Determination the conductor sag according to the period of own harmonic oscillations

Abstract

The article substantiates the relevance of the inspection of overhead power lines by determining the mechanical loads of the conductors. The conductor sways under the action of external loads and variable internal mechanical loads. The conductor behaves in span like a pendulum. A model of the harmonic oscillations of the conductor in flight is derived to assess the mechanical loads of the conductor overhead power lines. This mathematical model is based on mathematical models of a flexible thread and a model of a physical pendulum. A conductor is a physical pendulum, where the conductor acts as the body, and in the role of the fixed axis of rotation, a straight line passing through the suspension points of the conductor. The article briefly describes an algorithm for calculating the conductor sag for the case when the conductor suspension points are at the same height. The results obtained using the developed model for calculating the sag of the conductor by its period are compared with the available experimental data. Experimental equipment is described. The error of the method is estimated.

A survey of sag monitoring methods for power grid transmission lines

“…In [115], the authors treated the conductor as a physical pendulum around the straight line between the two support towers and derived the relationship between the sag and the period of swing as $$$$\begin{equation} S=0.31T^2 \end{equation}$$$$where T is the period of the swing or the oscillation period. Thus, the sag can be calculated by measuring the natural harmonic vibration of the conductor hanging in a span with supports at the same heights.…”

“…In [115], the authors treated the conductor as a physical pendulum around the straight line between the two support towers and derived the relationship between the sag and the period of swing as…”