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:
Dec. 17, 2002
Filed:
Mar. 03, 2000
Applicant:
Inventor:
Ryoji Maruyama, Kawasaki, JP;
Assignee:
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01R 1/124 ;
U.S. Cl.
CPC ...
G01R 1/124 ;
Abstract
A voltage (V ) and a current (A ), input from input terminals (T ) and (T ), are A/D converted to 1-bit output data by delta modulators and 1-bit output data of the delta modulator is delayed, using a phase-shifting circuit implemented by either a RAM (semiconductor memory) or shift registers, by an amount equivalent to 90° of the input voltage (V ), before a subsequent circuit performs a calculation of a reactive power. This circuit configuration reduces analog circuitry and enables a compact, low-cost implementation, even for use in an LSI.