Patent · US Active

Method and apparatus for testing the excitation characteristic of current transformer

US9400304B2 · kind B2 · utility

2Cited by
0References
15Claims
0Family size

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Key dates

Filing dateApr 24, 2013
Grant dateJul 26, 2016
Priority date
Expiry dateNov 21, 2034

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R31/62
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

This disclosure relates to the field of current transformers, for testing the excitation characteristic of a current transformer is disclosed. The method comprise applying alternately positive and negative DC voltages across terminals of secondary winding of a CT to be tested and acquiring a secondary current; constructing a mathematical model of the relationship between the secondary current and a root mean square (rms) equivalent voltage at rated frequency of the CT from the relationship between a magnetic flux of a secondary winding iron-core of the CT and the rms equivalent voltage; and generating an excitation characteristic curve according to the mathematical model. The method and apparatus of the embodiments may test CTs requiring lower testing voltage as well as CTs with knee-point up to tens of kV by supplying a relatively low voltage and power, which makes the embodiments widely applicable.

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