Patent · US Expired

Emergency standby system for automatic transfer from utility power to a battery powered system

US4167680A · kind A · utility

15Cited by
2References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 13, 1977
Grant dateSep 11, 1979
Priority date
Expiry dateMay 13, 1997

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02B70/30
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An emergency standby power system for automatic transfer from utility power to a battery powered inverter when a normal source of utility power is interrupted to a given load, and for automatic re-transfer to utility power when it is restored. The inverter includes SCR circuitry whereby commutation failure during start-up and shut-down is prevented by applying power to the inverter prior to the application of the gate drive during start-up, and removing power from the inverter prior to the removal of the gate drive during shut-down. Further, the control circuitry ensures that the first SCR gated on will operate for a complete one-half cycle, thereby fully charging the commutating capacitor for reliable commutation off of the first SCR before turning on the second SCR. The control circuitry also permits the inverter to start up even if it is presented with a short circuit and operate without damage.

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