挤包绝缘高压直流电缆应用现状与研究展望

挤包绝缘高压直流电缆已成为远距离、大容量输电线路建设的主要装备之一，现阶段广泛应用的挤包绝缘直流电缆以交联聚乙烯(XLPE)绝缘为主。针对XLPE绝缘高压直流电缆研发和应用中的绝缘空间电荷特性、副产物脱气等主要问题进行全面综述，指出在工业化生产方式下，超纯净体系XLPE绝缘材料是目前用来缓解空间电荷问题和实现电缆批量化生产更为可行的技术方案，对于副产物脱气问题的研究需结合小样测试结果，向长距离批量化电缆生产的脱气工艺控制进行扩展。结合现有国内外已投运和正在规划的挤包绝缘高压直流电缆典型工程，指出未来应侧重于在提高绝缘材料电气绝缘水平的基础上，使挤包绝缘直流电缆向更高电压等级发展，并同时通过提高电缆最高允许运行温度实现更大的传输容量。此外，从提高生产效率和利于回收利用的角度考虑，可加强热塑性绝缘材料在挤包绝缘高压直流电缆中的应用研究。

Application Status and Research Prospects of HVDC Extruded Cables

HVDC extruded cable is one of the key facilities for long-distance and large-capacity power transmission lines.The currently widely used DC extruded cable is mostly insulated with crosslinked polyethylene(XLPE).An investigation is conducted on the HVDC XLPE insulated cable in terms of space charge and byproducts degassing.It is concluded that the ultra-pure XLPE material is currently the most feasible way to mitigate the space charge problem and manufacture extruded HVDC cable for large batches.The research on byproducts degassing problem should be based on the testing results of mini-samples to guide the degassing process for long distance and batch production of cables.Based on the extruded HVDC cable projects which have been put into operation or are under design both in China and abroad,it is proposed that future development of DC extruded cables should focus on improving the electrical insulation level of the insulation materials with a higher the operating voltage.Meanwhile,the allowable operation temperature of cables should be elevated to realize a larger transmission capacity.Besides,from the perspective of improving productive efficiency and recycling,it is suggested that the research on application of thermoplasticity insulation material in extruded HVDC cables should be enhanced.