Bootstrap Calibration of Inductive Voltage Dividers at Inmetro

TL;DR

This paper discusses the development of a bootstrap calibration system for inductive voltage dividers at Inmetro, aiming to significantly improve calibration uncertainty beyond current methods.

Contribution

It introduces a new bootstrap calibration transformer designed at Inmetro, inspired by PTB's system, to achieve lower uncertainty in inductive voltage divider calibrations.

Findings

Transformer built for bootstrap calibration at Inmetro.

Current calibration method uses standard capacitors with ~1E-6 uncertainty.

Goal to reduce uncertainty by at least a factor of 10.

Abstract

The Laboratory of Metrology in Electrical Standards of Inmetro (Lampe) has built, in 2010, a transformer which is able to perform inductive voltage divider ratio calibrations using the bootstrap method. This transformer was idealized according to the design adopted at Physikalisch-Technische Bundesanstalt (PTB), and has very similiar characteristics to that system. Lampe's bootstrap system is not yet in operation, and DIT calibrations are presently being carried according to a triangular set of measurements involving standard capacitors. This method, though, has uncertanties limited to a few parts in 1E6; the primary objective of Lampe's bootstrap system project is to achieve uncertanties at least 10 times smaller than this.