Abstract:

In the design of overhead transmission lines, design changes frequently occur during inter-conductor clearance verification to satisfy stringent mechanical and insulation safety constraints. To address the low efficiency of variant design caused by switching among multiple software modules, repeated procedures, and excessive iterations in traditional methods, a fast variant design-supporting methodology for inter-conductor clearance verification was established. Firstly, based on the Top Basic Skeleton (TBS) modeling theory, a top-down design flow was proposed. In the proposed design flow, the tower design control information and top-level design requirements were transmitted to the conductor configuration parameters, enabling the clearance-verification process to respond rapidly to common design changes. Subsequently, in accordance with the model-granularity requirements of the design flow, a lightweight transmission-line skeleton model comprising conductors, towers, and their assembly relationships was developed. Specifically, a lightweight tower-shape skeleton was constructed by referencing general model definitions from industrial standards, enabling rapid creation and modification of towers. Meanwhile, a tower-positioning skeleton was built following the TBS lateral layout modeling approach, allowing efficient and accurate transfer of design changes. Additionally, a conductor skeleton model integrating both geometric and design information was established to facilitate data sharing for rapid mechanical calculation of wires. Furthermore, an assembly model incorporating the connections between towers and conductors was constructed to ensure data consistency in variant design and adaptability to complex line configurations. Finally, a corresponding prototype inter-conductor clearance verification system was developed based on the Qt platform, and various typical and special transmission line projects were used as case studies to demonstrate the application of variant design requirements. The results demonstrated that the proposed method effectively supported the four major types of rapid variant-designs: adjusting tower position, tower-top geometry, phase sequence arrangement, and custom operating conditions, while exhibiting good scalability for complex tension-section-level overhead transmission-line projects. Consequently, this research provided an efficient and flexible technical approach for increasing the efficiency of the insulation coordination design.

Key words: overhead transmission lines, inter-conductor clearance verification, variant design, top-down, skeleton model