Recent developments on high current measurement using current shunt

Abstract

The Short‐circuit Testing Liaison (STL) is the organization that consists of high power testing laboratories of the world. Member laboratories perform short‐circuit tests under uniform interpretations of the IEC standards agreed through technical discussions and information exchanges among them. One of the recent projects that the STL has been working on is to establish uncertainty and traceability of high current measurement by international comparison tests with reference shunts. In concert with this project, the IEC Working Group is preparing the new standard for high current measurements. Copyright © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

Development of Reference Shunt for Short‐Time Alternating High Current Tests and Study of Measuring System

“…The considered uncertainty factors are explained below. (4) Interference test: In the interference test at commercial frequency, the shunt was placed at 0.5 m apart from a conductor energized by asymmetrical current of 290 kA peak (80% of the available limit), and the current induced by the conductor was measured. (2) Scale factor test: The three shunts were connected in series, the symmetrical and the asymmetrical ac current of 10 kA was conducted for 0.1 s, and the deviation of measured peak current with respect to average value for the three shunts was obtained at every half-wave of the current.…”

“…The developed shunt has been used as a standard in round-robin comparative tests conducted by STL since 2005 in high power laboratories in Europe, North America, Asia, and Oceania [4][5][6][7]. Domestic laboratories affiliated with JSTC also participate in these tests.…”

“…This value was adopted as the most severe case, and the probability distribution of uncertainty was considered to be uniform. (4) Interference test: In the interference test at commercial frequency, the shunt was placed at 0.5 m apart from a conductor energized by asymmetrical current of 290 kA peak (80% of the available limit), and the current induced by the conductor was measured. In this case, the shunt was not connected to the inducing conductor.…”

Calculation of resistive current transducer parameters

“…To choose the overall dimensions it is necessary to take into account resistive element superheat temperature, representing the difference between surface temperature of resistive element and ambient temperature [3].…”

Multiplicative Method for Reduction of Bias in Indirect Digital Measurement Result

“…Shunt resistors have been extensively used in power electronics, see for instance [7,8], due to their low cost and relative simplicity, while providing reasonable accuracy. Current-technology precise AC shunts are implemented with rated resistance from 0.00001 to 100 Ohm at currents of 0.005 A through 500 kA to be applied in the 50 Hz to 1 MHz frequency range [9].…”