Research On Mechanism Of Rain-wind Induced Vibration On High-voltage Transmission Lines

In the wind and rain loads, high-voltage transmission lines will cause a substantial stable vibration, which is called rain-wind induced vibration(RWIV).When the RWIV occurs, substantial vibration will accelerate the fatigue wear of fittings. Even more seriously, it can make the overall tower-line system collapsed, causing incalculable damage. To avoid losses and prevent the occurrence of such disasters, it is necessary to study the mechanism of RWIV.Firstly, based on the deep analysis and research on the transmission lines in the rain vibration phenomena, as well as the reference to the research results of the RWIV on cables, this paper proposes that the RWIV on transmission lines is a coupled vibration of cable type RWIV and the corona shock. Combined with wind, rain load characteristics and force of lead under the wind and rain, the mathematical model of the transmission lines of RWIV and its transmission lines is established. Secondly, this paper simulates the above model using Fluent software. The results show that the lift coefficient and drag coefficient are high-frequency coefficients, and the mean values are more meaningful for the study of RWIV. The upper rain-line is the main reason for the occurrence of RWIV on transmission lines. Compared with cables, transmission line is more susceptible. According to the curve showing that the aerodynamic coefficient changes with the upper rain-line position, this paper finds an approximate range of danger zone of upper rain-line position, which could cause RWIV. Finally, in order to further analyze the actual vibration of transmission line and compare with the simulation data, this paper builds a RWIV exciting bench. The bench can be divided into five parts:the wind load part, the rain load part, transmission lines holder, sensor part, and the support platform part. Experimental methods and planning were presented preliminarily.In this paper, only the high-voltage transmission lines induced mechanism was discussed. Found that transmission lines are more susceptible to wind and rain loads, predicted the ’danger zone’ which may lead transmission lines vibration and conducted the RWIV simulation. It is worth noting that, the induce mechanism of RWIV on transmission lines is very complex, the subsequent need further study.