Study On Overvoltage Of 500 KV Overhead Line-AC Submarine Cable

Networking project in hainan is China’s first 500 kv ultra-high voltage,long distance,large capacity of sea-crossing engineering,For 500 kv ac submarine cable transmission system,lightning overvoltage and switching overvoltage are for the insulation of the cable greater threat,it is necessary to research on the content.On the basis of the system data,a simulation model has been developed,which is useful for analyzing the overvoltage and regularities of distribution.On the basis of the structure about submarine cable,the model has been developed.The simulation model has been developed on the condition of lighting overvoltage.The amplitude of lighting overvoltage is 917 kV.Researching the regularities of diatribution about the lighting overvoltage,and the amplitude is on the end submarine cable,which is connected with the length of cable;analyzing the different element which has effect on the amplitude of overvoltage.The simulation model has been developed on the condition of switching overvoltage.The amplitude of switching overvoltage is 786 kV(1.75 p.u).Researching the regularities of diatribution about the switching overvoltage,and the amplitude is far from the operated terminal.