First, a power receiving apparatus RX is detected (S100). Subsequently, a pre digital ping is sent according to a first method (S112). Upon reception of an unique signal defined for the first method from the power receiving apparatus RX (YES in S114), tentative judgment is made that the power receiving apparatus RX supports the first method, and the flow transits to a final judgment operation (S120). When such an unique signal has not been received (NO in S114), tentative judgment is made that the power receiving apparatus RX supports a second method, and the flow transits to a final judgment operation (S130).