Experimental study on dynamic responses of transmission lines caused by#br#
ice shedding
Li Hongnan1,2 Wu Yuyan1
1. State Key Laboratory of Coastal and Offshore Eilgineering, Dalian University of Technology, Dalian 116024, China;
2. Shenyang Jianzhu University, Shenyang 110168, China
Abstract：Ice shedding from electrical transmission lines can easily lead to flashover between the conductors and the damage of fittings, posing a threat to the security of electrical power system. The study on the dynamic responses of conductors caused by ice shedding can provide valid references to the power grid design against ice disaster. In this work, ice-shedding and rebound experiments on a conductor with an isolated span of 50 m were conducted. In the tests, the masses of accreted ice were simulated by lumped loads hanging on the conductor and the ice shedding sequence and speed were controlled by the time relay. The tensile forces at both ends and the rebound height of mid-span of the conductor were measured by varying the thickness of icing, ice-shedding ratio, ice-shedding position, ice-shedding sequence and speed, and then verified by a series of numerical simulations using ANSYS software. The experimental results showed that the maximum dynamic tensile forces after ice shedding was not much different from the maximum static tension forces; the maximum rebound height of mid-span conductor was caused by the ice-shedding falling from the middle to both sides; when the ice fell rapidly from the two sides of the conductor to the middle, the rebound height was the minimum.
