| 摘要 |
<p>An AC/AC converter includes first to sixth AC switches. A set of the first and second AC switch and a set of the third and fourth AC switch are connected in parallel with each other between both ends of an AC input. One end of the primary winding of a transformer is connected to the node of the first and second AC switches and the other end to the node of the fourth and third AC switches. One end of the secondary winding is connected to one end of the fifth AC switch and the other end to one end of the sixth AC switch. The other ends of the fifth and sixth AC switches are connected to one of the output terminals and the other output terminal is connected to the mid point of the secondary winding. The AC/AC converter further includes a control means which alternately operates a group of the first, third and fifth AC switches and a group of the second, fourth and sixth AC switches at a frequency higher than that of the input. The AC input repeatedly and alternately flows through the primary winding of the transformer in different directions at a frequency which is sufficiently higher than that of the AC input. Namely, the AC input is converted into AC of a higher frequency. An arbitrary voltage proportional to the turns ratio of the transformer appears on the secondary side of the transformer at the higher frequency. On the secondary side, the direction of the AC is again controlled by means of the secondary side AC switches which operate synchronously with the primary side AC switches, and the waveform of the AC closely resembles or is similar to the original waveform. Since a high frequency is applied to the transformer, the size of the transformer is reduced and the efficiency of the transformer is improved <IMAGE></p> |
