POWER SUPPLY APPARATUS AND ELECTRONIC DEVICE, AND CONTROL METHOD THEREOF, AND WIRELESS POWER TRANSMISSION SYSTEM

According to the present invention, the communication mode can be prevented from changing when re-authentication is performed. To achieve this, a power supply apparatus that wirelessly supplies power to an electronic device, comprises a communicating unit that contactlessly transmits power and transmits/receives information, a holding unit that holds, when authentication is first performed with an electronic device via the communicating unit, information indicating a communication mode when communication is established with the electronic device, and a controlling unit that controls the communicating unit so as to perform communication in a communication mode based on the information held in the holding unit, when a second authentication is performed with the electronic device via the communicating unit.