Study on Improving Lightning Withstand Level of 330 kV Transmission Line with Line Arrester

Study on adopting surge arrester to increase lightning withstand level of 330 kV EHV transmission line by electromagnetic transient program(ATP-EMTP) is conducted.The impact of some factors,such as low-frequency grounding resistance of tower,span of line and number of arresters,on lightning withstand level are analyzed.The lightning discharge energy absorbed by arrester is also considered.The results show that the lightning withstand level can effectively improved by arrester.The grounding resistance has great impact on lightning withstand level and the span of line have some influence on lightning withstand level.The protection range of surge arrester is small.The surge arresters can only protect the tower where the surge arresters install on.Therefore,the suitable surge arresters erection scheme shall be selected based on the actual situation for reducing cost.