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:
Dec. 24, 1991
Filed:
Mar. 15, 1991
Applicant:
Inventors:
Alex J Severinsky, Silver Spring, MD (US);
Sundar Rajagopalan, Lanham, MD (US);
Assignee:
Viteq Corporation, Lanham, MD (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02J / ;
U.S. Cl.
CPC ...
307 66 ; 363 72 ;
Abstract
Two single phase uninterruptible power supplies are coupled together and controlled such that the two-phase output voltage is matched in frequency and phase with the electrical power provided by the electric utility. The phase difference between the electric utility power lines is measured and stored as a reference signal. When electrical power from the electric utility is lost, the stored reference signal is used to control a master and slave UPS to deliver two-phase power having the same frequency and phase.