Wireless power transmission system

PURPOSE: A wireless power transmission system is provided to increase the efficiency of a wireless power transmission system by properly using a magnetic induction method and a magnetic resonance method according to the distance between coils for transmitting and receiving. CONSTITUTION: A transmission unit(120) generates power for charging a battery(180) before transmitting. The transmission unit includes a power generating device(122), and a power transmitting device(124). A receiving unit(140) receives the transmitted power and charges the battery. The receiving unit includes a power receiving device(142), and a driving device(144). A transmission controlling unit(160) controls to selectively use a magnetic induction method and a magnetic resonance method according to a distance between the transmission unit and a receiving unit. [Reference numerals] (122) Power generating device; (125) Variable capacitor; (144) Driving device; (162) Detecting device; (164) Transmission controlling device; (180) Battery;