Bilateral comparison of current transformer measuring systems of NCHVM and PTB

摘要

An intercomparison of current transformer calibration systems was performed between National Center For High Voltage Measurement (NCHVM) and Physikalisch-Technische Bundesanstalt (PTB) in order to confirm their measurement capabilities. A current transformer was used as travelling standard with transformer ratios of 5A/5A, 10A/5A and 100A/5A at a frequency of 50 Hz and at ambient temperatures of $23^{circ}mathrm{C}pm 3^{circ}mathrm{C}$. The measurements has been performed at test points varying from 5% to 120% of the rated current. For these three ratios, the test results differ by no more than 1.3 parts in 10⁶ for the ratio error and $2.0 mu mathrm{rad}$ for the phase displacement.