多参数影响下输电线链式脱冰实验研究

Experimental research on zipped ice-shedding of transmission line under the influence of multiple parameters

输电线路脱冰振动产生的动态张力严重时将会导致线路断裂、倒塌等事故。文章以某工程为原型,基于动力相似理论,设计出1∶30的单跨覆冰输电线的缩尺模型,采用电磁铁控制集中重物的释放来模拟覆冰输电线中冰荷载的脱落,开展链式脱冰和瞬时脱冰实验研究。研究了脱冰速度、脱冰方向,以及高差和防振锤单跨输电线脱冰振动响应的影响。结果表明:链式脱冰比瞬时脱冰跳跃高度低;无论是链式还是瞬时脱冰,脱冰跳跃最大高度随脱冰速度减小而减小,最终趋于瞬时脱冰的50%;在有减振装置防振锤情况下,链式脱冰减振效果更加明显;跳跃最大高度随高差倾角的增大而急剧增大,从中间到两边的脱冰方式最不利。

The dynamic tension caused by the ice-shedding of the transmission lines will cause the line fracture and collapse.Taking a project as the prototype,this paper designed a test model of an iced conductor with scale ratio of 1∶30 on the basis of dynamic similarity theory to simulate the ice shedding of transmission lines,using electromagnet to control the shedding of concentrated weight in the cases of zippered and simultaneous ice-shedding.The influence of deicing velocity,deicing direction,elevation difference and vibration-proof hammer on the vibration response of transmission lines ice-shedding were studied.The results show that the displacement of zippered ice-shedding is lower than that of simultaneous ice-shedding.Whether it is zippered ice-shedding or simultaneous ice-shedding,the maximum jump height of zippared ice-shedding decreases with the decrease of the deicing velocity,and eventually reaches up to 50%of simultaneous ice-shedding.With the vibration-proof hammer,the jump height of zippered ice-shedding is more obvious.The maximum jump height of the mid span increases sharply with the increase of the elevation difference angle,and the deicing mode from the middle to both sides is the most unfavorable.