| 摘要 |
PROBLEM TO BE SOLVED: To provide a non-contact power-feeding device which, even when a coupling coefficient between a primary side coil and a secondary side coil changes, can perform power transmission between the two coils with maximum efficiency at the coupling coefficient.SOLUTION: A secondary side coil short-circuit means 23 for short-circuiting between opposite ends of a secondary side coil 21 on a power-receiving device 2 side is provided, an inductance Lat a short-circuiting time of the secondary coil 21 is measured, and a coupling coefficient k is calculated. Then, control is exerted so that a power transmission efficiency &eegr; in a non-contact power-feeding unit 3 is at maximum by appropriately selecting the duty of a power converter 25 provided in front of a load 4 in accordance with the coupling coefficient k and a resistance value Rof the load 4. |
