FOREIGN MATTER DETECTION DEVICE AND METHOD FOR NON-CONTACT POWER SUPPLY DEVICE

PROBLEM TO BE SOLVED: To provide a foreign matter detection device and method for a non-contact power supply device capable of reducing an induction voltage generated in a coil for foreign matter detection, and therefore achieving the increase of the sensitivity of foreign matter detection for detecting the presence/absence of a conductive foreign matter and the reduction of erroneous detection.SOLUTION: The foreign matter detection device includes: a detection coil 12 positioned between a power transmission coil 3 and a power reception coil 4; and a detection unit 14 for detecting an induction voltage V generated in the detection coil 12, and for detecting the presence/absence of a conductive foreign matter positioned between the power transmission coil 3 and the power reception coil 4 from this. The detection coil 12 is configured of a consecutive conductive wire 13 in which two loop parts 12a are wound mutually in reverse directions. The area and the number of windings of each loop part 12a or a direction connecting the centroids of the two loop parts 12a are set such that the induction voltage V(that is, a reference voltage V0) generated in the detection coil 12 when there does not exist any conductive foreign matter becomes 0 or minimum. 【課題】異物検出用のコイルに発生する誘導電圧を低減することができ、これにより導電性異物の有無を検出する異物検出の感度を高め、誤検出を低減することができる非接触給電装置用の異物検出装置と方法を提供する。【解決手段】送電コイル３と受電コイル４との間に位置する検出コイル１２と、検出コイル１２に発生する誘導電圧Ｖを検出し、これから送電コイル３と受電コイル４との間に位置する導電性異物の有無を検出する検出ユニット１４とを備える。検出コイル１２は、２つのループ部１２ａが互い逆方向に巻かれた連続した導電線１３からなる。各ループ部１２ａの面積、巻き数、又は２つのループ部１２ａの図心を結ぶ方向が、導電性異物が存在しないときに検出コイル１２に発生する誘導電圧Ｖ（すなわち基準電圧Ｖ０）が０又は最小になるように設定されている。【選択図】図４