Back Flashover Protection Performance Analysis of 220kV Double Circuit Transmission Line

Because of the larger trigger lighting area, 220 kV double circuit transmission line is more vulnerable by lightning, and shielding failure and back flashover are more prominent. Therefore, the accurate assessment of the lightning protection performance of 220 kV double circuit transmission line is crucial to ensure the security and stability of the transmission network. This paper presents the main result of a back flashover simulation model for double circuit transmission line using Electromagnetic Transient Program (EMTP), this model include lighting source model, transmission line model, tower impulse current response model, insulator string flashover model, footing impedance model and induced voltage component model. Based on this model, this paper do some simulation to research in the influence that the tower height, footing impedance, soil resistivity and insulation strength have on the lighting protection performance of the 220 kV double circuit transmission line.