避雷线架设方式对自耦变压器供电方式接触网反击耐雷性能的影响

Influence of the Construction Modes of Lightning Conductor on the Lightning Protection Performance of Back Striking in the Contact Network Under Auto-transformer Power Supply Mode

我国接触网没有直击雷防护措施,耐雷水平低,架设避雷线可以有效提高接触网耐雷水平。为此,利用ATP-EMTP软件建立了雷击接触网模型,分析了保护线升高(方案1)和单独架设避雷线(方案2)这2种方案的雷电防护效果,同时研究了2种方案的支柱分流系数、避雷线分流系数以及它们之间的耦合关系,从而确定其改善接触网防雷机理。研究结果表明:方案1的耐雷水平提高约20%,方案2的耐雷水平提高约40%;支柱分流系数可达到约80%,远大于保护线和避雷线分流系数;接触网改造后,方案1支柱分流系数能够降低约2%,方案2支柱分流系数能够降低约4%,从而有效降低了支柱顶端电位;接触网改造后,方案1耦合系数能够提高约10%,而方案2耦合系数能够提高到50%以上,2种方案均降低了绝缘子两端电压,从而提高了耐雷水平。

There are no direct lightning protection measures in the contact network and the lightning withstand level of the contact network is low. Erecting lightning conductors is an effective measure to protect the contact network from the direct lightning. We adopted the ATP-EMTP software to build a lightning contact network model and analyze the lightning performance of two different schemes including the elevated protection wire and erecting the lightning conductor. At the same time, the shunt coefficient and coupling coefficient were also analyzed to explain the mechanism of the lightning. The research shows that the lightning performance of the first scheme increases by about 20% and the second is about 40%. The shunt coefficient of the pillar is about 80% which is much larger than that of protection wire and lightning conductor. The shunt coefficient of the pillar decrease by about 2% and the second decrease by about 4%. The two schemes can effectively reduce the potential of the pillar. The coupling coefficient of the first scheme increase by about 10% and the second scheme is about 50%. The two schemes reduce the voltage of the insulator so as to improve the lightning with- stand level of the contact network.