A preliminary investigation on the electrothermal aging effect on polymeric insulation for DC cables described in this paper shows that insulating material conductivity varies with aging and this can impact significantly on space charge accumulation and on partial discharge likelihood. Indeed, the DC partial discharge inception voltage, PDIVDC, can decrease with aging, thus favouring the inception of PD which were absent in an unaged insulation. On the contrary, permittivity is not affected by aging, thus partial discharge inception voltage in AC, PDIVAC, is not expected to vary during operation life of an electrical insulation system. Therefore, designing DC cables should take into account the variation with aging of quantities which are associated with partial discharge occurrence in steady state, that is, conductivity and its dependence on temperature and field, and space charge. This highlights the need to carry out adequate accelerated life tests preliminary to design and qualification of HV and MV DC cables.
Seri P., Montanari G.C., Albertini M., Franchi Bononi S. (2022). Electrothermal aging of DC cables and insulation electrical properties: conductivity, space charge and partial discharges. 345 E 47TH ST, NEW YORK, NY 10017 USA : Institute of Electrical and Electronics Engineers Inc. [10.1109/EIC51169.2022.9833209].
Electrothermal aging of DC cables and insulation electrical properties: conductivity, space charge and partial discharges
Seri P.;Montanari G. C.;
2022
Abstract
A preliminary investigation on the electrothermal aging effect on polymeric insulation for DC cables described in this paper shows that insulating material conductivity varies with aging and this can impact significantly on space charge accumulation and on partial discharge likelihood. Indeed, the DC partial discharge inception voltage, PDIVDC, can decrease with aging, thus favouring the inception of PD which were absent in an unaged insulation. On the contrary, permittivity is not affected by aging, thus partial discharge inception voltage in AC, PDIVAC, is not expected to vary during operation life of an electrical insulation system. Therefore, designing DC cables should take into account the variation with aging of quantities which are associated with partial discharge occurrence in steady state, that is, conductivity and its dependence on temperature and field, and space charge. This highlights the need to carry out adequate accelerated life tests preliminary to design and qualification of HV and MV DC cables.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
