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:
Jan. 30, 2001
Filed:
Nov. 06, 1998
Neil C. Berglund, Kasson, MN (US);
Patrick K. Egan, Rochester, MN (US);
Steven W. Steele, Rochester, MN (US);
John V. Swenson, Oronoco, MN (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A power system includes a battery back-up unit (BBU) having back-up battery circuitry which provides battery back-up support for a plurality of power supplies each having a respective power factor correction circuit front-end with a boost stage. The voltages output from the boost stages of the power supplies are monitored and compared with respective reference threshold voltages to derive a signal which is used to bring battery back-up power on-line when a monitored voltage falls below a threshold voltage, which may be indicative of a loss of AC mains input voltage. AC mains input voltage is also monitored to detect a restoration and disconnect the battery back-up power. In the event that battery back-up is brought on-line due to a faulty power supply rather than a loss of AC mains input voltage, the faulty power supply can be masked and reported for repair.