Research On Dynamic Characteristics Of Stockbridge Dampers

With the effect of wind,the phenomenon of aeolian vibration is frequently occurred in overhead transmission lines.It may cause the break of transmission lines and even the damage of electric power towers and armour clamps.Therefore,it is necessary to take effective measures to prevent vibration.At present,the lack of research on damper dynamic characteristics leads to a general problem in their performance interiorly.Some effective and systematic theoretical research and computer simulation research are needed therefore.In this paper,two kinds of mathematical models and a finite element model in ANSYS are established to study the frequency characteristics,power characteristics and damping characteristics of dampers.The conclusions can provide reference for the improvement of their structure design and performance.Firstly,the paper summarizes the research status about aeolian vibration prevention and damper dynamic characteristics.The mechanism of aeolian vibration in lines is described and some common types of dampers and theirs development process are introduced in detail.Secondly,the distributed mass models of FD,FR and FDZ dampers are established and the lumped mass models are further simplified.According to the mathematical models,some equations of motion are listed and the method for calculating natural frequencies of each model is further derived.In addition,a finite element model is also established in ANSYS to carry out modal analysis.Thirdly,two mathematical models and the finite element model are used to calculate the natural frequencies of FD-3 damper and the calculation results are compared and analyzed to prove the correctness of each model and the rationality of simplified treatment.Using the lumped mass model to study the calculation method of dampers power consumption,draw some power characteristic curves,and further study the influence of the structure parameters on power characteristics.Finally,the damping characteristics of dampers are studied by using the distributed mass model,a experimental method of identifying the system damping ratio is derived.Then the amplitude-frequency characteristic curve of FD-3 damper is drawn.The relationship between damping coefficient and excitatio n frequency is further studied and a experimental method of drawing the damping characteristic curve is introduced.