Figure 5.
The horizontal axis gives relative humidity R H from 0 to 35 per cent. The vertical axis gives current density J from 10 to the power of negative 11 to 10 to the power of negative 9 amperes per square metre on a logarithmic scale. Conditions are 20 degrees Celsius, 6 kilovolts per millimetre, and 0.6 megapascals. The sulfur hexafluoride electric conductivity model increases steadily from about 2 times 10 to the power of negative 11 amperes per square metre at 0 per cent relative humidity to about 5 times 10 to the power of negative 10 amperes per square metre at 35 per cent. Measurement values generally increase from approximately 3 to 4 times 10 to the power of negative 11 amperes per square metre below 6 per cent to values between about 1 and 5 times 10 to the power of negative 10 amperes per square metre above 20 per cent. Individual measurements vary around the model, with lower values near 12 and 27 per cent and higher values near 22, 26, and 31 per cent.Comparison of the measurement data of the current density in SF6 from Zavattoni, (2014) with the electrical conductivity model (12) multiplied with 6 kV/mm to obtain the resulting current density with respect to the gas humidity content RH3D Geometry Model of the HVDC GIL
Source: Authors’ own work