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:
Nov. 28, 2000
Filed:
Apr. 14, 1999
Walter Wissmach, Munich, DE;
Rudolf Bauer, Erpfting bei Landsberg am Lech, DE;
Hilti Aktiengesellschaft, Schaan, LI;
Abstract
A method of reducing feedback action on a timely flow of current, which is drawn by a load from a network via rectifier, by active filtering of upper harmonics, which are superimposed on a network first harmonic, with a power factor corrector circuit with a pulse-width modulation of a switch signal which influences the current drawn from the network and flowing through a boost-converter, with the method including dividing a current path between the rectifier (2) and the load (10) in a plurality of parallel channels (It, Jt), and providing in each channel (It, Jt) a similarly active filter, with switch signals of both active filters having a substantially same pulse-width modulation and being phase-sifted relative to each other so that a reduced ripple of the total current, which results form cumulative superimposition of currents in separate channels, is produced at a network input (9); and an active filter for effecting the method.