Parallel Charger Handover in Wireless Power Transfer CC-CV Charging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wireless charging systems, particularly those using buck chargers, have low efficiency compared to other chargers like switched capacitor chargers, necessitating a method to enhance battery charging efficiency through a wireless power transfer system.
Innovation Solution
A method involving a buck charger and a switched capacitor charger connected in parallel, where the buck charger is enabled during constant current mode and the switched capacitor charger during constant voltage mode, with both chargers enabled during transitions to improve performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a buck charger is used for wireless charging, then the system is simple and reliable, but the charging efficiency is low
Solution Approach 1:
The charging system is segmented into two separate charger circuits: a buck charger and a switched capacitor charger. Each charger is optimized for specific charging phases, with the buck charger handling constant current mode and the switched capacitor charger handling constant voltage mode. This segmentation allows each component to operate at optimal efficiency in its designated phase while maintaining system reliability.
Solution Approach 2:
The system dynamically switches between different charger circuits based on charging phase requirements. The controller activates the appropriate charger (buck or switched capacitor) depending on whether constant current or constant voltage mode is needed, enabling the system to adapt its charging approach for optimal efficiency throughout the charging process.
2Device complexity
If only one charger circuit is used, then the device complexity is low, but the charging performance across different phases is suboptimal
Solution Approach 1:
The charging function is divided into two specialized circuits: buck charger for constant current phase and switched capacitor charger for constant voltage phase. This segmentation enables each circuit to be optimized for its specific function, improving overall charging performance while keeping individual circuit designs relatively simple.
Solution Approach 2:
The wireless charging system is designed with multi-functionality by incorporating two charger circuits that can be selectively activated. The system universally handles both constant current and constant voltage charging phases using appropriate charger circuits, making the system capable of optimal performance across all charging conditions.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration enhances the efficiency of the wireless power transfer system by enabling simultaneous charging during transitions and optimizing charging phases, leading to improved battery charging performance.
Implementation Method 1
The primary side transmitter is configured to generate an alternating current on the primary side coil to form a varying magnetic field, thereby generating a voltage in the secondary side coil
Implementation Method 2
The primary side transmitter is magnetically coupled to the secondary side receiver through a magnetic coupling
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A method includes charging a battery (113) through a first charger (218) and a second charger (219) connected in parallel, during a first transition from a constant current charging phase to a constant voltage charging phase, enabling the second charger (219) at a first time instant and disabling the first charger (218) at a second time instant, the second time instant being after the first time instant, and during the constant voltage charging phase, enabling the first charger (218) at a third time instant upon detecting that a current flowing through the battery (113) is less than a predetermined current threshold and disabling the second charger (219) at a fourth time instant, the fourth time instant being after the third time instant, wherein the first charger (218) and the second charger (219) are configured to charge the battery (113) simultaneously between the first time instant and the second time instant, and between the third time instant and the fourth time instant.