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In order to simulate the non-stationary typhoon wind field of overhead transmission lines, a simulation method for the non-stationary typhoon wind field of overhead transmission lines was proposed, taking into account the turbulence intensity and gust factor characteristics and their effects of the non-stationary pulsating wind field. Firstly, the Spline interpolation method was used to generate time-varying average wind speed, and the harmonic synthesis method of updating time-varying average wind speed was used to simulate fluctuating wind speed. Then, based on the three-dimensional wind spectrum power density function, the time-varying power spectrum of the typhoon wind field was constructed, taking into account the spatial correlation of the wind field, and the modulation evolution power spectrum was obtained, which is compared with the simulated typhoon power spectrum. Finally, taking the coastal 500 kV overhead transmission line as an example, the rationality of the typhoon simulation method was verified. The research results indicate that as the basic time interval increases, the proportion of non-stationary factors in typhoons increases. The non-stationary typhoon simulation method proposed can achieve the simulation of non-stationary typhoon wind fields on transmission lines. [ABSTRACT FROM AUTHOR]

In order to master the dynamic response characteristics of transmission tower in mountainous area, taking the T-shaped transmission tower of 800kV UHV transmission line in mountainous area as the object, the finite element model of transmission tower rolling stone impact is established by using nonlinear explicit dynamic analysis software. The rod deformation, stress and time history change in the impact area of transmission tower are studied. The effects of rolling stone impact position, velocity, angle and mass on the impact response of transmission tower are analysed. The calculation formula of peak impact force of rolling stone of transmission tower is given and compared. The results show that the rolling stone impact force of transmission tower presents a triangular pulse shape, with short duration and large impact force; The deformation of auxiliary materials in the impact area of transmission tower is large, and the stress of its rod is the most unfavourable. During the impact, the stress level of the tower rod reaches the peak value instantaneously, then oscillates and decays rapidly, and gradually tends to be stable; After the impact of rolling stone, the tower pole will undergo plastic deformation, and the residual axial stress level of the tower pole is greater than the residual shear stress; When the impact position of the rolling stone is 1/6 to 1/8 tower height, the peak impact force of the rolling stone and the residual axial stress of the rod are relatively large. When the impact angle is 0 °, the impact response of transmission tower is the most severe. The impact velocity and rolling stone diameter have great influence on the impact response of transmission tower; The peak value fitting formula of impact force can be used to estimate the impact force of rolling stone of transmission tower. [ABSTRACT FROM AUTHOR]