

5. The battery charging controller of claim 3, wherein the difference offset amount is not fixed for each of the plurality of power converters.

6. The battery charging controller of claim 1, wherein the assigned priority level of a power converter is based, at least in part, on a characteristic of a power supply coupled to the power converter.

7. The battery charging controller of claim 1, wherein the assigned priority level of a power converter is not fixed.

8. The battery charging controller of claim 1, further comprising a charging profile selector, wherein the charging profile selector is configured to update the one or more profile target values of the charging profile based on one or more battery metrics measured by a battery gauge.

9. A method performed by a battery charging system, comprising:

assigning, by a controller of the battery charging system, a priority level to each of a plurality of power converters;

configuring the plurality of power converters to simultaneously charge a battery in accordance with their respective assigned priority levels and responsive to a feedback control loop comprising a comparison between one or more profile target values of a charging profile and one or more battery metrics measured by a battery gauge.

10. The method of claim 9, further comprising:

comparing the one or more battery metrics to the corresponding profile target values of the charging profile to determine a minimum error, and

updating a servo target based on the minimum error, in accordance with the first feedback control loop process.

11. The method of claim 9, wherein configuring the plurality of power converters further comprises:

setting a target value of the power converter having the highest assigned priority level to the value of a servo target; and

setting decreasing target values for each of the plurality of power converters in decreasing order of assigned priority level.

12. The method of claim 11, further comprising:

adjusting the assigned priority level of at least one of the plurality of power converters.

13. The method of claim 11, further comprising:

holding the servo target at a fixed value when each of the plurality of power converters is limited by at least one of;

a battery rail voltage, an input voltage of the given power converter, an input current of the given power converter, a die thermal limit, or a duty cycle of the given power converter.

14. A portable electronic device, comprising:

a battery; and

a controller configured to;

couple to a battery gauge configured to measure one or more battery metrics of the battery;

couple to a plurality of power converters configured to supply power to a terminal of the battery;

assign a priority level to each of the plurality of power converters; and

configure the plurality of power converters to simultaneously charge the battery in accordance with their respective assigned priority level and a feedback control loop based on a comparison between a charging profile and the one or more battery metrics.

15. The portable electronic device of claim 14, wherein the controller is further configured to set a target value for each of the plurality of power converters based, at least in part, on a servo target derived from the feedback control loop.

16. The portable electronic device of claim 15, wherein the controller is further configured to set decreasing target values for each of the plurality of power converters in decreasing order of assigned priority level.

17. The portable electronic device of claim 16, wherein the target value for a given power converter is set to the target value of the power converter having an immediately higher priority level minus a difference offset amount.

18. The portable electronic device of claim 17, wherein the difference offset amount is determined based, at least in part, on an accuracy of the given power converter and the power converter having the immediately higher priority level.

19. The portable electronic device of claim 14, wherein the assigned priority level of a power converter is based, at least in part, on a characteristic of a power supply coupled to the power converter.