基于空气动力学分析的绝缘空中输电线路的冲行为
Hucheng Liang1, Zekai Zhang1, Xiaoxiao Kong2
1Key Laboratory of Smart Grid of Ministry of Education, School of Electrical and Information Engineering, Tianjin University, Tianjin, China.
Scientific reports
|January 21, 2025
概括
在极端天气条件下,冰的输电线路会出现严重的冲,导致电网不稳定. 半月形的冰积累导致比圆冰更激烈的飞行 (高达1.7米),影响电网安全.
科学领域:
- 电气工程 电气工程
- 空气动力学 航空动力学
- 机械工程 机械工程
背景情况:
- 冰的输电线路的冲动对电网稳定性和结构完整性构成重大威胁.
- 极端天气条件加剧了与空中电力线路积冰相关的风险.
研究的目的:
- 研究各种因素对冰冷输电线路的飞行行为和空气动力学特征的影响.
- 分析冰的形状 (圆形与新月形) 和风力条件对直线的影响.
- 为空中绝缘输电线路的故障分析和马预测提供理论参考.
主要方法:
- 使用有限元法开发10kV绝缘空中输电线的模拟模型.
- 在不同风速和攻击角度下,分析飞行行为和空气动力学特征.
- 对圆形和半月形冰层的冲动动态进行比较.
主要成果:
- 冰线在风速为7-15m/s和风的攻击角度约为50°时观察到最差的空气动力学稳定性.
- 对于冰线,随着风速的增加,最大冲位移的非线性增加.
- 与圆形的冰线相比,半月形的冰线表现出更强烈的冲 (最大位移1.7米).
- 转折点的风速确定为圆形的5米/秒,半月形冰的9米/秒.
结论:
- 冰的形状显著影响了输电线路的严重程度.
- 半月形的冰积累带来了更大的严重冲刺和潜在损伤的风险.
- 研究结果为改善电网对天气引起的故障的安全性和可靠性提供了关键的见解.
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