Traceability of Low-Power Voltage Transformer for Medium Voltage Application

Abstract

In this paper, the measuring and calibration techniques useful for ensuring the traceability of nonconventional voltage transformer (VT), used in ac power plant up to 52 kV, are described and discussed. In particular, a setup made by commercially available devices is presented and an in-depth accuracy analysis is performed by considering all the uncertainty sources located in the measurement chain. The obtained results prove that it can be used for the calibration of 0.5 accuracy class low-power VTs. In addition, the sources that contribute more to the uncertainties on the ratio and phase errors are highlighted and suggestions on where to act to further improve the accuracy of the presented setup are given

Error reduction of phasor measurement unit data considering practical constraints

“…Unfortunately, that method could not be applied for AC‐CT calibration. Pasini et al [18] describe calibration techniques that ensured traceability of non‐conventional VTs. However, that methodology is designed to work only up to 52 kV.…”

Calibration Procedure to Test the Effects of Multiple Influence Quantities on Low-Power Voltage Transformers

“…Instead, the LPITs' calibration scenario is quite limited, but increasing day-by-day. For example, calibration techniques for electronic transformers are presented in studies by Tong et al [14] and Cayci and Kefeli [15], while in some studies [16][17][18][19][20] both current and voltage LPITs are tested at rated and off-nominal conditions. Finally, particular attention is given to the calibration of Rogowski coils and low-power current transformers (LPCTs) in other studies [21][22][23][24].…”

Electronic transformer performance evaluation and its impact on PMU

“…A number of studies have been published on the performance of instrument transformers. A low-power voltage transformer for medium voltage application was tested in [14], specifically for the application of international standards about instrument transformers for power quality measurements. Skubis and Piaskowy [15] proposed a method and circuit for determination of the ratio error of an inductive autotransformer voltage divider.…”