Perpustakaan Digital ITB

Transmission systems using HVDC become an attractive option for power industry players due to their efficiency and reliability compared to HVAC, especially for bulk power, lengthy, and / or submarine electric power transmissions. In the HVDC system, space charge is an interesting phenomenon to be investigated related to the electric field distortion and to the degradation of insulation in the cable. Therefore, research on the charge space on the cable is essential to study. This study aims to observe the behavior of space charge on HVDC miniature cable considering the voltage level, polarity reversal, and electro-thermal stress. The tested miniature cable (mini-cable), model of HVDC cables, is copper core conductor cable with 3 mm-thick XLPE insulation with the semi conductive shield. The space charge measurements were achieved by the pulsed electro-acoustic (PEA) method. In order to contribute to the settlement of experimental means, we have investigated the effect of the experimental arrangement on the quality of the electro acoustic signal that can be obtained. Several voltages both in positive and negative polarity are applied to the cable with levels up to 35 kV. +35 kV and -35 kV are applied for observing space charges under-voltage polarity reversal. Some measurements were achieved under a thermal gradient of 7°C along the insulation of the cable. It was used to observe for the field redistribution and possible electro-thermal ageing effect on the cable. Space charge is measured using the pulse electric acoustic (PEA) method. Comparisons of the space charge patterns are performed. The effect of the electrical stress, polarity reversal, and electro-thermal stress on space charge behavior on XLPE insulation in HVDC miniature cables are obtained.