Skewed Wind Load Design Methodology for Tower Head and Full Frame of 1000 kV UHV Substation Framework

This study presents a comprehensive investigation of the design wind loads for 1 000 kV UHV substation frame and tower head, which is critically important for the structural safety design of wind loads on lattice structures for substation and transmission. Wind tunnel tests on full frame and head tower models of a 1 000 kV UHV substation frame under uniform flow, terrain A and terrain B are carried out. The drag coefficients, skewed wind load factors, and the wind load distribution factors in the transversal and longitudinal direction of the substation frame and tower head are calculated and compared with the relevant specifications. The influence of wind fields and wind incidence angles on the wind load characteristics is investigated. The fitting functions for the drag coefficients, skewed wind load factors and wind load distribution factors of the full tower and head tower are determined by nonlinear fitting analysis. The calculation methods of transversal and longitudinal wind loads for the 1 000 kV UHV substation frame under skewed wind loading are proposed.