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:
Feb. 05, 2008
Filed:
Aug. 11, 2006
Mukul Rastogi, Murrysville, PA (US);
Ronald Gaillot, Lower Burrell, PA (US);
Anthony C. Schneider, Monroeville, PA (US);
Ralph Flaugher, Jr., Allison Park, PA (US);
Yusuke Fukuta, Pittsburgh, PA (US);
Mukul Rastogi, Murrysville, PA (US);
Ronald Gaillot, Lower Burrell, PA (US);
Anthony C. Schneider, Monroeville, PA (US);
Ralph Flaugher, Jr., Allison Park, PA (US);
Yusuke Fukuta, Pittsburgh, PA (US);
Siemens Energy & Automation, Inc., Alpharetta, GA (US);
Abstract
A method for controlling at least two variable frequency drives connected in parallel. The method comprises, for each variable frequency drive, communicating a magnetizing current component value to a master controller, and receiving a speed demand, a flux demand, and an average magnetizing current component value from the master controller. The method also comprises determining a motor speed and a motor flux based on measurements of a stator voltage and current of a motor coupled to the variable frequency drive, determining a speed reference based on a torque current component value, and determining a flux reference based on the magnetizing current component value and the average magnetizing current component value. The method further comprises adjusting a torque current component based on the speed reference and/or adjusting a magnetizing current component based on the flux reference.