Common Fault Causes and Modeling Methods for HVDC Transmission Lines

High-voltage direct current (HVDC) transmission lines face multiple fault causes due to their long transmission distances and complex environments, including lightning strikes, bird-related damage, floating objects, ice coating, wildfires, vegetation, pollution flashover, and human factors. Nevertheless, current research exhibits limitations in fault type refinement and data sample quality, and the varying fault responses across different HVDC transmission systems present challenges to model generalizability. This paper conducts an in-depth investigation of common fault-inducing factors in HVDC transmission lines and their modeling methods. First, it analyzes the fault mechanisms and characteristic features of various causative factors, clarifying their corresponding fault types. Subsequently, the transmission tower modeling methodology is elaborated. Finally, focusing on four major fault categories - grounding faults, line break faults, positive-negative poles short-circuit faults, and lightning strike faults - corresponding modeling approaches are proposed based on specific fault scenarios. This research provides theoretical foundations for fault cause identification in HVDC transmission lines.