Contactless Power Transmission Control for Multiple Receivers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing contactless power transmission systems face challenges in properly transmitting power when multiple power receiving devices are present, as they rely on a single power transmission device corresponding to a single power receiving device, leading to inefficiencies and safety concerns due to foreign object detection limitations.
Innovation Solution
A power transmission control device that includes a controller and a load condition detection circuit, which determines the load condition on the power receiving side using threshold information received from the power receiving device, enabling proper contactless power transmission even with multiple devices, and includes a storing section to manage system information for compatibility and foreign object detection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a single power transmission device corresponds to a single power receiving device, then ID authentication is simple, but the system cannot handle multiple power receiving devices simultaneously
Solution Approach 1:
The power transmission device is designed to perform multiple functions: it can authenticate multiple different power receiving devices, detect foreign objects, and manage power transmission to multiple devices simultaneously. The controller executes different authentication processes for different device types (electronic apparatuses vs. other devices), enabling the system to handle diverse scenarios without requiring separate dedicated systems for each case.
2Reliability
If foreign object detection is not performed, then power transmission is continuous, but safety is compromised due to undetected foreign objects
Solution Approach 1:
The system performs foreign object detection during the authentication phase, before power transmission begins. By detecting foreign objects in advance through load condition analysis during the negotiation process, the system can prevent unsafe power transmission while minimizing interruptions to legitimate power transfer operations.
Solution Approach 2:
The controller continuously monitors load conditions during authentication and power transmission, comparing detected values against threshold information from the power receiving device. This feedback mechanism allows the system to detect foreign objects and adjust or terminate power transmission accordingly, ensuring safety while maintaining efficiency for legitimate operations.
3Measurement precision
If threshold information is not transmitted from the power receiving device, then communication is simpler, but load condition determination becomes inaccurate
Solution Approach 1:
The power receiving device provides its own threshold information to the power transmission device, enabling the transmitter to accurately determine load conditions. Each power receiving device contains pre-stored threshold values specific to its characteristics, and it autonomously transmits this information during authentication, eliminating the need for the transmitter to have extensive device-specific databases.
4Reliability
If system information is not collated, then authentication is faster, but compatibility between different devices cannot be ensured
Solution Approach 1:
The system performs selective collation of system information based on device type. For electronic apparatuses, full system information collation is performed to ensure compatibility. For other devices, a simplified authentication process is used. This partial approach ensures compatibility where needed while minimizing authentication time for standard cases.
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 solution ensures safe and efficient contactless power transmission by accurately determining load conditions and detecting foreign objects, allowing for various combinations of primary and secondary coils and reducing the complexity of managing multiple secondary coils on the primary side.
Implementation Method 1
power is transmitted from the power transmission device to a power receiving device by electromagnetically coupling a primary coil and a secondary coil
Data Source
AI summary
A power transmission control device included in a contactless power transmission system in which power is transmitted from a power transmission device to a power receiving device by electromagnetically coupling a primary coil and a secondary coil and the power is supplied to a load of the power receiving device, includes a controller controlling the power transmission control device, and a load condition detection circuit detecting a load condition on a power receiving side. The controller determines the load condition on the power receiving side based on threshold information received from the power receiving device and load condition detection information from the load condition detection circuit.