V型绝缘子串在500 kV直线塔中应用普遍，因V型绝缘子串背风侧绝缘子受压，绝缘子损坏或掉线的事故时常发生。通过计算，得出了杆塔Kv值与V型绝缘子串背风侧绝缘子串受力之间的关系。在输电线路设计阶段，通过调整杆塔实际Kv值，使其大于Kv控制值，可以避免V型绝缘子串损坏或掉线事故的发生，对输电线路排杆定位具有参考价值。

V-type insulator string has been widely applied in 500 kV straight line tower. However, damaged and dropping accident of insulator string occurred frequently, because of the compression on V-type insulator string at leeward side. The relationship between Kv value of transmission tower and V-type insulator string loadcarrying capability was obtained by means of computation. The actual Kv value could be adjusted more than the control value in the design stage of transmission lines, in order to avoid the damaged and dropping accident of insulator string, which could provide guiding significance to the pole position for transmission lines.