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. 02, 2014
Filed:
Jul. 14, 2011
Timothy N. Thacker, Christiansburg, VA (US);
Dushan Boroyevich, Blacksburg, VA (US);
Fred Wang, Knoxville, TN (US);
Rolando Burgos, Blacksburg, VA (US);
Timothy N. Thacker, Christiansburg, VA (US);
Dushan Boroyevich, Blacksburg, VA (US);
Fred Wang, Knoxville, TN (US);
Rolando Burgos, Blacksburg, VA (US);
Virginia Tech Intellectual Properties, Inc., Blacksburg, VA (US);
Abstract
A phase detector for a phase-locked loop includes a phase detector that is configured to become unstable, oscillate and drift rapidly in frequency in a predictable manner when a reference frequency signal is not available. When applied, for example, to a power converter connected to a power distribution grid, the predictable oscillatory and rapid frequency drift behavior when the phase detector is unstable allows very rapid and reliable detection of disconnection from the grid, referred to as islanding.