冰风耦合环境下连接金具数值仿真分析

覆冰导线受风载作用产生的动张力可能会导致金具失效断裂，严重影响电网运行安全。为评估冰风载荷对连接金具的耦合影响，数值模拟得到随机风作用下不同覆冰形式导线关键点处动张力和位移，采用有限元软件ANSYS建立连接金具模型，对极端环境下整体连接金具应力场进行数值仿真，找出金具薄弱位置，并对危险部件U形挂环进行动力响应分析，分别探讨覆冰形式、张力变化、受力形式对U形环应力分布影响。结果表明：连接金具在极大冰风载荷下，U形挂环最容易出现失效，最大应力值为509.0 MPa,其次是联板孔洞处与挂板弯折处。对U形环的动力响应分析中，导线均匀覆冰时，覆冰15 mm时U形环有最大应力值为996.4 MPa,导线线性覆冰时，中央重覆冰下U形环发生屈服面积大于两侧重覆冰；在动张力作用下，当U形环间存在转动关系时要比纯张力作用下对U形环损害更加严重。

Numerical simulation analysis of connecting fittings under the coupling environment of ice and wind

The dynamic tension generated by the wind load of the icing conductor can easily cause fittings to fail and break, thereby affecting the safety of power grid operation. In order to evaluate the coupling influence of ice load and wind load on the collecting fittings. The numerical simulation obtained the dynamic tension and displacement at the key points of the conductor under different icing forms. Establish the fine metal model of fittings by software ANSYS. The stress field of Integral connection fittings under extreme environment is simulated to find out the weak position. The dynamic response analysis of the U-ring of dangerous parts was carried out, and the influence of icing form, dynamic tension and force form on the stress distribution of the U-ring was discussed. The results show that U-shackles is the most prone to failure in integral connection fittings under extreme ice wind load, and the maximum stress value is 509.02MPa, followed by the hole of connecting plate and the bend of the hanging plate. In the dynamic response analysis of the U-ring, the maximum stress value of the U-ring is 996.37MPa when the ice is uniformly covered by 15 mm. In the case of linear icing, the area beyond the yield limit of thick ice in the middle of the conductor is larger than that of thick ice on both sides of the conductor. Under the action of dynamic tension, when there is a rotational relationship between U-shackles, the damage to U-shackles is more serious than that under the action of pure tension.