Inductive Charging Foreign Body Detection Using Integrated Sensors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing inductive energy transmission systems for electric vehicles face safety concerns due to the potential induction of foreign bodies, such as people or animals, into strong magnetic fields, which can lead to hazards like heating and damage, especially in unattended charging scenarios or publicly accessible areas.
Innovation Solution
A device equipped with non-contact sensors and an evaluation system that detects deviations in sensor signals to identify foreign bodies within the magnetic field area, triggering warnings and deactivating the energy transfer if necessary, ensuring operational safety and reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Extent of automation
If inductive energy transmission is used to charge electric vehicles, then charging convenience and automation are improved, but safety hazards arise from foreign objects (people, animals, conductive objects) being exposed to strong magnetic fields
Solution Approach 1:
The system performs preliminary detection of the field area before initiating energy transmission. Sensors continuously monitor the space between primary and secondary coils to detect foreign objects (people, animals, conductive items) before the magnetic field is activated, preventing harmful exposure from the outset
Solution Approach 2:
The system implements continuous feedback monitoring during the charging process. Sensors detect changes in the field area in real-time, and the control unit responds by interrupting or preventing energy transmission when foreign objects are detected, ensuring ongoing safety throughout the charging operation
2Ease of operation
If multiple primary coils are used to eliminate precise alignment requirements, then ease of operation is improved, but the ability to detect foreign bodies using traditional metal detectors deteriorates
Solution Approach 1:
The system replaces traditional mechanical metal detection methods with non-contact sensors that detect foreign objects through their presence in the field area rather than through electrical properties. This substitution enables effective foreign object detection while maintaining the multi-coil configuration that provides alignment tolerance
3Ease of operation
If the field area is made publicly accessible for convenient charging, then ease of operation is improved, but safety risks from unattended operation and foreign object exposure increase
Solution Approach 1:
The system provides self-service safety monitoring by continuously autonomously detecting foreign objects in the field area and automatically controlling energy transmission. The sensors and control unit work together without human intervention to ensure safety, allowing public accessibility while maintaining reliable protection during unattended charging operations
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
Effectively detects and responds to foreign bodies in the energy transmission field, preventing potential hazards and enhancing the operational reliability and safety of inductive energy transmission systems, particularly in automatic or publicly accessible operations.
Implementation Method 1
a magnetic field of high field strength and flux density is built up in a spatial area between a stationary primary coil and a vehicle-side secondary coil
Implementation Method 2
If such objects are exposed to a strong alternating magnetic field, eddy currents are induced in them, which lead to heating that depends on the material, the duration of the introduction, the orientation to the field and the level of the field strength
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
The invention relates to a device for the inductive transfer of electric energy from a stationary unit comprising at least one primary inductance to a vehicle that is adjacent to said unit and has at least one second inductance. The stationary unit or the vehicle has a device for detecting the presence of an object in a predetermined area that covers at least the area lying between the primary inductance and the second inductance during the inductive energy transfer. The detection device has at least one contactless sensor and an evaluation unit that is connected to the sensor. At least the sensor of the detection device is integrated into or mounted on the same housing as the primary or secondary coil of the energy transfer device. The sensor can be an ultrasonic sensor, radar sensor, infra-red sensor or an electric image sensor.