Multi-factor Reliability Evaluation and Analysis Method of HVDC Transmission Line Considering the Influence of External Environment

As UHV transmission lines are built, their stability demands are becoming more and more stringent, and the external environment is becoming more and more complex, therefore, a reliability assessment of HVDC transmission lines is required. At present, domestic and foreign scholars are lack of systematic research on electrical reliability evaluation of transmission lines, so this paper puts forward a multi-factor reliability evaluation and analysis method of HVDC transmission lines considering the influence of external environmental factors. Firstly, the factors affecting the electrical reliability of transmission lines are analyzed, moreover, in accordance with the properties of transmission lines, the minimum cut set method or based on load-strength distribution interference model is recommended to study the reliability. Secondly, a refine calculation method of flashover probability in the case of transmission line pollution, icing, windage yaw, lightning strike, mountain fire and landslide is established. Finally, through the calculation of an engineering example, the reliability of HVDC transmission lines is evaluated, and the results show that the reliability of HV transmission lines is at a high level.