| 摘要 |
In a DC power supply circuit (1), when an instantaneous value (Vin) of a voltage from a rectifier circuit (2) is higher than or equal to a voltage (VC2) across terminals of a capacitor (C2), in an ON period of a switching element (Q1), current flows along a first current path, from a high-potential output terminal of the rectifier, through a load (11), an inductor (L2), and the switching element in the stated order, and into a low-potential output terminal of the rectifier, and in an OFF period of the switching element, current flows along a second current path, from the high-potential output terminal of the rectifier, through the load, the inductor, a diode (D1), and the capacitor in the stated order, and into the low-potential output terminal of the rectifier. |
| 主权项 |
1. A direct current (DC) power supply circuit comprising;
a rectifier circuit rectifying alternating current (AC) supplied thereto from an AC power supply; and a voltage conversion circuit connected across output terminals of the rectifier circuit, converting a voltage from the rectifier circuit, and outputting a converted voltage to a load, the voltage conversion circuit comprising:
an inductor having terminals, a first one of which is connected, via the load, to a high-potential one of the output terminals of the rectifier circuit;a switching element connected between a second one of the terminals of the inductor and a low-potential one of the output terminals of the rectifier circuit;a capacitor having terminals, a first one of which is connected to the low-potential one of the output terminals of the rectifier circuit; anda first unidirectional element connected between a second one of the terminals of the capacitor and the second one of the terminals of the inductor, wherein when an instantaneous value of the voltage from the rectifier circuit is higher than or equal to a voltage across the terminals of the capacitor,
in an ON period of the switching element, current flows along a first current path from the high-potential one of the output terminals of the rectifier circuit, through the load, the inductor, and the switching element in the stated order, and into the low-potential one of the output terminals of the rectifier circuit, andin an OFF period of the switching element, current flows along a second current path from the high-potential one of the output terminals of the rectifier circuit, through the load, the inductor, the first unidirectional element, and the capacitor in the stated order, and into the low-potential one of the output terminals of the rectifier circuit. |
