Patent ID: 9124307
Filing Date: 2015-09-01
Classification: G01V,H02J,H04B

Abstract:
1. A wireless power transmission system comprising: a power transmission apparatus having a power transmission coil to wirelessly transmit electric power; a power receiving apparatus having a power receiving coil to wirelessly receive electric power from the power transmission apparatus; and a foreign-substance detector to detect a foreign substance which is present between the power transmission coil and the power receiving coil, wherein the power transmission apparatus includes: wherein the power receiving apparatus includes: wherein the foreign-substance detector acquires a first peaking frequency from the first measurement unit and a second peaking frequency from the second measurement unit, and detects the foreign substance by the use of shift amounts of the first peaking frequency and the second peaking frequency, the first peaking frequency being a frequency at which the first reflectance reaches a local minimum, the second peaking frequency being a frequency at which the second reflectance reaches a local minimum.