| As the most common form of wind-induced vibration,aeolian vibration may lead to fatigue damage of transmission lines,towers and fittings,it seriously affect the working life and reliability of transmission lines.This paper uses dynamic method to calculate aeolian vibration of transmission lines,the research object is aeolian vibration of a conductor span with dampers,the main work of this paper can be concluded as follows:Firstly,this paper summarizes the research status about aeolian vibration of transmission line-dampers system.Secondly,the mechanical model and dynamic equation of transmission line-dampers system are established.The transmission lines are simplified as hinged beam at both ends with small stiffness;the dampers are simplified as spring mass oscillator system by lumped mass model and the expression of the exciting force of the breeze is given.Finally,the mechanical model of transmission line-dampers system is obtained,the dynamic equation of system is derived from this model.The breeze excitation force,the force of dampers and the self damping coefficient of transmission lines needed to solve the equation are also given.Thirdly,dynamic equation of transmission line-dampers system is solved by MATLAB program based on the finite difference method of four order accuracy.The vibration modes of transmission lines before and after installation of dampers are calculated and analyzed,and two kinds of dynamic bending strain algorithms are given;the similarities and differences of calculation results between dynamic method and energy balance method after installation of dampers are also analyzed.Finally,different types of dampers,installation position and installation number are calculated by the self compiled MATLAB program.The causes of peak value of amplitude and dynamic bending strain curve are analyzed,the vibration suppression of dampers has been studied. |
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