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:
May. 17, 2011
Filed:
Aug. 18, 2008
Applicant:
Markku Talja, Järvenpää, FI;
Inventor:
Markku Talja, Järvenpää, FI;
Assignee:
ABB OY, Helsinki, FI;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02J 5/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
A method and an apparatus for damping voltage oscillation of a voltage intermediate circuit of a frequency converter, the frequency converter comprising a half controlled rectifier bridge coupled to a supply network. The method comprises determining magnitude (U) of voltage of the voltage intermediate circuit, determining magnitude (U) of rectified voltage of the supply network, forming a derivative of a difference (U−U) between the rectified voltage of the supply network and the voltage of the voltage intermediate circuit, delaying firing of controllable components of the rectifier bridge on the basis of the formed derivative.