220kV线路典型复合绝缘子的雷电冲击特性研究

Research of Lightning Impulse Characteristics of Typical Composite Insulator in 220 kV Line

为有效提高我国220 kV复合绝缘子线路的耐雷水平，降低多雷区雷击跳闸率，采用标准雷电冲击波对不同结构高度的220 kV复合绝缘子进行雷电冲击试验。在建立模拟杆塔模型的基础上，通过雷电冲击试验，对模拟杆塔下相复合绝缘子与玻璃绝缘子的雷电冲击电压进行对比分析。结果表明：复合绝缘子结构高度每增加150 mm，雷电冲击电压增加70～91 kV；相同结构高度的复合绝缘子，下相的雷电冲击电压最高，中相次之，上相最低；干弧距离相等的220 kV玻璃绝缘子的U50雷电冲击电压比复合绝缘子高93～232 kV。

To improve the lightning withstand level of China＇s 220 kV composite insulator line and reduce lightning trip-out rate, the standard lightning impulse wave was used to launch lightning impulse test on the 220 kV composite insulator with different structure height. Based on the simulation of tower model, the lightning impulse voltages of bottom phase composites insulator of simulate tower and glass insulator were compared by lightning impulse test. The results show that the structure height of composite insula-tor increases 150 mm for each, the lightning impulse voltage increases 70~91 kV. For the composite insu-lator with the same dry arc distance, the lightning impulse voltage of the bottom phase is the highest, the middle phase takes the second place, and the upper phase is the lowest. The U50 impulse voltage of the 220 kV glass insulator with the same dry arc distance is about 93~232 kV higher than that of the composite insulator.