Patent ID: 8552596

Claim:
A power transmitting apparatus for forming a pair with a power receiving apparatus, the power receiving apparatus including secondary side coupling electrodes and a high-frequency voltage load circuit connected to the secondary side coupling electrodes and having a resonant circuit formed of the secondary side coupling electrodes and the high-frequency voltage load circuit, the power transmitting apparatus comprising: primary side coupling electrodes couplable to the secondary side coupling electrodes; a high-frequency voltage generator circuit adapted to apply a high-frequency voltage across the primary side coupling electrodes; a driving power supply circuit adapted to supply driving power to the high-frequency voltage generator circuit, said driving power supply circuit including a driving power supply switching unit adapted to supply either a constant current or a constant voltage to the high-frequency voltage generator circuit; a voltage detection unit adapted to detect a voltage supplied to the high-frequency voltage generator circuit; and a control unit adapted to detect a frequency at which the voltage supplied to the high-frequency voltage generator circuit becomes a maximal voltage for a change in frequency of a voltage generated by the high-frequency voltage generator circuit in a state in which the constant current is supplied, to set the frequency corresponding to the maximal voltage as the frequency of the voltage generated by the high-frequency voltage generator circuit, and to perform switching so as to supply the constant voltage.