500 kV交流海底电缆金属护层冲击感应电压研究

Research on Impulse Induced Voltage of Metal Sheath of 500 kV AC Submarine Cable

摘要:

属护层冲击感应电压是高电压、大长度海底电缆安全运行的重要控制条件。采用电磁暂态仿真软件PSCAD/EMTDC，建立了海底电缆金属护层冲击感应电压仿真模型，对电缆长度、侵入波波形、电缆结构参数等对护层冲击感应电压的影响进行了计算分析，并研究分析了金属护层与铠装层分段短接和采用半导电外护套两种方式对限制金属护层冲击感应电压的作用，研究表明：电缆长度、侵入波波形和电缆结构参数对金属护层冲击感应电压有较大的影响；金属护层冲击感应电压随着分段短接点的个数和外护套电导率的增加而减小。

Abstract:

The impulse induced voltage between sheath and armour is the control condition to verify the safe operation of submarine cable with high voltage and large length. The simulation models for impulse induced voltage are built in PSCAD/EMTP. The influence of cable length, intruding surge waveform and cable structure parameters on the induced voltage between sheath and armour are calculated and analyzed. The effects of bondings at intervals between sheath and armour and using a semiconductive oversheath on limiting the induced voltage are analyzed. The research results show that the cable length, intruding surge waveform and cable [JP] structure parameters have an apparent influence on the induced voltage between sheath and armour, and the induced voltage decreases with the increase of the number of bondings and the increase of the conductivity of semiconductive oversheath.