Patent ID: 9270138
Filing Date: 2016-02-23
CPC Classification: B60L,B60M,H01M,H02J,Y02E,Y02T

Claim Text:
1. An electric power transmission system that transmits electric energy via an electromagnetic field from a power transmission antenna to a power receiving antenna, comprising: an inverter unit that converts DC voltage to AC voltage of a predetermined frequency to output; a power transmission-side control unit that controls a drive frequency of the inverter unit and a voltage value of DC voltage input to the inverter unit, and controls power output from the inverter unit; the power transmission antenna to which AC voltage is input from the inverter unit; a rectifying unit that rectifies an output of the power receiving antenna to obtain DC voltage, and outputs the DC voltage; a step-up and step-down unit that steps up or down DC voltage output from the rectifying unit to output; a battery that is charged with an output of the step-up and step-down unit; and a power receiving-side control unit that controls the step-up and step-down unit in such a way as to charge the battery with maximum efficiency, and thereby controls in such a way that the drive frequency of the inverter unit remains unchanged regardless of a coupling coefficient between the power transmission antenna and the power receiving antenna.