To make a transition into a matching state in a short time while avoiding an increase in size.
A power transmission device includes: a signal generation part which generates an AC signal S1; a transmission antenna 12 which is supplied with the AC signal S1, and generates an electromagnetic field; and a first matching part 13 which has variable capacitor circuits 13a, 13b, and matches the signal generation part and the transmission antenna 12 with each other. The variable capacitor circuit 13a includes: a plurality of capacitor groups (capacitors 32a, 33a, etc.) which can be connected in parallel; a plurality of diodes 34a, 35a, etc. which are arranged corresponding to the respective capacitor groups, and switch a parallel connection state of the plurality of capacitor groups. The variable capacitor circuit 13b includes: a plurality of capacitor groups (capacitors 32b, 33ba, etc.); and a plurality of diodes 34b, 35b, etc. which switch a parallel connection state of the plurality of capacitor groups.
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