Characteristics of wind load on high-voltage disconnect switch system in substation

Ensuring high-voltage disconnect switch system safety is essential for the stable operation of the power system. A method for wind force tests to determine the wind load characteristics of the whole and the segments of the disconnect switch system was developed. Through this method, the distributions of aerodynamic coefficients for both the whole structure and its segments were determined, along with the skewed wind load coefficient relative to wind direction. The two-parameter model for wind load was used to predict wind load distribution along the structure's height. The study also considered the effect of different operating states of the disconnect switch system, namely, the switching-off and switching-on states, on wind force coefficients. Comparisons and analyses were performed to examine how these states influence the mean, fluctuating, and peak wind force coefficients, as well as the skewed wind load coefficient of the structure. The results indicate that the calculations of the two-parameter model are in good agreement with the measurements from the segment models. The most critical wind directions for the drag and skewed wind load coefficients for each segment of the structure were found to be 60° and 120°, respectively. Additionally, the mean wind load on the switch and insulator segments was higher than that on the steel columns. The switching-on state was identified as more detrimental to mean and fluctuating wind loads, with a pronounced effect on crosswind and torsional wind loads, especially on the torsional response of the structure.