Research On Wind-induced Vibration Response And Practical Design Of 1000kV UHV Transmission Towe

During the past decade,the country’s demand for electric energy increased significantly.Because of its high transmission rate and effective use of transmission corridors,the 1000 kV UHV transmission tower has received wide use.However,with the increase of voltage and span,the transmission tower is more vulnerable to wind damage.In this paper,the three-dimensional component force at the bottom of the transmission frame is measured by high-frequency wind tunnel test,and the aerodynamic coefficient and shape coefficient of different tower sections are calculated.The wind tunnel test data are applied to the prototype structure through finite element simulation to obtain the displacement acceleration time history under different landform and wind direction angles,and then the wind vibration coefficient at the key nodes is obtained.The main research work is as follows:(1)The base force of 1000 kV UHV substation frame is analyzed by high frequency wind tunnel test under three wind fields.The aerodynamic coefficients of different tower sections of transmission tower under different wind directions and wind fields are obtained,and the shape coefficient is calculated.The contribution ratio of aerodynamic characteristics of different tower sections of transmission tower is investigated.(2)The shape coefficient of the whole and segment structure model of the transmission tower is calculated by the results of the calculated aerodynamic coefficient.By comparison,the influence of different wind direction angles and landform on the whole and segment structure model of the transmission tower is judged,and the root cause of the change of shape coefficient caused by different landform is explored.Comparing the shape coefficient of the segment model with the wind resistance of the transmission tower is done to investigate the contribution of the shape coefficient of the segment model to the wind resistance of the transmission tower.Lastly,the shape coefficient calculated from the wind tunnel test is compared to the relevant domestic codes,which gives some recommendations for the transmission tower’s safety and stability,as well as reasonable design parameters.(3)By applying the mathematical relationship to the finite element model of the transmission tower structure,the key position load of the prototype structure is calculated based on the three-dimensional component force of the bottom space of the 1000 kV UHV substation structure obtained from the high-frequency force measurement wind tunnel test.The displacement wind vibration coefficient under the acceleration and displacement response of the tower structure is calculated.As a result,the acceleration wind vibration coefficient is calculated,and the acceleration and displacement responses of the key nodes at different positions are analyzed with respect to the acceleration and displacement coefficient.An investigation is carried out to determine the relative responsiveness of wind vibrations to different landform and wind directions angles.(4)Using the peak factor method and the inertial wind load method,it is possible to calculate the wind vibration coefficients at different heights of the frame and under a variety of landform,and compared the wind vibration coefficients at the key nodes of the transmission frame under a variety of landform.Finally,through the standard comparison,it provides some reference for the design value of wind vibration coefficient of 1000 kV UHV transmission tower.