Power supply apparatus and image forming apparatus
US8554101B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 18, 2011 |
| Grant date | Oct 8, 2013 |
| Priority date | — |
| Expiry date | Dec 17, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M3/33507
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A power supply apparatus needs to control an output voltage to a target voltage for a short time. A power supply apparatus of the present invention detects voltages output from a piezoelectric transformer. The power supply apparatus also detects peak values in a plurality of detected voltages according to a plurality of frequencies of pulse signals for the piezoelectric transformer, and identifies a frequency corresponding to the highest peak value, and a frequency corresponding to a next peak value next to and on a higher- or lower-frequency side of the frequency corresponding to the highest peak value. Moreover, the power supply apparatus sets an initial frequency used when starting to control the output voltage of the piezoelectric transformer to the target voltage, within a frequency range between the two identified frequencies.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.