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:
Mar. 29, 2016
Filed:
Jul. 28, 2011
George W. Oughton, Jr., Raleigh, NC (US);
Yu Liu, Milwaukee, WI (US);
Debrup Das, Atlanta, GA (US);
Pasi S. Taimela, Wake Forest, NC (US);
Bobby L. Compton, Raleigh, NC (US);
George W. Oughton, Jr., Raleigh, NC (US);
Yu Liu, Milwaukee, WI (US);
Debrup Das, Atlanta, GA (US);
Pasi S. Taimela, Wake Forest, NC (US);
Bobby L. Compton, Raleigh, NC (US);
Eaton Corporation, Cleveland, OH (US);
Abstract
A fault in a DC power source, such as a battery string or a string of photovoltaic cells, is identified by detecting a change in an AC component of a residual current of the DC power source. In some embodiments, the DC power source is coupled to at least one DC bus and the methods further include generating an AC voltage on the at least one DC bus. For example, the DC power source may be coupled to a modulated DC bus of an uninterruptible power supply (UPS) system comprising an inverter having an input coupled to the DC bus. The inverter may be configured to generate an AC output voltage and the AC component has a frequency that is a harmonic of a fundamental frequency of the AC output voltage, such as a third harmonic of the fundamental frequency of the AC output voltage.