The development of a computer-controlled current-comparator-based calibration system to determine the current ratio errors of high-voltage conventional and nonconventional current transformers (CTs) under actual operating conditions of high-voltage and distorted current waveforms up to 100 kV and 2000 A is described. The ratio errors of a CT are affected by the applied high voltage due to capacitive currents flowing in its winding. The errors are also affected by the phase angle of the primary currents with respect to the operating high voltage. Therefore, the new calibration system allows the phase angle of the test primary currents to be adjusted at power factors of zero lag through unity to zero lead. The uncertainty k = 2 of the new calibration system is estimated to be not more than 20 × 10-6 for both the in-phase and quadrature components of the measured ratio errors.

The development of a computer-controlled current-comparator-based test system for calibrating high-voltage revenue metering equipment under actual operating conditions of high voltage/high current with sinusoidal or nonsinusoidal voltage and current waveforms is described. Measurements can be made at any power factor from zero lead or lag through unity, at line-to-ground voltages up to 100 kV and currents up to 2000 A. The magnitude and phase uncertainties ( k = 2) of the new calibration system are estimated to be not more than 100 μW/VA and 100 μrad, and 200 μW/VA and 200 μrad for sinusoidal and nonsinusoidal conditions, respectively. The calibration system can be used in the laboratory or on-site in high-voltage substations.

The development of a computer-controlled system for the calibration of high voltage revenue metering systems under actual operating conditions of high voltage and sinusoidal/non-sinusoidal voltage and current waveforms will be described. Measurements can be made at any power factor from zero lag through unity, at voltages up to 100 kV line-to-ground voltage and currents up to 2000 A. The magnitude and phase uncertainties (k=2) are estimated to be not more than 50 μW/VA and 50 μrad, and 100 μW/VA and 100 μrad for sinusoidal and non-sinusoidal conditions, respectively.

The development of a current-comparator-based calibration system to evaluate the current ratio errors of high voltage conventional/non-conventional current transformers, under actual operating conditions of high voltage and distorted current waveforms, up to 100 kV and 2000 A will be presented. The importance and critical need of such calibration system will be described.

The paper describes a test procedure, the test waveforms, and the reference equipment used to calibrate the voltage and current total harmonic distortion (THD) measuring functions of multi-function electrical standards. It also shows that it is possible to establish traceability to the SI units for the THD measurements by measuring the voltage and power of the test waveforms with voltmeters and wattmeters that are traceable to SI. Results of recent calibrations are discussed.

This paper describes some improvements to the accuracy of the on-site measuring system of the National Research Council of Canada (NRC) Travelling Standard Program. This NRC service provides traceable calibrations of the multifunction electrical standards that electrical utilities and other organizations use to test and verify electricity revenue meters. The calibration program can be used to show that the measurements of the electricity revenue meters are traceable to the national standard, a requirement of the trade metrology legislation in Canada.

This paper describes an on-site measurement program of the National Research Council of Canada (NRC). The NRC service provides calibrations of the multifunction electrical standards that electrical utilities and other organizations use to test and verify electricity revenue meters. The calibration program can be used to show that the measurements of the electricity revenue meters are traceable to the national' standard, a requirement of the trade metrology legislation in Canada. Some calibration results of two types of commonly used electrical standards are also discussed.