| 摘要 |
PURPOSE:To make it possible to adjust power to a load without changing a frequency. CONSTITUTION:A set of serially connected switching elements S1 and S2 or S3 and S4 is connected to a DC power supply. An inductor L1, a capacitor C2, and a load (Z) are connected between each middle point of the switching elements S1 and S2 or S3 and S4. The switching elements S3 and S4 have an on-off timing range that is changed from the same phase to a 180-degree shifted phase with respect to a range of the switching elements S1 and S4. The switching elements S1 and S2 or S3 and S4 are turned on and off in each pair, but the switching frequency of the elements S1 and S2 is different from that of the elements S3 and S4. The on-state time of the switching elements S1 and S2 is made longer than at least two times that of the switching elements S3 and S4. Energy accumulated in an LC resonance circuit during the on-state of the switching elements S1 and S2 as a DC factor is supplied to a load (Z). |
