How can super-large bending moment poles with low deflection reduce the risk of conductor swing during long-term transmission line operation?
Publish Time: 2025-10-02
During the long-term operation of high-voltage transmission lines, external environmental factors such as strong winds, icing, and earthquakes can easily cause violent conductor swing. In severe cases, this can lead to major accidents such as phase flashover, power outages, and even tower collapse. While traditional angle iron towers and steel tubular poles offer high load-bearing capacity, they can still experience structural deformation and excessive deflection in areas with large spans, heavy loads, or strong winds, further exacerbating conductor dynamic movement. In recent years, a new type of "super-large bending moment pole" has emerged as a preferred alternative to traditional towers due to its high elastic modulus, low deflection, and superior mechanical properties. It demonstrates significant advantages in reducing the risk of conductor swing.1. Low Deflection: The Mechanical Basis for Suppressing Conductor SwingOne of the fundamental causes of conductor swing is the elastic deformation of the tower under lateral loads such as wind and icing. Significant displacement of the tower top directly causes additional swing in the insulator strings and conductors, creating a chain reaction of "pole-line motion." Super-large bending moment poles utilize high-strength concrete or prestressed reinforced concrete structures. Through scientific reinforcement design, their bending stiffness and overall stability are significantly improved. Their elastic modulus is significantly higher than that of ordinary steel, meaning they experience less deformation under the same load. Field measurements show that under equivalent wind pressure, the top horizontal displacement of super-large bending moment poles can be reduced by over 30% compared to traditional angle iron towers. This effectively reduces the initial disturbance of the conductors caused by pole sway, curbing the amplification effect of sway at the source.2. High-Bearing Capacity and High-Bending-Moment Design: Coping with Extreme LoadsThe super-large bending moment pole's name stems from its exceptional bending resistance. Through optimized cross-sectional design and increased longitudinal reinforcement ratio, its ultimate bending moment bearing capacity is comparable to, or even higher than, that of angle iron towers or steel tubular poles of the same specifications. This high bearing capacity ensures structural stability even in extreme weather conditions such as strong winds and icing, preventing plastic deformation or instability caused by overload. Especially on wide-span lines or at corners, conductor tension is concentrated, placing extremely high demands on the tower's bending moment. Super-large bending moment poles can reliably withstand these concentrated loads, preventing excessive local stress from causing pole tilt or foundation loosening, thereby ensuring the stability of the conductor suspension point.3. Strong structural integrity reduces vibration transmissionCompared to the truss-like structure of angle towers, super-large bending moment poles are monolithic solid or hollow poles, offering superior structural continuity and fewer joints. This prevents micro-vibrations caused by loose bolts and fatigued connections. While subtle, these micro-vibrations can accumulate over time and be transmitted to the conductors through insulator strings, inducing breeze vibration or flutter. The integral rigid structure of super-large bending moment poles effectively blocks these vibration transmission paths, improving the system's dynamic stability. Furthermore, their base provides a more secure connection to the foundation, providing strong resistance to overturning and further enhancing the tower's overall anti-disturbance performance.4. Dimensional stability during long-term operationTransmission lines often operate for decades, and material aging and creep can affect structural performance. Super-large bending moment poles are constructed of high-performance concrete and corrosion-resistant steel, offering exceptional durability and resistance to environmental corrosion. Their dimensional stability far surpasses that of steel, preventing significant creep deformation due to long-term loads. This means that over decades of service, the pole's geometry and mechanical parameters remain highly consistent, ensuring that the conductor's suspension height and tension distribution remain within the designed range. This prevents conductor slack or tension imbalance caused by tower settlement or deformation, fundamentally reducing the risk of sway during long-term operation.5. Strong Adaptability, Improving System ReliabilitySuper-large bending moment poles offer flexible load-bearing capacity improvements through adjustable reinforcement schemes while maintaining a fixed pole diameter. They are suitable for transmission lines operating at varying voltage levels and terrain conditions. Their compact structure also saves space in transmission corridors, making them particularly suitable for urban fringe areas, forested areas, or areas with complex terrain. In these locations, traditional angle iron towers can exacerbate conductor sway due to wind channeling or terrain uplift. Super-large bending moment poles, with their low deflection and high stability, effectively handle complex airflow environments, improving the safety margin of the entire transmission system.The super-large bending moment pole, with its low deflection, significantly reduces the risk of conductor sway during long-term transmission line operation through its high elastic modulus, excellent flexural stiffness, and overall structural stability. It not only boasts a load-bearing capacity comparable to angle iron towers and steel poles, but also exhibits unique advantages in suppressing deformation, reducing vibration transmission, and ensuring long-term dimensional stability. As power grid safety and reliability requirements continue to increase, the super-large bending moment pole will become a crucial support structure for building a robust smart grid, providing a solid foundation for the stable operation of the power system.
