Wind load characteristics of 1 000 kV UHV substation frame

Abstract:

With time series data of base bending moments and forces simultaneously measured by high frequency force balance (HFFB) wind tunnel test of 1 000 kV ultra-high voltage (UHV) substation frame in uniform flow, terrain A, and terrain B, the power spectrum density (PSD) and statistical characteristics such as mean value, root mean square (RMS), kurtosis, and skewness of aerodynamic coefficients of the whole substation frame and segment models were compared and analyzed. The influence rules of wind direction, terrain type, and other factors on the wind load characteristics were investigated, and the proportional relationship of aerodynamic force coefficient characteristic between the overall model and segment models of the substation structure under different flow fields was discussed. Results show that taking segment model A as an example, the ratio of mean values of C_x in uniform flow field, terrain A, and terrain B landforms at 0° wind direction was 1∶[KG-2mm]1.58∶[KG-2mm]1.57 and that of its RMS values was 1∶[KG-2mm]1.60∶[KG-2mm]1.59. Correspondingly, the ratios of mean values and RMS values of C_y were 1∶[KG-2mm]7.0∶[KG-2mm]7.57 and 1∶[KG-2mm]1.53∶[KG-2mm]1.30, respectively. Contrastive analysis of the overall model and various segment models demonstrates that in the uniform flow field at 90° wind direction, the ratios of mean values and RMS values of C_x for the overall model and four segment models were 1∶[KG-2mm]0.02∶[KG-2mm]0.26∶[KG-2mm]0.22∶[KG-2mm]0.38 and 1∶[KG-2mm]0.06∶[KG-2mm]0.37∶[KG-2mm]0.32∶[KG-2mm]0.41, respectively. While the ratios of mean values and RMS values of C_y were 1∶[KG-2mm]0.46∶[KG-2mm]0.57∶[KG-2mm]0.43∶[KG-2mm]0.69 and 1∶[KG-2mm]0.47∶[KG-2mm]0.58∶[KG-2mm]0.44∶[KG-2mm]0.70, respectively. The most unfavorable wind direction and design wind load of 1 000 kV UHV substation frame were determined by comprehensive comparative analysis of time and frequency domains, which provides reference for engineering design.