Simulation Research On Blasting And Deicing Of Transmission Lines Under Wind Load

The problem of icing on transmission lines has always been a major problem in the operation of power grids.The icing of the line will cause serious disaster to the whole transmission system.In order to solve the problem of grid paralysis caused by the ice sheet of the wire,some scholars have proposed blasting de-icing.The research on wire deicing becomes very important.With the increasing maturity of blasting deicing methods,for the sake of make the blasting deicing method more perfect It is very necessary to study the dynamic response of the wire after blasting de-icing of ice-clad conductors under the action of wind load.Firstly,this paper simulates the shape-finding of the transmission line,calculates the coordinates of each node of the wire through the Matlab software,and completes the shapefinding of the wires in ABAQUS.In order to get the burst impact load,the dynamical simulation software AUTODYN was used to simulate the detonating cord explosion,and the blast shock wave pressure curves under different spacing between the detonating cord and the wire were obtained.In the deicing simulation of ice-covered wires,ABAQUS subroutine was used to add the acceleration deicing criterion to the simulation process,Thus,the simulation purpose of ice falling off the wire is achieved,and the acceleration de-icing criterion of circular uniform and crescent ice was deduced.The aerodynamic analysis of crescent-shaped ice-covered conductance was carried out by FLUENT software,and the variation of lift and drag coefficients of ice-covered conductance under different wind attack angles was studied.The obtained aerodynamic parameters were converted into constant wind load,and the dynamic response of blasting de-icing of ice-covered wire under constant wind load was analyzed and studied by ABAQUS software.We can know that,As the thickness of the icing increases,the drag value in the aerodynamic parameters increases,but its lift value is basically unchanged.In blasting de-icing simulation,the wind speed will affect the selection of blasting amount of ice-covered wire in blasting de-icing.The greater the wind speed,the smaller the allowed blasting amount in the safety code.In order to simulate the pulsation wind speed time,a pulsation wind time-time solution based on linear filtering is written by MATLAB.The numerical simulation of the wind speed time range of various points on a trans-transmission line road is obtained,The time curve of pulsating wind under different wind direction is obtained The power spectral density is compared.The results show that they are basically the same.Wind speed time history simulation of single span transmission line.The results show that the fluctuating wind speed time history curves of up and down wind direction and vertical wind direction are basically the same at each frequency;we can use the wind speed we get to apply it to the wire.The wind vibration simulation and blasting de-icing response analysis were carried out on the ice-covered wire respectively,We can see that the pulsating wind causes the transverse swing of the wire to vary greatly.It can also be seen that as the wind speed increases,the frequency of the time history curve between the jump height and the lateral swing amplitude of the ice-coated wire decreases significantly.In blasting deicing,comparing the response peaks under the two conditions of rime icing and rime icing,it is found that the amplitude of rime icing with wind load is greater.The blasting and deicing of the conductor under the action of pulsating wind will not only increase the stress in the conductor,but also increase the fluctuation of the stress in the conductor.When the wind speed is higher,the stress of the wire is greater the influence of deicing.In the actual de-icing process,the selection of blasting quantity should be carefully considered for the rime icing under high wind speed,and blasting de-icing is not suitable when the wind speed reaches a certain level.