Dynamic Response of Tower-Line System Induced by Insulator Breakage Considering the Collision between the Conductor and the Ground Surface

AbstractInsulator fatigue, lighting strike, or flashover could result in the breakage of insulator strings. Insulator breakage can cause conductor impingement on the ground, which is a threat to the safe operation of a transmission line. To study the influence of this accident on the dynamic responses of a tower-line system, this paper proposes a method to simulate the impingement between the ground and a conductor, and then a finite element model (FEM) of a transmission tower-line system with four towers and five-span lines is established. Several cases are simulated to investigate the impingement between the conductor and the ground and its effect on the dynamic responses of the tower-line system after insulator breakage. The results show that the impingement decreases the vibration of the tower-line system. The traditional methods, neglecting the impingement between the conductor and the ground, overestimate the response of the structure, and the results thus do not accord with the actual situation. Therefore, it is necessary to consider the effect of the impingement between the conductor and the ground surface to better estimate the dynamic response of the tower-line system.