A wireless power transmission device radiates electromagnetic waves through a transmission antenna and generates multiple sensed signals by using multiple foreign object detection (FOD) coils for detecting metallic foreign object to sense the electromagnetic waves. Each FOD coil has three coil units connected in series to and spaced apart from one another. The radiation pattern of the transmission antenna overlaps a sensing range of the FOD coils. A controller of the wireless power transmission device determines if any metallic foreign object enters the radiation range of the transmission antenna according to a reference voltage signal and sensed signals of the cells, and stops the generation of electromagnetic waves when determining entry of metallic foreign object into the radiation range to avoid the metallic foreign object to be heated by the electromagnetic waves.

Applied Country	Category	專利狀態	證書號	專利權期間	研究成果公告日期
TW	Elecric vehicle technology	獲證	CN107306054B	2020/11/10~2036/04/24
US	Elecric vehicle technology	獲證	CN107306054B	2020/11/10~2036/04/24
CN	Elecric vehicle technology	獲證	CN107306054B	2020/11/10~2036/04/24