High-voltage DC (HVDC) cables show more efficiency than high-voltage AC cables over the long distance power transmission and have attracted significant attention recently due to rapid developments in off-shore wind farm. Polypropylene laminated paper (PPLP) insulation based HVDC cables have provided a reliable operation for many years and are the highest voltage level in operation at the moment. In this study, the authors intend to understand the electrical performance of PPLP insulation system by examining space charge in detail, especially at the interfaces. It has been found that the interface between polypropylene and Kraft paper acts as trap for charge carriers, resulting in an optimal electric field distribution in PPLP insulation system. The optimal electric field distribution enhances overall electrical performance of PPLP insulation, including higher dc breakdown strength and lower electrical conductivity.

在远距离输电中，高压DC（HVDC）电缆比高压AC电缆具有更高的效率，并且由于近海风电场的迅猛发展，最近引起了广泛的关注。聚丙烯层压纸（PPLP）绝缘HVDC电缆已经提供了可靠的运行多年，并且是目前运行中的最高电压水平。在这项研究中，作者打算通过详细检查空间电荷（尤其是在接口处）来了解PPLP绝缘系统的电气性能。已经发现，聚丙烯和牛皮纸之间的界面充当电荷载体的陷阱，从而在PPLP绝缘系统中产生最佳的电场分布。最佳的电场分布可增强PPLP绝缘的整体电气性能，