Overview
Long Span Overhead Ground Wire is a critical component in high-voltage power transmission systems, installed above phase conductors to provide lightning protection. These wires are designed to withstand significant mechanical stresses while maintaining electrical performance over extended distances between transmission towers. Unlike standard ground wires, long span versions feature enhanced tensile strength and sag characteristics to accommodate spans up to several kilometers. They form part of the transmission line's overall protection system, significantly reducing outage risks from lightning strikes.
Structure and Working Principle
The wire typically consists of a high-strength steel core for mechanical support, often coated with zinc or aluminum for corrosion protection. Some designs use aluminum-clad steel wires or composite materials combining conductivity with mechanical resilience. During operation, the ground wire intercepts lightning strikes before they reach the live conductors below. The electrical energy is then safely conducted to ground through the transmission towers. This protection mechanism prevents dangerous voltage surges that could damage transformers and other equipment in the power system.
Key Features
Modern long span ground wires offer superior mechanical properties including high tensile strength (typically 50-70 kN) and excellent resistance to vibration fatigue. Their design minimizes sag over long distances while maintaining sufficient clearance from phase conductors. Electrical characteristics include low resistance (usually <1 Ω/km) and good conductivity for effective lightning current dissipation. Advanced versions may incorporate optical fibers for communication purposes, creating composite OPGW (Optical Ground Wire) solutions that serve dual purposes.
Application Areas
These specialized ground wires are primarily used in extra-high voltage (EHV) transmission lines crossing rivers, valleys, or other geographical obstacles requiring long spans. They're particularly valuable in mountainous terrain or coastal areas with high lightning activity. Major applications include inter-regional power grids, offshore wind farm connections, and critical infrastructure projects where reliability is paramount. Their use has expanded with growing renewable energy integration requiring long-distance power transmission.
Maintenance and Precautions
Regular inspection programs should include visual checks for corrosion, especially at suspension points, and assessment of any mechanical damage from environmental factors. Thermal imaging during operation can identify hot spots indicating potential issues. Installation requires careful tension control to avoid overstressing while maintaining proper clearance. In corrosive environments, selecting materials with enhanced protective coatings or considering higher-grade alloys becomes essential for long-term performance.
B2B Procurement Guide
When procuring long span overhead ground wire, buyers should specify the exact mechanical and electrical requirements including minimum breaking strength, DC resistance, and diameter. Environmental conditions (temperature range, pollution levels) significantly impact material selection. Quality certifications such as IEC 61089 or ASTM B498 are important indicators of manufacturing standards. Lead times can be significant for custom specifications, so project planning should account for this. Consider total lifecycle costs rather than just initial purchase price when evaluating options.
Related Manufacturers
- 主营：OPGW光缆、通信光缆、OPGW电力光缆
- 主营：风电光缆、管道光缆、导线金具、复合地线、复合架空地线、钢芯铝绞线、钢芯耐热铝合金绞线、扩径导线、铝包殷钢芯耐热导线、绝缘子、复合绝缘子、瓷绝缘子、玻璃绝缘子、光缆金具、避雷器、隔离开关熔断器
- 主营：绝缘线、管道光缆、铝包钢绞线、架空线、架空光缆、耐热铝合金绞线、铝包钢芯铝绞线
- 主营：钢芯铝绞线、铝包钢芯铝绞线、耐热钢芯铝铝合金绞线、架空绝缘导线、轻型钢芯铝绞线、防腐钢芯铝绞线、铝包钢芯耐热导线、OPGW光缆、ADSS光缆、钢绞线、扩径导线、铝包钢绞线、导线金具、光缆金具、管道光缆、绝缘子、避雷器、熔断器、铝包殷钢芯耐热导线、鼓励开关、OPPC光缆、镀铝锌钢绞线、电力铁附件
- 主营：钢芯铝绞线、铝包钢芯铝绞线、铝包钢芯耐热铝合金绞线、大截面钢芯铝绞线、1千伏架空线、10千伏架空绝缘导线、35千伏架空绝缘导线、高导电率钢芯铝绞线、铝绞线、扩经导线、碳纤维复合芯导线、铝包殷钢超耐热铝合金导线、铝包钢绞线、OPGW光缆、OPPC电力相线光缆、ADSS光缆、玻璃绝缘子
- 主营：钢芯铝绞线、电力金具、电力光缆、架空绝缘导线、OPGW光缆
- 主营：电力光缆、钢芯铝绞线、电力金具、架空地线、架空光缆、架空导线、架空线电缆、光缆金具、电站金具、铝合金导线、耐热导线、管型母线、铝包殷钢导线、增容导线
- 主营：钢芯铝绞线、铝包钢芯铝绞线、镀锌钢绞线、绝缘架空线、铝包钢绞线、OPGW光缆、全系列金具、耐热铝合金导线、矿用电缆、计算机电缆、橡套电缆、控制电缆、特种电缆
- 主营：铝包钢芯铝绞线、钢芯铝绞线、铝包钢绞线、架空绝缘导线、35kv架空绝缘线、架空绝缘线、钢芯铝合金绞线、OPGW光缆、扩经导线、OPPC光缆、钢芯耐热铝合金绞线、铝包钢芯耐热铝合金绞线、铝合金芯绞线、特轻型导线、镀锌钢绞线、光伏电缆、ADSS光缆
- 主营：电力光缆、铝合金绞线、钢芯铝绞线、架空绝缘导线、金具
- 主营：导线金具、钢芯铝绞线、铝包钢芯铝绞线、架空绝缘导线、OPGW光缆、ADSS光缆、特轻型钢芯铝绞线、铝包钢芯耐热铝合金绞、耐热铝合金导线、钢绞线、铝包钢绞线、扩径导线、光缆金具、耐热钢芯铝绞线、耐张线夹、绝缘子、悬垂线夹
- 主营：架空导线、钢芯铝绞线
- 主营：梯式桥架、防火桥架、电缆桥架、大跨距桥架、热浸锌桥架