| 摘要 |
PURPOSE:To stabilize an operating state or a load on starting and reduce a stress applied to a circuit element. CONSTITUTION:In a first switching circuit A, an AC power source is transformed into a DC power source. A second switching circuit B is operated by utilizing a power source of a direct current supplied from the first switching circuit A. The second switching circuit B supplies electric power to a load 5. The first and second switching circuits A, B are provided with control circuits 3, 4 for controlling the drive of a switching element, respectively. The first switching circuit 13 is operated in such a state that an output is limited to a low value. After an elapse of a predetermined period, the second switching circuit B comes into an operating state where a desired output can be obtained. Furthermore, after the operating state of the second switching circuit B is stabilized, the first switching circuit A is operated. |
