| 摘要 |
In an AC to DC power conversion circuit including a boost inductor (24) connected in series between a full-wave rectifier (18) and a DC load (12), a switch (38) is connected to selectively shunt boost inductor current from the load. Switch conduction is controlled by a pulse width modulator (62) generating switching pulses at a high fixed frequency. The pulse widths are automatically varied as a function of boost inductor current (44,42), load voltage (48,50), and an ideal sinusoidal waveform derived (54) from the AC input voltage to force the boost inductor current to closely conform to the ideal sinusoidal waveform and thus minimize harmonic distortion, while achieving load voltage regulation and near unity power factor. |
