Research On Dynamic Response Of Subspan Oscillation By Energy Method And Oscillator Model Method

At present,the national Power Grid Corp has built four to five straight the nine UHV project.This thing has played an important role in steady growth,structural adjustment,governance.The construction of the "three pay six straight nine UHV project will also be completed and put into operation in the" 13 th Five-Year "period.For the UHV transmission line has been completed,many lines had serious subspan oscillation found in completion inspection.Subspan oscillation is the vibration form of UHV transmission line characteristic of the multi splitting.Time span oscillation will lead wire collision or damage and the spacer bar will also loose or fall off so as to affect the life and safety of the wire.So it is necessary to conduct in-depth study of subspan oscillation.This paper did subspan oscillation study more deeply and the main contents are as follows:1.Aerodynamic model study.The improved drag coefficient and lift coefficient model are presented.Based on the drag coefficient of fluent simulation,The resistance coefficient formula is fitted and compared with the traditional polynomial aerodynamic model and the exponential aerodynamic model from two aspects of physical meaning and accuracy.Finally,the accurate aerodynamic force fitting formula is selected and used to solve the aerodynamic force of the conductor.2.Subspan oscillation energy method research.A new index aerodynamic load model is derived for single and double degree of freedom subspan oscillation energy formula.After comparing with the current subspan oscillation energy method formula,its reliability was verified.An improved energy formula for the wind angle of attack is obtained.In addition,the energy method formulas in this effect of split spacing,wind attack angle and other factors on the time span is also discussed based on shock response amplitude.3.Study of dynamic stiffness oscillator model.The characteristics of structural dynamics and subspan oscillation based on itself,with more sophisticated subspan oscillation oscillator model as the research object,A detailed definition of the equivalent mass,equivalent dynamic stiffness and dynamic equivalent load,using MATLAB programming and iteration methods with high efficiency,response simulation of subspan oscillation trajectory,displacement,speed,tension etc.The dynamic stiffness of oscillator based on the model,discusses the influence the split spacing,span length,wind attack angle,wind speed and wire tension on the vertical and horizontal subspan oscillation amplitude response.4.The development and application of subspan oscillation calculation software.MATLAB and GUI software package based on the preparation of subspan oscillation response calculation software.And the selection of 30 kinds of wire models commonly used,calculate and compare the different types of conductors subspan oscillation response characteristics of the use of software.The empirical formula of vertical amplitude for different types of wires is fitted,and the semi empirical and semi empirical formulas of different types of energy are obtained.