高电压技术2017，Vol.43Issue(11)：3514-3520,7.DOI:10.13336/j.1003-6520.hve.20171031004
基于VSC-HVDC输电的直流电缆护套过电压建模
Modeling of DC Cable Sheath Over-voltage Based on the VSC-HVDC Transmission
摘要
Abstract
Significant over-voltage induced along the protecting sheath of a direct current cable used in the voltage-sourced converter-based high voltage direct current (VSC-HVDC) transmission application can lead to the cable breakdown.Consequently,we established a mathematical model of a direct current cable,and put forward calculation methods of each parameter based on admittance matrix.Meanwhile,taking the underground direct current cable of Xiamen VSC-HVDC scheme as a reference for study,we simulated the cable using a cascade model,and simulated the voltage breakdown behavior by using a simplified AC discharging circuit.Simulation results show that,for a breakdown of the cable's main insulation,over-voltage induced along metal sheath of the cable possesses high-frequency voltage,the peak value can be as high as several kV and duration can last for up to 2～3 milliseconds.The induced over-voltage stress along the metal sheath increases when the faulty location is close to the converter stations.Therefore,protections have to be taken into consideration during the design of HVDC cables so that its shielding layer can avoid being damaged even if a high-frequency over-voltage is induced along the sheath layer of the cable.关键词
VSC-HVDC/直流电缆/陆缆/主绝缘击穿/护套/过电压/数学模型Key words
voltage-sourced converter-based high voltage direct current/direct current cable/underground cable/main insulation breakdown/sheath/over-voltage/mathematical model引用本文复制引用
曹均正,张轶..基于VSC-HVDC输电的直流电缆护套过电压建模[J].高电压技术,2017,43(11):3514-3520,7.基金项目
国家电网公司科技项目(交联聚乙烯(XLPE)直流电缆及附件关键技术研究).Project supported by Science and Technology Project of SGCC(Research on Key Technologies for XLPE Direct Current Cable and Accessories). （交联聚乙烯(XLPE）
