Digital Measurement of Line Current with the Use of Virtual Short Circuit Method

Vladimir Vujicic, Aleksandar Radonjic, Dragana Naumovic-Vukovic, Nemanja Gazivoda, Platon Sovilj
Abstract:
The paper describes a method of very accurate measurement of line current using a current transformer (CT) in a virtual short circuit. The key systematic error, amplified error due to offset of operational amplifier that leads CT in a virtual short circuit, is easily calculated using a stochastic digital measurement method and eliminated from measured RMS value of line current. Since the 2-bit stochastic digital measurement method is defined using a very simple hardware which has a small number of sources of systematic error, sources are easily identified and it is described how to eliminate these errors. A complete measurement scheme of line current is presented and applied in quadruple three-phase power analyser with MM4 type designation. MM4 is a key component of the redundant measuring system in the Electric Power Grid of Serbia.
Keywords:
digital stochastic measurement, line current, current transformer
Download:
IMEKO-TC4-2017-051.pdf
DOI:
-
Event details
IMEKO TC:
TC4
Event name:
TC4 Symposium 2017
Title:

22nd IMEKO TC4 Symposium and 20th International Workshop on ADC Modelling and Testing
"Supporting world development through electric&electronic measurements"

Place:
Iasi, ROMANIA
Time:
14 September 2017 - 15 September 2017