| 摘要 |
PROBLEM TO BE SOLVED: To provide a power transmission device that can suppress occurrence of overvoltage or overcurrent.SOLUTION: A power transmission device has a power transmission antenna, an oscillation circuit, a control circuit and a communication circuit. The control circuit sets an initial value of a phase shift amount, outputs preliminary AC power of the voltage corresponding to the initial value to the oscillation circuit, stepwise reduces the phase shift amount from the initial value every predetermined time, and outputs, to the oscillation circuit, the preliminary AC power of each voltage corresponding to each phase shift amount which is stepwise reduced. When receiving a first response signal representing start-up of a control circuit of a power reception device from the power reception device through the communication circuit, the control circuit fixes the phase shift amount when the control circuit of the power reception device is started up, keeps the voltage corresponding to the fixed phase shift amount and transmits the AC power. |
