Transient Oil Pressure Rise at EHV Pipe-Type Cable Faults

Since various phenomena resulting from earth faults in pipe-type cables have not yet been sufficiently clarified, the authors made fault tests on pipes of 105 and 254 mm in diameter and 20 to 60 m in length. As a result, arc voltages were found to be nearly constant, independent of the magnitude of fault current. Moreover, the mechanism of transient pressure rise and the relation between arc energy and oil pressure rise were elucidated. Calculated results agreed fairly well with experimental data.