FOREIGN OBJECT DETECTION DEVICE, POWER TRANSMISSION DEVICE, POWER RECEPTION DEVICE, AND POWER TRANSFER SYSTEM

To accurately detect the existence of a foreign object that may exist in a wireless power transfer device.SOLUTION: A foreign object detection device 20 includes: a plurality of coils 242 which are arranged adjacent to each other on an arrangement surface and generate a vibration signal in response to being excited; and a detector 26 connected to the coils 242 to detect the existence of a foreign object based on a responding signal output from each of the coils 242. The arrangement surface has a first region in which the coils are grouped into a plurality of first coil groups each containing at least two coils 242. The detector 26 detects the existence of a foreign object based on the vibration signal output from each of the coils 242 contained in the first coil groups. The first coil groups contain mutually different combinations of coils 242 contained in the first coils, and one coil 242 contained in at least one first coil group is also contained in another first coil group.SELECTED DRAWING: Figure 1 【課題】ワイヤレスで電力を伝送する装置に存在しうる異物の有無を正確に検出する。【解決手段】異物検出装置２０は、配置面に相互に隣接して配列され、励磁されたことに応答して振動信号を発生する複数のコイル２４２と、複数のコイル２４２に接続され、各コイル２４２の応答信号から、異物の有無を検出する検出部２６とを備える。配置面は、少なくとも２つのコイル２４２を含む複数の第１コイル組に区分けする第１領域を有する。検出部２６は、複数の第１コイル組を構成するコイル２４２それぞれの振動信号に基づき異物の有無を検出する。第１コイル組は、各第１コイル組を構成するコイル２４２の組み合わせは異なっており、少なくとも１つの第１コイル組を構成する１つのコイル２４２と他の１つの第１コイル組を構成する１つのコイル２４２とが共通している。【選択図】図１