Patent · US Expired

Method and apparatus for providing battery charging in a backup power system

US5302858A · kind A · utility

78Cited by
13References
22Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 11, 1991
Grant dateApr 12, 1994
Priority date
Expiry dateDec 11, 2011

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02J2207/20
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

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 t…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.