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:
Aug. 27, 2002
Filed:
Jan. 31, 2002
Tadamitsu Yoshikawa, Tokyo, JP;
Hiroaki Matsumoto, Saitama-ken, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
In a power conversion device according to the present invention, an AC power source voltage signal Vac which is the instantaneous value of AC power source detected by a power source voltage detection circuit comprising a transformer , rectifier and A/D converter is averaged by an averaging circuit and an average AC power source voltage signal Vave is output. This average AC power source voltage signal Vave and AC power source voltage signal Vac are compared in comparator and, if their deviation is more than a prescribed value, a power source voltage drop detection signal PSF_S is output. Spurious detection of power source voltage drop resulting from the effect of power source fluctuations can thereby be prevented.