The Simulation and Analysis of Iced Conductor Forced by Time-Varying Aerodynamic

Galloping of an iced transmission line is characterized by high amplitude, low frequency, self-excited vibration produced by a steady side wind. It is a dangerous phenomenon that seriously threatens the security of power systems. In this paper, the finite element method is utilized and one kind of point element having concentrated mass is used to simulate the inertia and eccentricity of the ice which is rigidly coupled to the conductor. At each ends of the span, the conductor's interactions with a support tower are modeled through connecting insulator and the conductor at the suspension point where all the translational and the torsional degrees are coupled. The insulator is a rigid link connected rotatably to the tower. The influence of adjacent spans is considered by connecting each end of the span with a spring has stiffness of the equivalent stiffness of the each adjacent span. The current configuration of the conductor is obtained before the dynamic simulation and time-varying aerodynamics and gravity of the system are applied at each node during the simulation. A example high voltage transmission line is studied and the phenomenon of galloping has been illustrated at certain wind speed and ice-thickness.