Case study to estimate the sag in overhead conductors using GPS to observe the effect of span length

Sag of the transmission line mainly depends on the weight of conductor, span length, type, temperature and tension. Weather parameters such as wind and ice have significant effect on the conductor weight and temperature. The present paper is based on the Case study conducted to estimate the sag in overhead conductors using Global Positioning System (GPS) to observe the effect of span length on sag measurement. Various overhead conductors have been considered to analyze the effect of span length on the estimated sag obtained using GPS and compared with physically measured sag. The raw GPS sag measurements of overhead conductor are not so accurate because of various inherent error sources in GPS and thus these observations of GPS measurements are not usable for evaluation of overhead conductor sag directly. Hence Digital Signal Processing (DSP) techniques such as, Bad Data Identificatio/Modification; Least Square Parameter Estimation; Haar Wavelet Transform. are used for error reduction in observed(raw) GPS measurements.