中文摘要：

为论证直流输电线路工作电压对其绕击耐雷性能的影响,并评估在避雷线上安装水平侧针和减小保护角两种防护措施的防护性能,针对±500kV直流输电线路G4—40型杆塔开展了1：40的雷电绕击模拟试验研究。试验结果表明：在极导线施加正极性直流工作电压后,模拟输电线路的绕击空间明显增大,直流工作电压增强了迎面流注的起始能力是造成该绕击空间增大的主要原因;于避雷线上安装水平侧针可降低绕击导线的概率,但其单针沿档距方向保护范围有限;减小线路保护角可于全档距内降低绕击概率,其效果优于水平侧针。

英文摘要：

In order to verify the suppose that the operating voltage of DC transmission line will affect its lightning shielding performance,and to estimate the protective performance of the side needle and negative shielding angle,we experimentally studied the G4—40 tower of 500 kV DC transmission line by simulation.The results indicate that the shielding failure space amplifies when applying a positive voltage on the transmission line,and the propagation capability of upward streamer because of positive applied voltage is the critical reason for the enlargement of the shielding failure space.Moreover,the side needle can reduce the strike probability in a limit region of line span.In contrast,the lightning shielding performance of negative shielding angle is superior to the side needle.