Radio Interference Prediction Method for EHV AC Transmission Lines at High Altitudes Based on Long-Term Observations

Abstract

Radio interference (RI) is a critical factor in the design of extra-high voltage (EHV) transmission lines at high altitudes. To address the insufficient field data of RI on high-altitude transmission lines, the lack of adequate validation for existing RI prediction methods, and the difficulty in assessing RI levels under various meteorological parameters, this study investigated prediction methods for RI in high-altitude AC transmission lines based on long-term observations. First, the altitude correction factors for RI were investigated by comparing long-term observational data from different altitudes and results of movable corona cage tests. Second, a more accurate RI prediction method for high-altitude transmission lines was proposed by comparing the long-term measured data from four high-altitude observation stations with the predicted values derived from various formulae. Finally, correlation and multiple regression analyses were employed to develop RI prediction models considering the effects of different meteorological parameters under both rainy and fair weather conditions. The accuracy of these models was validated using actual measurement data. The findings provide important references for the prediction and evaluation of RI from EHV AC transmission lines at high altitudes.