Research On LGJ-400/50 ACSR Surface Erosion Characteristics In Wind Sand Environment

There are many factors influencing the corona characteristics of transmission line.Among them, the surface state of transmission line is an important factor. Therefore, there are important guiding significance to the experimental investigation on LGJ-400/50 ACSR surface erosion characteristics in wind sand environment.In this paper, using the typical line on 750 kV Transmission Line ProjectLGJ-400/50 ACSR cable as the experimental material, using concentration, wind speed and other parameters measuring equipment, cooperated with light-section microscope Matlab image processing programs, this experiment simulated erosion effects of wire surface state in various particle sizes, wind environmental. Before the experiment, Using Fluent software, the flow field of wind tunnel experimental section and pressure contour around the cable was simulated in four different angles.The results show that: the maximμm pressure around the cable was appeared in the windward side, the maximμm negative pressure was appeared in the region which the angle were nearly 45-degree from leeward side; In the leeward side it will form two symmetrical vortex. Then, through the physical simulation experiment,The results show that: under the condition of 30°attack angle, the wire surface erosion is more serious; trends of the surface roughness curve are basically the same. It can be divided into two stages: the fast rising stage and stable stage. After erosion surface roughness are mostly varied in 6 ~ 12μm.By using LS-DYNA software, the impact process of single particle on cable surface was simulated under the condition of different angles and particle size. The results show that: maximμm impact force of 0.25 mm sand particle size was 0.372MPa; maximμm impact force of 0.5mm was 0.372MPa; Surface stress under 30 °attack angle is smaller but the stress was tangential direction, the impact of stress area is larger than the former method.With the help of scanning electron microscope, surface morphology after the erosion can be observed. When the attack angle is 90° wire surface appears irregular erosion pit, while in the cases of the other three angles, surface appears dunes waves along with the wind direction. Also, this paper made the elaboration of erosion mechanism under the four different attack angles. Analysis on sample surface energy spectra show that: the content of Si and O is increased and surface formed hard protection film which increases the ability to resist erosion. Finally, this article analyzed the erosion mechanism under different attack angles.