Multi-Source Battery Charging via Closed-Loop Servo Control

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Solution Overview

Problem

Existing battery charging systems for portable electronic devices often struggle to efficiently charge batteries using multiple power sources simultaneously, leading to slower charging or potential battery discharge when the chosen power source is insufficient to provide all necessary power.

Innovation Solution

A closed-loop servo system utilizing multiple power converters and a microprocessor to prioritize and coordinate power sources, adjusting voltage targets based on sensor measurements and a predetermined charging profile to ensure efficient charging from multiple power sources.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If a single power source is selected to charge the battery, then the charging system is simple to control, but the charging speed is limited by the capacity of that single power source

Engineering Contradiction:
Improvecharging speedVSAvoidcontrol system complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The charging system is segmented into multiple independent power converters (first power converter, second power converter, etc.), each capable of accepting power from different power sources and contributing to battery charging independently. This segmentation allows parallel charging operations, increasing overall charging speed without requiring a single complex controller to manage all power flow decisions.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

A closed-loop feedback control mechanism is implemented where the controller continuously monitors the charging state, power source availability, and battery status, then dynamically adjusts the operation of individual power converters. This feedback system automatically optimizes power distribution among multiple converters, enabling high-speed charging while maintaining manageable control complexity through decentralized decision-making.

Inventive Principle:
Principle #23Feedback

2Power

If multiple power converters operate simultaneously without coordination, then charging capacity is maximized, but power converters may conflict over control of the shared voltage rail

Engineering Contradiction:
Improvetotal charging capacityVSAvoidsystem stability
Core Design Contradiction:
PowerVSReliability

Solution Approach 1:

Power converters are assigned predetermined priority levels and target voltage values before operation begins. The controller pre-configures each converter's operating parameters based on its priority assignment, establishing a hierarchical control structure that prevents conflicts before they occur. This preliminary arrangement ensures that when multiple converters operate simultaneously on a shared voltage rail, they do so in a coordinated manner that maximizes power capacity while maintaining system stability.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP3417526B1Systems and methods for simultaneously charging a battery with multiple power sources
Publication Date: 2021.12.01 APPLE INC
  • EP3417526B1 patent drawingFigure 1
  • EP3417526B1 patent drawingFigure 2
  • EP3417526B1 patent drawingFigure 3

AI summary

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.