Cable Test and Breakdown Voltage Determination of Joysense Cable Insulation

Lightning Impulse Ageing of Hv Cable Insulation

Lightning impulses can lead to accelerated ageing of extruded cables. Electrical behaviour of a dielectric material when experiencing a lightning impulse is different to that for DC or power frequency applied voltages. Pre-designed shaped HDPE material samples have been manufactured using a mould tool. The samples then have been electrically aged using an impulse generator. A real-time software...

Improved Lead-Free Wire and Cable Insulation Performance Using Nanocomposites

The Conduction Characteristics of Electrical Trees in XLPE Cable Insulation

Depending on the morphology of the material and applied voltage frequency, three kinds of electrical trees can exist in cross-linked polyethylene (XLPE) cable insulation, which are conducting, non-conducting, and mixed trees with different growth mechanisms. It is suggested that when the needle is inserted into large spherulites, conducting trees will form in those spherulites; when it is inser...

Determination of Moisture Content in Mass Impregnated Cable Insulation Using Low Frequency Dielectric Spectroscopy

The variations in the low frequency dielectric spectra of mass impregnated insulation depending on its moisture content have been investigated. For the calibration purposes a number of the impregnated paper samples was kept in the desiccators where different relative humidities were maintained. Thus obtained moisture content in the samples ranged from 1 % up to 6 %. The variations of the comple...

A Methodology for the Assessment of Hvdc-xlpe Cable Insulation

The purpose of this work is to present and to discuss a methodology for the assessment of materials intended to HVDC-XLPE cables, particularly as regards the evaluation of the effects of material formulation on space charge accumulation within the insulation. Sample design, testing method and protocol and criteria used for the material evaluation are specifically considered. It will be shown th...