## 5 Discussion  
This paper established a continuous multi-span overhead transmission line model using finite element numerical simulation techniques to investigate the dynamic response of transmission lines during ice shedding under strong wind conditions. Furthermore, some complex factors were analyzed, such as high wind speeds, ice shapes, and wind angles on the bounce process of transmission lines, aiming to explore the risks posed by the ice shedding bounce of power lines under complex conditions.  
1. The calculation of lift and drag forces on the iced conductor is fundamental for understanding the dynamic response of conductors during ice shedding under strong wind conditions. Additionally, the stability of conductor galloping was assessed based on [PERSON]'s vertical vibration theory and [PERSON]'s torsional vibration theory, both of which rely on the concept of negative damping. In this study, finite element  
Figure 7: Effect of wind speed on ice shedding bouncing process. (**a**) round-shaped; (**b**) crescent-shaped; (**c**) elliptical-shaped; (**d**) fan-shaped; (**e**) D-shaped.  
methods were utilized to compute the lift and drag forces on iced conductors under different conditions. It was found that fan-shaped and D-shaped ice covers exhibited sharp changes in curvature and planarity, with the strongest hindrance to airflow occurring at a 180\({}^{\circ}\) attack angle, resulting in the highest drag force on iced conductors. At this angle, the drag force on D-shaped ice covers could exceed ten times that of the elliptical and crescent-shaped samples. The unique shape of D-shaped icing resulted in positive lift between 0-180\({}^{\circ}\), peaking around 135\({}^{\circ}\). These results closely match those observed in wind tunnel experiments [24]. At a wind angle of 225\({}^{\circ}\), the airflow increased the directional additional load by one-third, leading to an increase in the conductor's elastic potential energy.
2. Due to variations in meteorological conditions and conductor characteristics, natural icing can exhibit significant differences in morphology, resulting in shapes such as circular, crescent, D-shaped, fan-shaped, and elliptical. Under the same icing mass (volume) and wind speed conditions, the dynamic response process of conductors after ice shedding becomes highly complex. Under the combined influence of airflow and icing, conductors possess both longitudinal and lateral elastic potential energy. Generally, iced conductors with circular, crescent, and elliptical shapes have smooth outer curves, resulting in minimal lateral displacement under wind forces. At a wind speed of 10 m/s, their maximum vertical bounce heights were 9.94 m, 10.6 m, and 10.07 m, respectively. The maximum lateral bounce heights were only 0.31 m, 1.16 m, and 1.36 m, indicating minimal differences from the no-wind condition. The maximum longitudinal displacement was approximately 1.62 times the difference in longitudinal positions before and after ice shedding, slightly smaller than the value of 1.8 reported in the literature [14], but with minimal differences from the literature [25]. Except for the crescent-shaped ice cover at a 45\({}^{\circ}\) wind angle, corresponding to the minimum bounce condition, the maximum lateral displacement was approximately 1.56 times the difference in lateral positions before and after ice shedding.  
For fan-shaped and D-shaped icing, the airflow resistance significantly increased at a 180\({}^{\circ}\) attack angle. At a wind speed of 10 m/s, their maximum vertical bounce heights were 0.79 m and 9.32 m, respectively, while the maximum lateral bounce heights were 11.7 m and 6.65 m. At a wind speed of 20 m/s, the maximum lateral bounce heights reached 28.5 m and 20.85 m, respectively. The maximum lateral displacement was approximately 1.55 times the difference in lateral positions before and after ice shedding. The bounce distances exceeded the lateral spacing between transmission lines, greatly increasing the possibility of interphase discharge.