Open AccessElectronic transformer performance evaluation and its impact on PMU
Author(s) -
Li Jue,
Liu Hao,
Martin Kenneth E.,
Li Jinsong,
Bi Tianshu,
Yang Qixun
Publication year - 2019
Publication title -
iet generation, transmission and distribution
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.92
H-Index - 110
eISSN - 1751-8695
pISSN - 1751-8687
DOI - 10.1049/iet-gtd.2019.0174
Subject(s) - phasor , harmonics , phasor measurement unit , transformer , rogowski coil , electronic engineering , engineering , voltage , electrical engineering , units of measurement , dc bias , control theory (sociology) , computer science , electric power system , electromagnetic coil , physics , power (physics) , control (management) , quantum mechanics , artificial intelligence
The electronic transformer of smart substations, which transfers primary signals, is important for measurements and controls. In this study, the transformation characteristics of a Rogowski electronic current transformer (ECT) are analysed theoretically. Then, experimental platforms are established to verify the analysis and study the impact of the transformation characteristics of the ECT and an electronic voltage transformer (EVT) on a phasor measurement unit (PMU) using standard test signals. The analysis and the testing results show that this ECT can transfer the phasor well under both steady and dynamic conditions. However, the harmonics introduced by the ECT may lead to the measurement errors of frequency and the rate of the change of the frequency (ROCOF) from the PMU. Therefore, a phasor algorithm with powerful DC offset and harmonics immunity is suggested for PMUs connected to the output of this type of ECT. For the EVT, the ROCOF measurements are easily affected as well. The EVT was also shown to be more sensitive to temperature than the potential transformer (PT).