The Research On The DC Ice-melting Technology Of Transmission Lines

With the increase in extreme weather, transmission line has been a serious threat to the safe operation of power grid. Now there are several methods of ice melting in power system, the most widely method is melting ice by using three-phase short-circuit-current. In view of the superiority of direct current melting ice, it has been more and more attractive. For high voltage AC transmission line and DC transmission lines, this paper will discuss the DC melting ice method respectively. For high voltage AC transmission line, the paper analyzes its principle of melting ice, presents design of DC-melting ice, and according to the design parameters simulate the design under the environment of PSCAD/EMTDC to verify its feasibility. For DC transmission lines, this paper presents back to back ice-melting method and parallel mode bipolar ice-melting method. Refer to the standard model of HVDC, this paper analyzes various operating mode control strategy and simulates back to back ice-melting method and parallel mode bipolar ice-melting method under the environment of PSCAD/EMTDC to get steady state and transient parameters under different operating modes. The results show that this design is effective in ice-melting.Also we can get the conclusion that for each ice-melting method, it is not necessary to increase the reactive power compensation and filtering devices in the converter station.