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. 15, 2009
Filed:
Jan. 23, 2007
Applicant:
Janne Salomäki, Hyvinkää, FI;
Inventor:
Janne Salomäki, Hyvinkää, FI;
Assignee:
ABB OY, Helsinki, FI;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H02M 1/36 (2007.01);
U.S. Cl.
CPC ...
Abstract
A method for starting the modulation of a frequency converter, which method comprises the steps of receiving reference voltages (s, s, s; U), generating output switch commands from the reference voltages. The generation of output switch commands comprises further a step, in which the ratio (d) of active time (T) in a modulation period (T) of selected zero vector and the total active time (T+T) of zero vectors in a modulation period is changed from a first predetermined ratio, which is substantially 0 or 1, to a second predetermined ratio, which is substantially 0.5.