Simulation study on lightning-induced multi-circuit/phase tripping and multi-point lightning effects in transmission lines

In this paper, the electromagnetic transient simulation model of 110 kV double-circuit transmission line on the same tower is established based on ATP-EMTP, and the lightning resistance performance under multi-circuit multi-phase lightning strike and the influence of multi-ground-point lightning on tripping characteristics are studied. By improving the electrogeometric model and the calculation method of the regulation method, it is found that there is a high risk of shielding failure / counterattack in 4 of the 11 towers in the whole line, and the risk can be effectively alleviated by reducing the grounding resistance. The back striking lightning withstand level of 1-6 phase tripping is quantitatively analyzed. A multi-ground-point lightning strike model is constructed. The results show that when the two-phase lightning strike is injected at a 10 μs interval, the traveling wave phase can locate the lightning point, and the time difference reflects the lightning bifurcation interval. The current waveform of the tripping phase shows a truncation characteristic of 0.5μs half-peak, which can be used as a double tripping criterion. The research results provide a theoretical basis for line protection and co-jump risk assessment under multi-ground-point lightning strikes.