Patent ID: 9728979
Date: 2017-08-08
CPC Classifications: H01F,H02J

Claim:
1. A contactless power transmission circuit for transmitting a power via a magnetic field from a power transmitting coil to a power receiving coil, comprising: a driving circuit for supplying an alternating voltage to the power transmitting coil, a rectifier circuit for rectifying a voltage generated in the power receiving coil with a magnetic field generated by the power transmitting coil, a transmission current detecting circuit for detecting a transmission current flowing through the power transmitting coil, an output voltage detecting circuit for detecting an output voltage of the rectifier circuit, and a control circuit for controlling a period of the alternating voltage output from the driving circuit, wherein the control circuit is set to calculate a first command value and a second command value which are command values for the period of the alternating voltage, and use a smaller one of either of the first command value and the second command value as a command value for the period of the alternating voltage, the first command value is a command value based on a difference between a detected value of the output voltage detected by the output voltage detecting circuit and a target value of the output voltage, and the second command value is a command value calculated based on a difference between a detected value of the transmission current detected by the transmission current detecting circuit and a target value of the transmission current.