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:
Jun. 14, 1994
Filed:
Sep. 18, 1992
Steven A Moran, Pittsburgh, PA (US);
Westinghouse Electric Corp., Pittsburgh, PA (US);
Abstract
A three-phase active filter for connection into a three-phase power distribution system to compensate undesirable harmonic deviations. A converter is electrically connected between the power distribution system and a DC energy storage element. The converter is selectively controlled by control means to effectuate a flow of energy between the system and the storage element to offset the harmonic deviations. To improve the dynamic response of the filter, the control means utilize vector control principles. Specifically, a synchronous fundamental vector of AC energy waveforms in the power distribution system is derived in a rotating reference frame. Fundamental reference signals are then produced in a stationary reference frame which are compared with corresponding actual condition signals. Error signals thus produced are then utilized to operate the converter. To compensate losses in the storage element and inverter, the control means preferably further comprise loss compensation means also utilizing vector control principles.