| 摘要 |
PROBLEM TO BE SOLVED: To sharply reduce the noise of a power unit which has the power factor improving function. SOLUTION: A power factor improving converter PFC 5 modulates the ripple voltage appearing in the output voltage to a DC-DC converter 6 to 10 Vp-p or higher, whereby the DC-DC converter 6 changes its oscillation frequency, according to the ripple voltage contained in the DC voltage from the power factor improving converter PFC 5. |
