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:
Apr. 12, 1994
Filed:
Dec. 11, 1991
Douglas C Folts, Mauston, WI (US);
Best Power Technology, Incorporated, Necedah, WI (US);
Abstract
A battery in a back-up power system is charged during the time that power is available from the main AC power system by utilizing the main power transformer and the main inverter. When power is available from the main AC power source, an AC voltage appears across the primary of the transformer, which is connected to the inverter. Switches in the bridge inverter are turned on for a relatively brief period of time to short the primary of the transformer causing current through the leakage inductances of the transformer to rapidly build up. When the switching devices are turned off, the inductances induce a current to continue to flow from the primary into the inverter through anti-parallel diodes, normally back biased by the voltage from the battery, into the battery thereby charging the battery with the energy stored in the transformer inductances. The inverter current reaches zero when the energy stored in the inductance is fully discharged. The cycle may be repeated by turning on the switching devices in the inverter bridge at periodic points in time, allowing the current in the inverter to dwell periodically at zero, or by immediately turning on the switching devices again when the current into the inverter reaches zero.