| 摘要 |
PROBLEM TO BE SOLVED: To perform constant current control or constant voltage control in power supply to a load (secondary battery) without using a DC-DC converter.SOLUTION: High frequency AC power outputted from a high frequency power source 21 of a power transmission device 2 is wirelessly transmitted to a power reception device 3 by a power transmission part 23 and a power reception part 31 which are coupled in a magnetic field manner, and converted into DC power by a rectifying and smoothing circuit 32 and a battery 34 is charged therewith. A battery voltage Vand a charging current Iof the battery 34 are detected by a voltage/current detector 33 and fed back to a control part 24 by communication units 25 and 35. On the basis of the detected battery voltage Vand charging current I, the control part 24 calculates a control target value of output power in the constant current control and the constant voltage control and controls the output power of the high frequency power source 21 in such a manner that power to be supplied to a load becomes the control target value. At such a time, the high frequency power source 21 outputs the pulse-like high frequency AC power having a high level term and a low level term by the control part 24.SELECTED DRAWING: Figure 1 |
