| 摘要 |
PURPOSE:To control a source current so as to be a sine wave shape, and to suppress the ripple of a DC output voltage by controlling a conduction ratio. CONSTITUTION:A difference between a DC voltage detection signal 14 and a DC voltage instruction 15 is calculated, and if the DC voltage detection signal 14 is larger, a proportion gain K is increased, and if the DC voltage instruction 15 is larger, the proportion gain K is decreased. Namely, for instance, in a case that the DC voltage detection signal 14 is larger, the proportion gain K is increased, and a conduction ratio instruction value 9 is decreased, and therefore, an input current decreases, and an input power decreases. Accordingly, a power to be transmitted to a DC power side decreases as well, and the DC output voltage Ed decreases. Then, an above-mentioned operation is repeated until the deviation of the DC voltage detection signal 14 and the DC voltage instruction 15 comes to be zero, and the DC voltage Ed can be controlled. Thus, reliability against a voltage variation or a noise can be improved, and the ripple of the DC output voltage can be suppressed, and at the same time, a power factor is improved. |
