Research of the lightning protection performance for 220 kV double-circuit transmission line

By use of ATP-EMTP software, built the simulation of 220kV double-circuit transmission line. Then discussed the factors that affect the lightning performance of each tower, such as the height of tower, grounding resistance, insulation configurations, grounding wires and so on. The simulation results show that the tower height has a great impact on the lightning performance of double-circuit, so we should minimize tower height considering the actual condition; reduce the ground resistance can improve the lightning impulse withstand level effectively, especially in the low resistance. For tension tower, using an unbalanced insulation is the most effective way to reducing double tripping. For straight-line tower, increasing the piece of glass insulator is also an effective way to reducing double tripping rate. If the conditions allow, a coupling grounding wire can reduce the double-line trip obviously by use of its shunt and coupling function.