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. 22, 2011
Filed:
Jun. 02, 2008
Carlos Rodríguez Valdez, Glendale, WI (US);
Russel Kerkman, Milwaukee, WI (US);
David Dahl, Cedarburg, WI (US);
Jeffrey Mcguire, Franklin, WI (US);
Nickolay Guskov, Mequon, WI (US);
Carlos Rodríguez Valdez, Glendale, WI (US);
Russel Kerkman, Milwaukee, WI (US);
David Dahl, Cedarburg, WI (US);
Jeffrey McGuire, Franklin, WI (US);
Nickolay Guskov, Mequon, WI (US);
Rockwell Automation Technologies, Inc., Mayfield Heights, OH (US);
Abstract
A method and apparatus for identifying a ground fault in a motor drive system that includes at least one three phase power conditioner that is linked to three phase supply lines and to positive and negative DC buses, the method comprising the steps of controlling the power conditioner at an operating frequency to convert power, while controlling the power conditioner to convert power, controlling the power conditioner to apply a common mode signal on each of the three phase supply lines where the common mode signal has a frequency that is different than the operating frequency, sensing the common mode signal on at least one of the three phase supply lines and when the common mode signal on the at least one of the three phase supply lines is greater than a threshold level, indicating that a ground fault has occurred.