The Research And Development Of The Device Of Abanding Wires To Protect Electric Poles In Distribution Network Lines

The collapse and broken of the poles were the most serious accidents in the whole distribution network system and it would cause huge economic losses.China Southern Power Grid Co.,LTD had attached great importance to this situation and came out with the concept that abandoning wires to protect electric poles,which mean to abandon the wires from the poles and release the wire tension,so the poles would be protected.Based on the concept above,the paper developed a device of abanding wires to protect electric poles funded by practical projects and made some research of the design,analysis,optimizeand and experimental test about the device,which provided the theory and basis to further develop.Finally,a device that had able to be used in the actual distribution network system had been produced.First of all,it set up the mathematical model of the pole stress according to the actual working condition of distribution network lines and got the formula of the pole stress,which could be used to discuss the influence between the stress of pole and the wind load,then it chose typical wires to calculate the bending moment of the poles,which provided some basis to develop the device of abandoning wires to protect electric poles.Secondly,it designed and studied the overall structure of the device.By compareing with the advantages and disadvantages of the existing devices,it came up with a device of abandoning wires to protect electric poles with overload protection function and introduces the action principle of the device concretely.Thirdly,it studied the key components “annular ring” of the device,and did some theoretical analysis of its deformation under outside load by the method of Castigliano’s second theorem and Dummy-load method.Based on ANSYS-workbench,it made finite element analysis and optimization design of the annular ring.Finally,the feasibility of the action about the annular ring going across the step of the cutting edge shaft had been verified by the axial tension experiment.Finally,it simulated this process by using transient dynamic FEA method.Fourthly,it made the 3D design of the device and worked out with a series of prototype devices.Simulated the liquidity of internal gas inside the cavity based on Fluent and optimized the size of flow aperture.Designed the experimental frame and did the drop experiment of the off-line action of the prototype.The result of the experiment explained that reliability and stability of the off-line action of the devices.Finally,Modal analysis was carried out on the whole device to obtain the first six order natural frequency.The wind load time history had been got by calculating the time history of turbulent wind speed based on AR method.Fatigue analysis of the annular ring was carried out based on the nCode Designlife and the weaking sections were determined.Wind tunnel test was established to prove the reliability of the off-line action of the device and that it complied with the design value theory.Selected the specific types of the devices and worked them out for the protection in destribution network lines.