Bilateral Comparison of High-Voltage Capacitance and Dielectric Dissipation Factor at 50 Hz

National Institute of Metrology (NIM), China and National Measurement Institute, Australia (NMIA) carried out a comparison program, which included low-voltage (LV) capacitance, the voltage dependence of high-voltage (HV) capacitance, and the dielectric dissipation factor (DDF) at 50 Hz. The traveling standards included a LV standard capacitor, a dissipation factor standard, and a 100 kV compressed-gas capacitor. The capacitance and DDF of the standard capacitor, measured by the two institutes, agreed within 2 mu F/F and 2 x 10-6, respectively, at 50 Hz and 500 V. DDF measurements at nominal values of 0.00000, 0.0001, and 0.001 agreed within 6 x 10-6 at 50 Hz and 10 kV. The capacitance change of a 100 kV compressed-gas capacitor measured by the two institutes agreed within 2 mu F/F over the voltage range from 10 to 100 kV. The success of the program proved comparisons using a re-filled HV compressed gas capacitor and a LV standard capacitor can be conveniently used to validate the complete traceability chain of the measurement of HV capacitance at 50 Hz. The program also proved that DDF measurements with different implementations of traceability chain via capacitance and resistance would agree well within the uncertainties required by industrial measurements and a commercial DDF standard that has undergone international air travel would be sufficiently stable.