A contactless power supply system

PROBLEM TO BE SOLVED: To provide a power supply system that hardly causes a user to concern about a positional relation between a power transmission apparatus and a power receiving apparatus, and can supply optimum power in accordance with the positional relation by only readily arranging both the apparatuses hereabout. SOLUTION: The power supply system that can supply power to the receiving apparatus from the transmission apparatus in an electrically non-contact manner comprises: a plurality of transmission-side coils CS1 to CS3 that transmit power; a plurality of transmission-side switches SS1 to SS3 that turn on/off operations of the transmission-side coils CS1 to CS3; a plurality of receiving-side coils CJ1 to CJ3 that receive power; a plurality of receiving-side switches SJ1 to SJ3 that turn on/off operations of the receiving-side coils CJ1 to CJ3; and a determination circuit 7 that outputs a signal so that the transmission-side coils CS1 to CS3 and the receiving-side coils CJ1 to CJ3 are made to operate by the optimum combination of the coils and the switches that can provide the highest power transmission efficiency. COPYRIGHT: (C)2005,JPO&NCIPI