Contactless power supply system and control method thereof

摘要

Power is contactlessly supplied from a power transmitting portion (12) to a power receiving portion (14). A transmitting efficiency detecting portion (18) detects the transmitting efficiency, and a determining portion (20) determines whether the transmitting efficiency is equal to or greater than a specified value. If the transmitted efficiency is less than the specified value, an obstruction may be present so power temporarily stops being transmitted. Power is then periodically transmitted with a minute power and the efficiency is detected. If the efficiency is equal to or greater than the specified value, power starts to be transmitted again with regular power.