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:
Aug. 12, 2014
Filed:
Jul. 18, 2011
Qian LI, Blacksburg, VA (US);
Fred C. Lee, Blacksburg, VA (US);
Ming Xu, Blacksburg, VA (US);
Chuanyun Wang, Jiangsu, CN;
Qian Li, Blacksburg, VA (US);
Fred C. Lee, Blacksburg, VA (US);
Ming Xu, Blacksburg, VA (US);
Chuanyun Wang, Jiangsu, CN;
Virginia Tech Intellectual Properties, Inc., Blacksburg, VA (US);
Abstract
Light load efficiency of a power factor correction circuit is improved by adaptive on-time control and providing for selection between a continuous conduction mode and a discontinuous conduction mode wherein the discontinuous conduction mode increases time between switching pulses controlling connection of a cyclically varying voltage to a filter/inductor that delivers a desired DC voltage and thus can greatly reduce the switching frequency at light loads where switching frequency related losses dominate efficiency. The mode for controlling switching is preferably selected for each switching pulse within a half cycle of the cyclically varying input voltage. A multi-phase embodiment allows cancellation of EMI noise at harmonics of the switching frequency and adaptive change of phase angle allows for cancellation of dominant higher order harmonics as switching frequency is reduced.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile