Patent · US Expired

Load voltage based tap changer monitoring system

US5619121A · kind A · utility

22Cited by
5References
18Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 29, 1995
Grant dateApr 8, 1997
Priority date
Expiry dateJun 29, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG05F1/147
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A tap changer including a tap positionable to vary the winding ratio of the transformer in response to changes in an electric load on the transformer is disclosed herein. The transformer includes an electric drive which is electrically powered to selectively position the tap to effect incremental changes of the winding ratio. The transformer includes a monitoring system which monitors the load voltage of the transformer with at least one potential transformer which produces signals which are converted to digital data values stored in a circular data buffer. Each time control signals are applied to the electric drive and a subsequent tap change indication is detected, the first and last data values in the circular buffer are compared, and when the difference between the values exceeds a predetermine limit, the system updates a tap position value which represents the position of the tap.

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