Industrial installation for voltage-on space measurements in HVDC cables

This work is concerned with a facility for characterizing the insulation of power cables whilst submitted to high dc voltage. The presented tool allows to measure the real distribution of the electric field in the cable insulation, which can be significantly different from the capacitive (Laplace) field repartition, and is of interest in insulation design and survey. After reviewing the basics of the technique used (principle of the thermal step method), a detailed presentation of the device and of its validation is given. Results obtained with the installation in the frame of design of dc cables are then exposed.