冲击电晕对特高压输电线路绕击耐雷水平的影响分析

Analysis of Lightning Shielding Failure Proof Level of UHV Transmission Lines Considering Corona Influences

基于ATP-EMTP建立了考虑电晕影响的UHVAC输电线路的雷电绕击耐雷水平分析模型。在验证所建模型的合理有效性之后分析了电晕对我国特高压试验示范工程输电线路初步设计的4种杆塔模型线路的耐雷水平的影响。仿真分析表明,冲击电晕对绕击耐雷水平影响很大,而且线路电压等级越高,这种影响越大。对于1000kV特高压线路,考虑电晕影响后线路绕击耐雷水平升高了约40%。此外,还基于杆塔模型为ZMP2的特高压线路,分析了线路工作电压对绕击耐雷水平的影响。在考虑电晕影响的情况下,考虑工作电压时的耐雷水平比不考虑工作电压时低5.3kA;而对于500kV线路,考虑工作电压比不考虑工作电压的耐雷水平只低2.4kA。可见导线工作电压对特高压线路的耐雷水平影响更大。

An ATP-EMTP model for analyzing the lightning shielding failure proof levels of UHV transmission lines is presented in this paper. The rationality and availability of the proposed model was validated firstly. Then, the model was applied to the preliminary designed UHVAC transmission lines with four types of towers of the Chinese UHVAC demonstrating project to analyze the influence of corona on their lightning shielding failure proof levels. Conclusions are drawn through analyzing the simulation results. Impulse corona has an important influence on the lightning shielding failure proof level. Further more, the influence of corona increases when the voltage level is increased. The lightning shielding failure proof level of 1000 kV transmission line increases about 40% when corona influence is under consideration. In addition, the influence of operating voltage on the lightning shielding failure proof levels was also analyzed based on the UHVAC transmission lines with ZMP2 type tower. When the corona influence is considered, the shielding failure proof level with considering the operating voltage is about 5.3 kA lower than that without considering the voltage. However, concerning with 500 kV transmission line, the difference is only 2.4 kA. It is shown that operating voltage has more visible influence on the UHV transmission line lightning shielding failure proof level.