LAUSR

Transmission line sag and voltage are key information to reflect the real-time operation state of power grid. Contactless measurement method has great advantages of no electrical contact, flexibility and mobility, but it is also vulnerable to environmental changes. In this article, a novel overhead transmission line contactless sag and voltage monitoring method is proposed, which only needs a simple potential measurement array and can apply to dynamic conductor measurement. The electrostatic coupling model between the transmission lines and the measuring points is established. The sag and voltage inversion calculation model is proposed and the ill-posed problem is solved. The measurement array and the data acquisition method are designed. The equivalent measurement area (EMA) is determined considering the difference between 3-D model and 2-D model of overhead line. Finally, the effectiveness of the proposed method is verified by single-circuit transmission line simulation and scale-down experiment.