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. 25, 2012
Filed:
Dec. 29, 2009
Mahesh M. Swamy, Gurnee, IL (US);
Tsuneo Joe Kume, Kitakyushu, JP;
Mahesh M. Swamy, Gurnee, IL (US);
Tsuneo Joe Kume, Kitakyushu, JP;
Yaskawa America, Inc., Waukegan, IL (US);
Abstract
A variable frequency drive comprises a diode rectifier receiving multiphase AC power from a source and converting the AC power to DC power. An inverter receives DC power and converts the DC power to AC power to drive a load. A link circuit is connected between the diode rectifier and the inverter and comprises a DC bus to provide a relatively fixed DC voltage for the inverter. A bus capacitor is across the bus. A soft charge circuit limits inrush current to the bus capacitor. The soft charge circuit comprises an inductor connected between the source and the link circuit and a switch circuit in the link circuit for selectively providing a semiconverter configuration or a full bridge converter configuration to provide two stage charging of the bus capacitor.