PEA Measurement on 525kV HVDC Cable Compliant with IEEE 1732 Recommendation

In 2017, IEEE proposed a procedure to evaluate the effect of space charge accumulation in extruded cables for HVDC applications with rated voltages up to 550kV. In this paper, the results of a measurement performed with the Pulsed Electro-Acoustic (PEA) method are reported, according to the guidelines of the IEEE recommendation. The measurement has been performed on a full-size cable with rated voltage of 525kV. The procedure involves a phase of positive volt-on (U0) and volt-off and another of negative volt-on (-U0) and volt-off. The results show that both in the positive volt-on phase (lasting 9 hours) and in the negative volt-on phase (lasting 6 hours), the electric field profile underwent an inversion process. Having performed a continuous acquisition of the charge profile, it was observed that the inversion occurs in both cases during the first hour. While the stabilization of the field profile occurred first in the negative volt-on phase.