The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 08, 2014
Filed:
Dec. 21, 2010
Yukihiro Nishikawa, Hino, JP;
Yukihiro Nishikawa, Hino, JP;
Fuji Electric Co., Ltd., Kawasaki-Shi, JP;
Abstract
A current flowing through a switching element () of a power supply is detected by an AC current transformer (), and a capacitor () is charged by a voltage corresponding to the current. A reduction factor of the terminal voltage of the capacitor in an off period of the switching element () is calculated based on an amplification factor of the terminal voltage of the capacitor, an absolute value of an instantaneous value of an input power supply voltage, and an instantaneous value of a direct current output voltage, and the capacitor is discharged so that the terminal voltage of the capacitor decreases by the reduction factor in an off period of the switching element (). A current flowing through an inductor () is estimated from the terminal voltage of the capacitor.