| 摘要 |
PURPOSE:To enhance the efficiency of a rectifier by rectifying while pulse-width- modulating with high frequency, thereby responding at a high speed. CONSTITUTION:A rectifier is composed of a rectifying circuit 7 having a high frequency phase control function and a controller 8 for controlling it. The circuit 7 is composed of a transformer with an intermediate tap at the secondary side, a switching circuit of switch elements 11, 12, and a DC filter of a reactor 13 and a capacitor 14. This switching circuit generates a pulse of high frequency on the basis of an AC input, inverts the polarity of the pulse at every half cycle of the AC input to obtain a DC output of a pulse train aligned in the polarity. A DC output voltage Vc is controlled by altering the pulse width of the voltage Vb by varying the ratio of ON/OFF periods of the elements 11, 12. |
