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:
Sep. 06, 1994
Filed:
Dec. 16, 1991
Ned Mohan, St. Paul, MN (US);
Regents of the University of Minnesota, Minneapolis, MN (US);
Abstract
A circuit is provided for generating a current that is a harmonic of the frequency of the utility system and which is of a selected amplitude and phase to reduce the total harmonic distortion of a system that converts alternating current to direct current, or vice versa. The DC signal is sampled and by controlling switches, a sinusoidal current at the desired harmonic is generated, and is provided to impedance network that injects this current into the multiphase AC system used by the utility in a very low cost, easily controlled, and highly effective manner. The impedance network comprises a single inductor and capacitance connected in series through each of the phases of the utility, with the current signal having an amplitude that is selected to substantially eliminate harmonics which cause high distortion of the utility signal.