A foreign object detector includes: an oscillator circuit 100 having a coil 110 and resonant capacitors Cx, Cy, the oscillator circuit 100 being configured to output a voltage which includes an AC component and a DC component, the AC component having a pos...

In a first power transmission period, a power transmission device holds, in a memory, a value indicating a frequency f0 corresponding to an actual voltage value that matches a requested voltage value, then causes first AC power to be transmitted by using t...

A metal foreign object detection device (7) for a contactless power supplying system comprises an antenna coil (AT2), an oscillation circuit (7a) that applies high-frequency current to the antenna coil (AT2), and a detection circuit (7b) that detects a cha...