Analysis of DC ice-melting temperature rise characteristics and ice-shedding dynamic response of old OPGW lines

OPGW has been widely used in the power grid. DC ice melting is one of the effective measures to prevent OPGW from icing accidents. Taking the old OPGW-48Bl-90 ground wire as the research object, the DC ice-melting entity model of OPGW under different operating conditions is established, and the temperature rise characteristics of OPGW during the DC ice-melting process are calculated. The influence of different ice thicknesses and external wind speed on the temperature distribution of OPGW is explored. The temperature change process of the OPGW center point is analyzed, and the OPGW temperature at ice-shedding time is obtained as the initial condition. At the same time, the influence of different ice thicknesses and external wind speeds on the dynamic response of OPGW at ice-shedding time is explored, and the dynamic response of old OPGW DC ice-shedding is analyzed. The results show that the radial temperature distribution of the old OPGW DC ice melting process is not uniform. The influence of ambient wind speed on temperature is nonlinear. The ambient wind speed will affect the temperature rise speed and ice melting time during the DC ice melting process of the ground wire; the higher the ice-melting current and the thicker the icing thickness, the higher the internal temperature of the ground wire at the ice-shedding time, and the larger the vertical maximum displacement of the OPGW midpoint. The vertical maximum vibration displacement of the OPGW midpoint increases with the increase of ice thickness.