Despite the many submarine telecommunications and power cables laid world-wide there are fewer than ten published studies of their environmental effects in the refereed literature.This paper describes an investigation...Despite the many submarine telecommunications and power cables laid world-wide there are fewer than ten published studies of their environmental effects in the refereed literature.This paper describes an investigation into the effects of laying and operating the Basslink High Voltage Direct Current(HVDC)cable and its associated metallic return cable across Bass Strait in South East Australia.Over more than 95%of its length the cable was directly laid into a wet jetted trench given the predominantly soft sediments encountered.Underwater remote video investigations found that within two years all visible evidence of the cable and trench was gone at over a third of the transects at six deep water sites(32-72 m deep).At other deep water transects the residual trench trapped drift material providing habitat for the generally sparsely distributed benthic community.Diver surveys at both of the near shore sites(<15 m deep)on the northern side of the Strait also found the cable route was undetectable after a year.On the southern side,where the cable traversed hard basalt rock near shore,it was encased in a protective cast iron half shell.Ecological studies by divers over 3.5 years demonstrated the colonization of the hard shell by similar species occupying hard substrates elsewhere on the basalt reef.Magnetic field strengths associated with the operating cable were found to be within 0.8%of those predicted from theory with strength dropping rapidly with distance from the cable.Beyond 20 m the field was indistinguishable from background.展开更多
空间电荷积聚在电缆附件绝缘界面上会引起局部电场发生畸变,已成为直流电缆附件发展的主要制约因素。为此,提出了一种新的直流电缆附件设计理念,采用与电缆绝缘相似的交联聚乙烯材料模注在电缆绝缘层上制作成应力锥和附件的增强绝缘层,...空间电荷积聚在电缆附件绝缘界面上会引起局部电场发生畸变,已成为直流电缆附件发展的主要制约因素。为此,提出了一种新的直流电缆附件设计理念,采用与电缆绝缘相似的交联聚乙烯材料模注在电缆绝缘层上制作成应力锥和附件的增强绝缘层,使得直流电缆附件的增强绝缘层与电缆绝缘层在交界面处融成一体,一定程度上消除了界面,进而从根本上改善了原界面上空间电荷的积聚情况。依据该设计理念研发的±200 k V直流无界面电力电缆附件已经按照国际大电网会议CIGRE TB 496推荐的试验方法通过型式试验,验证了该设计理念的正确性。展开更多
文摘Despite the many submarine telecommunications and power cables laid world-wide there are fewer than ten published studies of their environmental effects in the refereed literature.This paper describes an investigation into the effects of laying and operating the Basslink High Voltage Direct Current(HVDC)cable and its associated metallic return cable across Bass Strait in South East Australia.Over more than 95%of its length the cable was directly laid into a wet jetted trench given the predominantly soft sediments encountered.Underwater remote video investigations found that within two years all visible evidence of the cable and trench was gone at over a third of the transects at six deep water sites(32-72 m deep).At other deep water transects the residual trench trapped drift material providing habitat for the generally sparsely distributed benthic community.Diver surveys at both of the near shore sites(<15 m deep)on the northern side of the Strait also found the cable route was undetectable after a year.On the southern side,where the cable traversed hard basalt rock near shore,it was encased in a protective cast iron half shell.Ecological studies by divers over 3.5 years demonstrated the colonization of the hard shell by similar species occupying hard substrates elsewhere on the basalt reef.Magnetic field strengths associated with the operating cable were found to be within 0.8%of those predicted from theory with strength dropping rapidly with distance from the cable.Beyond 20 m the field was indistinguishable from background.
文摘空间电荷积聚在电缆附件绝缘界面上会引起局部电场发生畸变,已成为直流电缆附件发展的主要制约因素。为此,提出了一种新的直流电缆附件设计理念,采用与电缆绝缘相似的交联聚乙烯材料模注在电缆绝缘层上制作成应力锥和附件的增强绝缘层,使得直流电缆附件的增强绝缘层与电缆绝缘层在交界面处融成一体,一定程度上消除了界面,进而从根本上改善了原界面上空间电荷的积聚情况。依据该设计理念研发的±200 k V直流无界面电力电缆附件已经按照国际大电网会议CIGRE TB 496推荐的试验方法通过型式试验,验证了该设计理念的正确性。
