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:
Apr. 20, 2010
Filed:
Jun. 28, 2007
Kempei Seki, Tokyo, JP;
Kempei Seki, Tokyo, JP;
Mitsubishi Electric Corporation, Chiyoda-Ku, Tokyo, JP;
Abstract
An active filter that can remove harmonic noises other than the fundamental wave in a system having many unspecified harmonics and can contribute to the stable operation of the system, and improvement in the quality of power is provided. Using the following power equation (1) for a single-phase circuit as a basic expression, an active power effective value P and a reactive power effective value Q are obtained by integration operation with an active power instantaneous value and a reactive power instantaneous value, an instantaneous voltage estimation value is calculated, the system side fundamental wave current is obtained based on these values, and then the system side fundamental wave current is subtracted from the load current to obtain compensation current as the output of the active filter.