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. 04, 1998
Filed:
Nov. 29, 1996
Frederick A Stich, Wisconsin Rapids, WI (US);
Peter W Jungwirth, Wisconsin Rapids, WI (US);
Donald K Zahrte, Sr, Necedah, WI (US);
General Signal Corporation, Stamford, CT (US);
Abstract
A standby power system is provided having power conversion, output voltage control, and line-fault detection systems that make possible a significant reduction in the cost of the system. The standby power system provides backup power to a load, such as a computer system, when main AC line power fails. A system DC battery voltage is converted to an AC output voltage signal at line voltage levels by a power conversion system including a high frequency push-pull inverter, a light-weight low-cost high frequency transformer, a rectifier, and a line frequency inverter. The high frequency inverter is controlled to provide high frequency battery voltage pulse bursts separated by low frequency zero voltage dead times which are boosted by the transformer to line voltage levels and rectified by the rectifier. The line frequency inverter is controlled to provide the rectified line voltage level pulse bursts to the standby power system output in the form of a stepped square wave output signal at line frequencies. Rms and peak output voltage control is provided by a system controller based on a single digital output voltage control signal. The system controller detects the occurrence of AC line faults using a single digital line sense signal. Since analog-to-digital conversion of the power system input and output voltage waveforms is not required for line fault detection or output voltage control, the system controller may be implemented using a low-cost microprocessor.