Analytical Model of Rain-Wind Induced Vibration of High-Voltage Transmission Line

Chao Zhou,Yibing Liu

doi:10.1155/2014/638653

Abstract

Under rainfall conditions, rain-wind induced vibration occurs on high-voltage transmission line occasionally. This phenomenon is caused by raindrops hitting the high-voltage conductor with a certain velocity and suspends to the bottom surface of the high-voltage conductor. By action of wind velocity and high-voltage conductor's motion, some suspended raindrops will be blown away or shaken off. The remaining water may be reformed as upper rivulet and lower rivulet. Like the effect of icing galloping, this type of vibration can cause metal fatigue on fittings and towers, while its mechanism remains unknown. The objective of this paper is to validate an analytical model of rain-wind induced vibration of the high-voltage transmission line and to investigate the effect of wind velocity, rivulet motion, raindrop velocity, and time varying mass on the vibration amplitude. Taking Tuo-chang transmission line as an example, the analytical model is solved by Galerkin weighted residual method and central difference method. The numerical results are in agreement with the experimental data available in the literature. The analytical model enables more comprehensive understanding of the rain-wind induced vibration mechanism.

Highlights

The planned ultra-high-voltage transmission tower-lines will be across the terrain, wet, and rainy regions of southwest China; one of the key problems is how to ensure secure and stable operation of the high-voltage transmission towerlines [1]
To start with the simplest case, we investigate the dynamic behavior of the high-voltage conductor with fixed upper rivulet and time-varying mass by using the derived formulation
For the aims of revealing mechanism of rain-wind induced vibration of high-voltage transmission lines, taking the raindrop velocity and time-varying mass into consideration, an analytical model for describing rain-wind induced vibration of high-voltage transmission line is introduced in this paper

Summary

Introduction

The planned ultra-high-voltage transmission tower-lines will be across the terrain, wet, and rainy regions of southwest China; one of the key problems is how to ensure secure and stable operation of the high-voltage transmission towerlines [1]. Under rain-wind conditions, raindrops hitting the high-voltage transmission line may form rivulets on the surface of the high-voltage conductor. The asymmetric crosssection of the high-voltage conductor, motion of the rivulets, and time varying-mass of the whole system maybe are the main cause of rain-wind induced vibration on high-voltage transmission lines. Like the effect of icing galloping, this phenomenon can result in fatigue fractures of high-voltage conductor and fatigue failures of spacers and insulators and threaten the safety and serviceability of the high-voltage transmission tower-lines [2,3,4]. The results show that rain loading coupling with wind force have a more distinct effect on dynamic characteristics of the high-voltage transmission tower-lines system than that of only acting by wind force, and rain loading plays an indispensable role in rain-wind induced vibration of the high-voltage conductor. Zhou et al [3, 4, 10, 11] investigates the effects of ionic wind, rainfalls, wind

Raindrop

Analytical Model of Rain-Wind Induced Vibration on the High-Voltage Conductor

Numerical Computations and Discussion

Conclusions