挤包绝缘高压直流电缆的发展

Development of High Voltage Direct Current Extruded Cables

挤包绝缘高压直流电缆是实现大电网柔性互联、远距离大容量输电和新能源电力规模化利用的关键电力设备之一。按照挤包绝缘高压直流电缆系统的开发脉络,从挤包绝缘高压直流电缆绝缘材料的开发、电缆附件相关技术、电缆系统的试验方法与检测技术、国内外工程应用等方面,全面综述了挤包绝缘高压直流电缆的技术发展现状。特别针对高压直流电缆用绝缘材料的直流电导和空间电荷特性研究、直流电缆系统的型式试验和预鉴定试验方法、全尺寸电缆空间电荷测量和直流局部放电检测技术等热点问题进行了分析,提出了目前挤包绝缘高压直流电缆技术中亟待解决的问题,包括研究现有电缆绝缘的电导和空间电荷特性与长期老化行为及其机理,开发更高电压等级直流电缆用绝缘材料,研发附件材料并优化附件结构设计,提升全尺寸电缆空间电荷测量技术及直流局部放电检测技术,完善电缆系统设计选型、试验验证与运行维护的相关规范与标准等。该研究可为我国挤包绝缘高压直流电缆设计、关键材料、装备制造和试验技术等相关方面的研究提供参考。

High voltage direct current （HVDC） extruded cable is one of the key power devices for realizing the flexible interconnection of large power grids, the power transmission with long distance and large capacity, and large-scale utiliza- tion of renewable energy. We review the progress of HVDC extruded cables from aspects including the development of insulating materials, accessory technologies, testing methodologies, cable measuring and detecting techniques as well as main projects worldwide. In particular, we analyze recent studies on DC conductivity and space charge properties of var- ious insulation materials for DC cables, type and prequaliflcation tests of DC cable systems as well as measurement methods of space charge and DC partial discharge on full-size cables. Moreover, we put forward urgent questions need to be solved in HVDC extruded cable technology, for instance, studying DC conductivity and space charge characteristics as well as long-term aging behavior and mechanism of existing insulation, developing new materials for higher voltage DC cables and accessories, optimizing the structural design of cable accessories, improving the space charge measurement and DC partial discharge detection technologies for full-size cables, and revising corresponding standards and regulations for HVDC extruded cable systems. Hopefully, the research will provide a reference for designing, manufacturing, testing, operating, and maintaining of HVDC extruded cables in China.