Patent · US Expired

Device and method for eliminating transformer excitation losses

US7646275B2 · kind B2 · utility

6Cited by
10References
12Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 6, 2003
Grant dateJan 12, 2010
Priority date
Expiry dateSep 26, 2024

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY04S20/20
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

The invention is a device and method for eliminating core excitation losses in a distribution transformer when the transformer is not supplying power to loads. The invention consists of sensors, a control circuit, a user interface and a power contactor. The power contactor is connected on the line side of a transformer and is opened or closed automatically based on preprogrammed time or load criteria determined by the control circuit. In one operational mode and when the transformer is disconnected from the line, the control board generates low power pulses at the transformer load connection points in order to “search” for loads. If a load is detected, the transformer is reconnected by way of contactor closure. If the transformer load drops to zero, for a predetermined amount of time, the transformer is again disconnected and the pulsed load search is reestablished.

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