Power supply for lighting and luminaire

摘要

According to one embodiment, a power supply for lighting includes a rectifying circuit, a smoothing capacitor, and a current control circuit. The rectifying circuit rectifies a phase-controlled alternating-current voltage supplied to between a pair of input terminals. The smoothing capacitor is connected to a high-potential terminal and a low-potential terminal of the rectifying circuit. A first electric current flows to the current control circuit in a period when an absolute value of the alternating-current voltage is lower than a specified value. After a second electric current larger than the first electric current flows when the absolute value of the alternating-current voltage increases to be equal to or larger than the specified value, the current control circuit is shut off to reduce a current value to be smaller than the second electric current until the absolute value of the alternating-current voltage decreases to be lower than the specified value.

主权项

1. A power supply for lighting comprising:
a rectifying circuit configured to rectify a phase-controlled alternating-current voltage supplied between a pair of input terminals; a smoothing capacitor connected to high-potential and low-potential terminals of the rectifying circuit; and a current control circuit connected to the pair of input terminals, a first electric current flowing to the current control circuit in a period when an absolute value of the alternating-current voltage is lower than a specified value and, after a second electric current larger than the first electric current flows when the absolute value of the alternating-current voltage increases to be equal or larger than the specified value, the current control circuit being shut off to reduce a current value to be smaller than the second electric current until the absolute value of the alternating-current voltage decreases to be lower than the specified value.